1270

BID: 580_WB4D    
Subject: ittermittent MFJ crashes...

Those of you that are using the older MFJ 1270 with the mini phone connector
for the DC input would be wise to replace this connector with a "coaxial" type.
For th  past 2 weeks, I've been fighting an intermittent BLOCK TIMEOUT error
whi
ch
was caused by this cheap connccto.. It wasn't bad enough to completely reset
the TNC - but did confuse hostmode protocol. Physically moving the TNC didnt
reveal this problem. The mini phone connector was a poor choice for a DC 
connector and should be replaced even if you don't show any problems --now...
73 de Les
         RELAYED  BY...N0KGX...GENE
         1270B

    From : W3CSG @ WB4D.VA.USA.NA
      To : MFJMOD @ ALLUS
    Date : 900724/1806
   MsgID : BF 2079@WB4D, 605@KJ6YT $2079_WB4D
 Subject : More TX audio from MFJ1270B/1274

Need more TX audio to drive a commerical radio or inject past the limiter?
The following mod will increase the stock output from a MFJ1270B or 1274
TNC from about 200mv with tone twist to about 500mv with no tone twist.

Change R56 from 7.5K to 4.7K
Jumper out cap C71
Remove cap C73
Install 1mfd caps at C34 and C35  (caps shown on board but missing)

The above changes will make the TNC TX audio the same as the older
MFJ1270 and TAPR TNC2 units.
I am presently using this mod in order to drive Motorola and GE radios
in my node stack.
73 Royce W3CSG @ WB4D.VA.USA.NA
1274


    From : W3CSG @ WB4D.VA.USA.NA
      To : MFJMOD @ ALLUS
    Date : 900724/1806
   MsgID : BF 2079@WB4D, 605@KJ6YT $2079_WB4D
 Subject : More TX audio from MFJ1270B/1274


Need more TX audio to drive a commerical radio or inject past the limiter?
The following mod will increase the stock output from a MFJ1270B or 1274
TNC from about 200mv with tone twist to about 500mv with no tone twist.

Change R56 from 7.5K to 4.7K
Jumper out cap C71
Remove cap C73
Install 1mfd caps at C34 and C35  (caps shown on board but missing)

The above changes will make the TNC TX audio the same as the older
MFJ1270 and TAPR TNC2 units.
I am presently using this mod in order to drive Motorola and GE radios
in my node stack.
73 Royce W3CSG @ WB4D.VA.USA.NA
1278

MJF IS PROVIDING A NICE LITTLE SERVICE TO THERE CUSTOMERS THEY ARE GIVING AWAY
FREE ROM UPGRADES FOR THE 1278 MULTI-MODE DATA CONTROLER. HERE'S HOW IT WORKS.
IF YOUR 1278 IS BETWEEN SERIAL NO. 0301002 - 03010508 YOU MUST SEND THE UNIT TO
MJF TO HAVE IT IN
STALLED. IF YOUR UNIT IS AFTER SERIAL NO 03010508 THEN THEY WILL SEND YOU THE
NEW ROM. HERE'S THE CATCH (ISN'T THERE ALWAYS A CATCH?) YOU HAVE TO SEND THEM
BACK YOUR OLD ROM (NOT TOO BAD OF A DEAL) TO GET THIS CALL MJF AT
1-800-647-1800 AND TELL THEM YOU 
WANT TO ORDER A MFJ-48 ROM UPGRADE FOR THE 1278 (HAVE YOUR SERIAL NUMBER HANDY
THERE GONNA WANT IT) NOW YOU WILL BE CHARGED FOR IT BUT WHEN YOU SEND THEM BACK
YOUR OLD ROM THEY WILL REEMBURSE YOU. SO ALL IN ALL IT'S A PRETTY GOOD DEAL.
ONE OF THERE TECHS 
TOLD ME ABOUT THIS AND I THOUGHT IT WAS AN OFFER TOO GOOD TO BE TRUE. THE NEW
ROM HAS A MAILBOX (THE BIGGEST FEATURE) & SOME OTHER IMPROVEMENTS AS WELL.
ENJOY THE UPGRADE 73'S ....de Harry/KB6WVJ
2016A
SCAN DEFEAT DURING XMIT FOR KDK 2016A

Anyone with a KDK-2016A has either fixed this or learned to live with
it, but here goes anyway:

The 4-channel memory scan on the KDK 2016A is designed to be active
whenever a) the memory channel switch is in the "scan" position and b)
when the RCV LED on the front panel is not lit.  To keep the receiver
tuned to an active channel once it's hit, the same signal that drives
the RCV light is picked off on its path via a white/yellow wire from
P24 of the main board to the display unit; the signal also goes to P9
on the synthesizer unit, where it is RC shaped and fed to the base of
Q12, whose collector circuit stops the scan when the LED comes on.

The problem is this: if you decide to talk to someone you hear on an
active scanned channel -- and forget to first move the switch from
the scan position -- as soon as you key the mike, the RCV LED goes out
(doesn't that make sense?) and bingo! scanning begins again.  The
effect of this is to spread yourself around a bit -- 1/3 sec on one
channel, 1/3 on another.... Kind of a primitive "spread-spectrum" but
not guaranteed to win friends on the other repeaters you may have in
memory.  If you notice the frequencies flashing by on the display, you
can catch this in time to save yourself some embarrassment, but there
is another workaround.  I installed this mod about ten years ago, and
it's still doing fine.
CONTINUED IN FILE 2016A.1
2510

Is your 2510 slow on agc??? does it take 3 frames at 1200b for the
rx to come up to sensitivity?? do you want to make the rit a rtit (rxtxit)
then maybe these mods will help you, they also may apply for the newer 
versions of this radio, you who have the 2600 may be able to use them.
mod 1.
 speed up agc, this is easy, just pull out the transistor q111 and you have
fast agc, if you need to select slow agc then put a switch from the collector
to emitter and pull the collector pad to ground for slow agc 
mod 2.
 make the tx and rx both responde to the rit control and reduce the amount
of frequency change for the control.
this one requires that you locate the rit control and remove the following:
r 802  a 1k resistor in series with the rit pot
the rx 8v line that goes to high side of pot, remove and put aside, you
will need it for power to nb switch and rf gain control.
now remove the subassembly b801 pb-120 and remove r802. cut pc land between
high side of vr802 and r 801 you will now solder the rx 8v line to the
freed side of r 801.
CONTINUED IN FILE 2510.1
ALR206T

PK-232 TO ALINCO ALR206T MIKE CIRCUIT

                      /-<- .1UF CAPACITOR 
(AUDIO)              WHITE WIRE ----------][--------                           

   ---- CONNECT TO PIN 1 ON  
RED WIRE   -----/\/\/\/--------      ALR 206T
(P.T.T.)                                 \-<- 33K OHM RESISTOR
(GND)
BROWN AND SHIELD WIRE------CONNECT TO PIN 7 ON ALR 206T

WHITE WIRE = AFSK AUDIO OUT
RED WIRE =   PTT
BROWN WIRE = GROUND
SHEILD =     GROUND
CAPACITOR = .1 UF @ 25WVDC
RESISTOR =   33K OHM @ 1/8 WATT

A SIMILAR CIRCUIT MAY WORK FOR OTHERS THAT DO NOT HAVE A SEPARATE PTT LINE
                       RELAYED BY...N0KGX...GENE
ALR22T
    From : WA2ISE @ KD6TH.NJ.USA
      To : MODS @ ALLUS
    Date : 900609/0441
   MsgID : BF 28114@KD6TH, 673@KJ6YT $966_WA2ISE
 Subject : alr22t mod file

Date: 09 Jun 90 04:41:55 UTC (Sat)
From: wa2ise@kd6th.nj.usa (Bob)
Message-ID: <28114@KD6TH.NJ.USA>
Reply-To: wa2ise@wa2ise
To: mods@allbbs
Subject: alr22t mod file

Do not modify your radio unless you:
1) plan to drive a transverter
2) want to test a receiver (drive a dummy load and listen for leakage)
3) have the MARS or CAP permits.
You cannot use this radio on public service bands because it is NOT 
type accepted by the FCC.
>Don't transmit out of band!<
I haven't tried or verified this mod, proceed at your own risk.
WA2ISE
CONTINUED IN FILE ALR22T.2
From: ewb@raybed2.UUCP (EUGENE BALINSKI)
Newsgroups: rec.ham-radio
Subject: AOR-2515 receiver
Date-Received: 10 Feb 89 23:19:39 GMT
Organization: Raytheon Co., Bedford, Mass.

Here is a little more info on the AOR 2515. According to ACE/AOR there is a 
software package available to run the 2515 from an IBM-PC. It apparently
gives you full operation of the scanner as well as the ability to 
graph channel usage ! Scanner memory can be expanded by the computer.
It is unknown whether is will log "search and destroy" type scanning. 
Price will be about $40.00. Cable is included. 
     Also delivery on the 2515 is running at 4 to 6 weeks.
  
    73
    WA1UXA         RERUN...BY...N0KGX...GENE

trio-kenwood auto atu-940-440-at250 (part one)
the "memory" problem that g4xjp is experiencing with his atu's will become more
common as atu's will become more common as atu's get older.  in all cases, i
have traced the problem to one of two areas.  
1.  problem exists on only one band.  cure:  replace the band select relay.
2.  problem exists on all band.  cure:  replace the transmit/recieve relay.

a couple of additional tips:
1.  if you don't have a 150 ohm dummy load don't attempptj to align swr bridge.
2.  good grounding is extremely important.  all mounting screws should be well
snugged.  

by: don taylor   RELAYED BY...N0KGX...GENE


at-500 automatic antenna tuner modification
i have been using the icom at-500 automatic antenna tuner for six months, and
it is a great piece of gear.  however, there is a very minor modification i
performed to the tuner to better suit my needs.
the tuner automatiacally selects one of four antenna s0-239 connectors on the
back depending upon which band you are operating.  many of us utilize one feed
line for an 80 and 40 meter dipole or inverted vee.  the at-500 (and at-100)
has two seperate antenna terminals for these bands.  if you desire to use one
feed line for both of these lower band antennas, you either have to install a
coax switch and manually switch the tuner in line, or unscrew the pl-259
connector from one antenna terminal and install it on the other.  all of this
is inconvenient and defeats athe purpose of an automatic tuner.  the mod i
performed is extremely simple.  i moved the wire going to antenna terminal #3
and moved it to terminal #2.  this directs the 80 meter rf to the same terminal
as the rf for 40 meters and allows one to use the same antenna terminal for
both bands and one feed line.  to perform the change, remove the top cover of
the tuner, locate the two correct terminals using page 6 of the manula,
unsolder the one to be move, and s9lder it to the correct terminal.  the
terminals are easy to reach.   just be sure all connections are good.  

by ku5j.        RELAYED  BY  N0KGX...GENE


see files bc200xlt.1 -.5 for mod info on

cellular restoration
800 mhz mod
test mode
bc205xlt

see files bc205xlt.1 - .5 on mods for

800 mhz restoration
test mode
cellular freqs
From: MBramwel@business.uwo.CA (Mark Bramwell 519 661-3714)
Sender: daemon@ucbvax.BERKELEY.EDU
Bearcat 760XLT mods
From: <postmaster@whutt.UUCP>

Subject:    760XLT MODS
Subject: Bearcat Mods
Concerning the Uniden Bearcat 760xlt, the mod for the 950xlt does work
to restore lost freq. Disconnect pin 20 of the microprocessor from the
circuit board and connect it to pin 19. I bent the pin slightly and cut
it with the scissors of a swiss army knife then soldered an 1/8 lead
cut from a cap across the pins near the top of the chip. I've yet to
find any problem with this mod. But as always do so at your own risk.
73 Mike WA2E @ K2DLJ
                     RERUN...BY...GENE...N0KGX

Subject: RS232C Adaptor C/64-C128

I have been getting mail regarding the RS 232 adaptor, in that the message
has gotten scrambled. So, here it is again...

******************************************************************************

Here's a simple interface to connect a C64/128
to any of the multimode boxes on the market.

This circuit has been used between a C64 and
an AEA PK-232, and an MFJ-1270 TNC. Running
the Common Sense terminal program...........


C64/128           RS232 Adaptor            RS232C
====================================================
A&N --------------- Ground --------------- 1&7
B&C ------------- 2-7404-1 --------------- 3   RXD
  M ------------- 3-7404-4 --------------- 2   TXD
  H -------------------------------------- 8   DCD
  E -------------------------------------- 20  DTR
  K -------------------------------------- 5   CTS
  L -------------------------------------- 6   DSR

7404 is a Hex Inverter IC. Only two sections are used.
Pin 7 is ground. Pin 14 is Vcc. This is obtained from
the C64/128 RS232C port pin #2.....

Enjoy..............
73, Kraig  WB2PLW @ VE3SNPC64

BID: 16300_N0HME 
FROM: N0HME
SUBJECT: COMMODORE IC CHIP CHART

--QRX LYNN, LOADING MESSAGE (18)

  C64 IC CHART       
----------------------------------------

C-64 IC CHIPS PROBLEMS & SOLUTIONS

CURSOR JUMPS TO HOME POSISTION - 6510

ABNORMAL COLORS IN LETTERS - 82S100

DIFFERENT CHARACTERS DISPLAYED & CURSOR LOCKS UP WHEN TURNED OFF/ON -6510,6567

SYSTEM WONT RESET & +RESORE+KEY DOESNT WORK - 6510,82S100,901227-01

CURSOR DISAPPEARS AFTER WARM UP - 6526

+SYNTAX ERROR+DISPLAYS AFTER WARM UP -  ROM 901226-01

LONG PROGRAMS WONT LOAD & SYSTEM RESETS AFTER WARM UP - 6510,901226-01

KEYBOARD DOESNT WORK RIGHT AFTER WARM  UP - 6526,901226-01

CASSETTE MOTOR KEEPS RUNNING - 6510

CURSOR DISAPPEARS WHEN CASSETTE IS      PLUGGED IN - 6510

CASSETTE RUNS SLOW,PROGRAM SEEMS TO LOADBUT NOT RUN - 6510

BLANK SCREEN ON POWER UP -6510,6567,    82S100,8701

NO CURSOR,INTERMITTENT BLANK SCREEN,    INTERMITTENT GRAPHICS -6510

POWERS UP WITH +PRESS PLAY ON TAPE+     MESSAGE & THE DISPLAY BANKS -6510

CURSOR LOCKS ON POWER UP -6510

CURSOR GOES TO HOME WHEN+RETURN+IS      PRESSED AFTER RUN -901226-01

POKE COMMAND DOESNT WORK -901226-01

JOYSTICK DOESNT WORK RIGHT -6526

NO CHARACTER LETTERING IS DISPLAYED ON  THE SCREEN -6526,6567,82S100,901225-01

DISPLAYS GRAPHICS INSTEAD OF LETTERS -  6526,6567

CONTINUED IN FILE C64.3
DIGICOM

From: WB3JDI @ NM3G
Subject: C.A.R.S.DIGICOM BOARD MOD.
               MODIFICATIONS TO THE CARS DIGICOM BOARD
  
  FOR ALL THAT HAVE CARS DIGICOM BOARDS. THIS MODIFICATION WILL IMPROVE
  THE RECEIVE PERFORMANCE OF THE BOARD.
  REQUIRED PARTS:
  1. 18K 1/8 WATT RESISTOR  OR 75K
  1. 100K RESISTORS
  1. .0022  MYLAR DISC CAP.
  1. .047 DISC CAP.                                                            

  1. 2N3904 NPN TRANSISTOR
  3. .001  CAPS 
                                                                               

          RCV                    TOP VIEW
          ADJ
  :--------H--H--H--------------:
  :        H  H  H       FSK HH :
  :        H  H  H         0 HH :
  :        H  H  H              :
  :         R1    ========       X 1
  :                 2206         X 2
  :     ======= C1========  Z1   X 3
  :      2211                    X 4
  :     =======                  X 5
  :                              X 6
  :      0           0          :
  :     RCV  C2     PTT         :
  :                             :
  :-----------------------------:
   R1 56K             LIFT ONE END AND ADD 18K OR REPLACE WITH A 75K
   C1 .0018 OR .001   REPLACE WITH A .0022
   C2 .1              REPLACE WITH A .047
   Z1  5V ZENER DIODE   REMOVE  
continued in file digicom.2 - request from server
ALINCO DR110D 45w 2m mobile.  Remove top cover.  Cut YELLOW wire which loops
from left top corner of unit (just behind tuning knob) across the top of the
radio.  It is the only wire which is a complete 2" or so loop.  While holding
down the "F" and MHz" keys, power down the radio.  While still holding them
down, power up the radio.  It is now set for "out of bounds" reception.
    From : N7MYR @ N7JJY
      To : KJ6YT
    Date : 900728/2122
   MsgID : PY 10461@N7JJY, 717@KJ6YT $10461_N7JJY
 Subject : alinco mod

From: N7MYR@N7JJY

just want ed to reply to your message about the alinco mod. i just got the
answer i was looking for. thought i would pass it along to you.


mod for the alinco dr-110t
remove the top cover.
find the yellow wire at the front left corner (next to the tuning knob)
it makes a loop about 1 1/2 inches long.
clip the wire in two and insulate.
replace top cover.
reset the radio as per the manual. ( i.e.  hold f and vfo/m button down while
turning the radio on.
to change bands, press funtion followed by mhz button.
rig will change bands each time you do so.
this should allow reception from 130 - 169.995 mhz
the rig will also transmit from 103 - 169.995 mhz


hope this will help
73's from don in cheyenne
n7myr @ n7jjy

From: N7MYR@N7JJY

JUST WANTED TO LET YOU KNOW ABOUT SOMETHING THAT THE MOD DOES,
THAT I DIDN'T KNOW AT FIRST....

130-170 RECEIVE AND XMIT
340-380 RECEIVE ONLY
870-890 RECEIVE ONLY

AFTER YOU MAKE THE MOD ON THE YELLOW WIRE, YOU RESET THE RIG AS PER
THE MOD. THEN TO GO FROM 130-170 TO 340-380, YOU HIT THE F AND MHZ
KEY. TO GO FROM 340-380, TO THE CELLULAR 870-890, YOU HIT THE F AND
MHZ KEY AGAIN. TO GO FROM 870-890 BACK TO 130-170, YOU HIT THE F AND
MHZ AGAIN.

PRETTY NEAT.

JUST THOUGHT THAT YOU MIGHT TO KNOW WHAT IT WILL DO......
BEST 73'S AND C U LATER...
DON
N7MYR @ N7JJY
MOD FOR OUT OF BAND ENABLE PULL OFF TOP COVER , WITH RADIO KNOBS FACIHG YOU
LOOK BEHIND THE VFO KNOB AND YOU WILL SEE A YELLOW WIRE , LAYING ON TOP OF THE
VFO BOARD . CUT THE YELLOW WIRE AND TAPE END . REPLACE TOP COVER AND HOLD DOWN
THE F KEY AND THE VFO KEY AT THE SAME TIME AND TURN ON THE RADIO AND RELEASE .
HIT THE F & MHZ TO GET DIFFERENT RANGES OF RECEIVE. THE RADIO WILL HAVE TO BE
RE-PROGRAMMED. 
DR570T

MODS FOR OUT OF BAND ENABLE JUST PULL OFF THE TOP COVER, PLACE THE RADIO 
WITH THE KNOBS FACING AWAY FROM YOU. LOCATETHE LOGIC BOARD BEHIND THE 
FRONT PANEL. TOWARDS THE TOP MIDDLE OF LOGIC BOARD (IN THE UNSHEILDED AREA) 
ARE THREE WHITE COLOR JUMPERS, THE ONE ON THE LEFT TILTS ABOUT 45 DEGREES . 
YOU WANT TO CUT THE LAST JUMPER ON THE RIGHT (ABOUT MID-FRONT PANEL). 
REPLACE THE COVER . TURN ON THE RADIO WITH THE FUNCTION KEY DEPRESSED. 
THE RIG WILL KNOW HAVE TO BE RE-PROGRAMMED. FREQ. RANGE 130-170MHZ, 
420-470MHZ, RX ONLY 335-385MHZ, 850-890MHZ  
From: WW6L@WW6L
Subject: DRSI BOARD AND RFI

I recently had a conversation with DRSI, and in the course of things
the subject of RFI came up.  Here is some information you may find 
interesting and useful: The board is NOT GROUNDED THRU THE MOTHERBOARD,
BUT THRU THE METAL BRACKET.  (signal and electrical returns are, of course,
thru the motherboard, but not the connecting cable shield ground.)  This
is done to keep stray RF on the shield from being conducted inside the
computer case.  Those of you who don't always insert the little screw
may find that making a firm connection between the mounting bracket and
the case, and having the screws in the cover in place and tight, may
reduce or eliminate RF getting into the DRSI board and affecting the 
computer.  This also may reduce RF coming OUT of the computer, also.
73, Bob
                  RELAYED  BY...N0KGX...GENE

FL2100B

YAESU FL2100B 12 METER MODIFICATION
by Bill Walton KJ6EO

If you do not mind losing 10 meters on your FL2100B, this quick mod should
have you up and running on 12 meters with near full power output.

Place the FL2100B on its side with the LOADING control nearest the surface
that the amp is setting on.  Make sure that the amp has been UNPLUGED and that
the PLATE VOLTAGE has dissipated before you proceed.  Remove the screws that
hold the bottom cover on and remove the bottom cover of the amp.

Set the BANDSWITCH to : 10
Set the PLATE CONTROL to : 9
Set the LOADING CONTROL to: Fully counter-clockwise

Disconnect the 850 volt red wire that leads from the transformer to the DIODE
BOARD (located right behind the TRANS - OPERATE switch. Install a SWR bridge
between the EXCITER and the FL2100B.  Tune your HF rig to 24.950.  Turn the
FL2100B on and place the amp in the OPERATE MODE.  Excite the the AMP with an
AM signal, enough so that you can calibrate (set) your SWR meter.  Place your
SWR meter in the REV position and read the SWR.  While in the TX mode, tune
L206 (located near the GROUNDING WINGNUT just inside of the amp chasis) untill
you achive your lowest SWR reading.  You have just completed the retuning
proceedure of the 10 meter ANTENNA INPUT COIL.

If you would like to operate both 10 meters and 12 meters,  you may want to
tune L206 on a frequency between your operating fre-quencys on 10 and 12.

Re-solder the 850 volt red wire (with the AMP off and un-pluged). Re-assemble
the AMP and enjoy INCREASED POWER OUTPUT on 12 METERS.

Send questions, comments, or other to: KJ6EO @ KJ6EO
                   RELAYED  BY  N0KGX...GENE
ft101E

Add 12 and 30 meters to your Yaesu
FT-101,B,E,EE for less than $10. Send
a large SASE for a copy of the mod.
article from 73 Nov.1983. I have
performed the mod. on 2 FT-101B's with
great success. Address:
John Maetta
460 Milky Way
Lompoc,CA.93436

GL 73  John N6VMO...

    From : WB0SEN @ N0IFE.MO.USA.NA
From: VE3OSN@VE3JF
Subject: Final Mods - Yaesu FT 101E
Here's an old modification that's been around for a few years.  I had occasion
to use it recently myself, so it may be of value to someone else  I am not sure
of its origin, I may have picked it out of an old QST.  Anyway, it works.
73  -Bob-  VE3OSN @ VE3JF

FT209

de OE6RCD @ OE6UBG

FT 209 R /FT 209 RH Modification

It is possible to activate any 10 MHz segment between 130 and 160 MHz on the
FT 209 Handy from Yaesu. First you have to solder in the bridge 7 on the
control unit board ( pcb with the keypad ). Now after a reset the display 
shows you "0000" with the first digt flashing and you have to enter
the receiving low, receiving high, transmitting low and transmitting high
frequency (only the first 4 digits !). For example :
If you wish a receiving segment from 142.500 to 151.800 and a transmitting
segment from 144.000 to 146.000 MHz you must enter the follwing after the
reset :

       1 4 2 5  D
       1 5 1 8  D
       1 4 4 0  D
       1 4 6 0  D

Finaly you must programm the repeater shift. The shift is  n o t  set to
600 kHz. Enter  0 6 0 0 F shift. That's all !
	
The PLL locks only between 138 - 152 MHz successfully and transmitter 
works only between 140 - 149 MHz. If you want to use other frequencies
you must realigment the rig.
Best 73's de Roland, OE6RCD @ OE6UBG  or @ DK0MAV



From: N8XX@KC8TW
Subject: 9600 BPS with Yaesu FT-211RH
Path:       W9UUU!KA9LQM!WA4UMR!KF4NB!NK8T!KI4QJ!N8GTC!KC8TW

              - - - EVEN MORE NEWS FROM ACROSS THE POND - - -

From: RADio COMmunications, Radio Society of Great Britain, February, 1990
      Page 60.  Copyright 1990, RSGB, Reprinted by permission.

DATACOMMS - Edited by Neil Lasher, G6HIU

                         9600 BAUD MOD OF THE MONTH

This month the modification is for the Yaesu FT-211-RH.  Thanks for it are
due to Chris Lorek from SMC.

The FT-211RH has been shown to be suitable for 9600 baud packet operation.
There is no major surgery required just two screened leads are required, one
for TX AF the other for RX AF connected as follows:

RX AUDIO

On the RX IF Unit (sub board F2869104) connect the screened lead inner to
the TK10420 IC pin 9 with the outerscreen to pin 15.  Caution should be
taken to solder these if soldered to the underside of the board.

TX AUDIO

On the rear of the main PCB a small potentiometer will be seen (peak
deviation adjuster).  Unsolder the leg nearest to the rear of the set, and
connect the inner of the screened TX leads to this point, the outer to the
earth plane adjacent to this point.  To ensure that the 9600 baud modem is
terminated in the required impedance, it is essential that a suitable
terminating resistor be placed across the screened lead inner/outer, eg a
560 ohm resister; this may usefully be done at the FT-211RH potentiometer
connection.

No further adjustments need to be made to the radio.  On the tested modem a
suitable level of 2.5 kHz deviation was achieved with one third rotation
clockwise of the modem TX AF level potentiometer.
               RELAYED  BY..N0KGX...GENE
FT23R

YAESU FT-23R EXTENDED FREQUENCY RANGE:

'Circumcising' the FT-23R is remarkably simple.  Removing one solder
blob (pad #7, clearly marked, 10 o'clock position from the speaker, 9
o'clock from the microprocessor) lets the radio receive and transmit
from 140.0 to 163.995 MHz. The two circuit boards with surface-mount
components are uncluttered.  When opening the radio, be careful not to
lose the tiny coil-spring inside the battery-release button.  I
haven't measured receiver sensitivity, nor do I know about performance
in big-city RFI; the FT-23R is considerably more sensitive at 162-MHz
weather frequencies than is my modified Icom IC-02AT.
[source: W9MKV]
                        YAESU FT-2700
   --------------------------------------------------------------------
   D09 D10 D11 D12
     0   0   0   0     NO WORK
     0   0   0   1     AS SHIPPED
     0   0   1   0     -151.600
     0   0   1   1     144-154 MHZ  12/25
     0   1   0   0     -151.600
     0   1   0   1     144-148 MHZ  12/25
     0   1   1   0     144-154 MHZ   5/10
     0   1   1   1     144-146 MHZ  10/20
     1   0   0   0     -151-
     1   0   0   1     144-146 MHZ  12/25
     1   0   1   0     144-146 MHZ   5/10
     1   0   1   1     144-146 MHZ  10/20
     1   1   0   0     -151.600
     1   1   0   1     140.150      12/25
     1   1   1   0     144-148 MHZ   5/10
     1   1   1   1     144-154 MHZ  10/20
    -------------------------------------------------------------------
    -                        UHF SETTING                              -
    -------------------------------------------------------------------
    D13 D14 D15
      0   0   0        NO WORK
      0   0   1        430-440 MHZ  12/25
      0   1   0        430-450 MHZ  12/25
      0   1   1        430-440 MHZ   5/10
      1   0   0        *NORMAL* AS SHIPPED
      1   0   1        430-440 MHZ  12/25
      1   1   0        430-440 MHZ  12/25
      1   1   1        430-450 MHZ   5/10FT411

Subject: FT-411 OUT OF BAND MODIFICATIONS
Date: 08 Feb 89

 1) Open the front cover
 2) Locate the C.P.U. unit (it is located on the front cover ).
 3) Locate Jumpers 1,2,3 and 4 , These are the band setting Jumpers
 4) Jumpers No 1,2 and 4 should be disconnected ,and Jumper No 3 should
    be connected.
 5) Close the radio .
 6) Apply power to the radio and turn it on.
    The display will initialize with memory No 1 flashing and the
    frequency display will show 1.000
 7) Now , adjust the display to the desired lowest receive frequency
    When done ,press VFO.
    The memory CH will now show 2 flashing .
 8) Adjust the display to the desired highest receive frequency
    When done press VFO .
    The memory CH will now show 3 flashing .
 9) Adjust the display to the desired lowest transmit frequency
    When done ,press VFO.
    The memory CH will now show 4 flashing .
10) Now , adjust the display to the desired highest transmit frequency
    When done ,press VFO.
11) The rig is now set for your programed band on transmit and receive.
CONTINUED IN FILE FT411.4

FT470

Subject: YAESU FT-470 INFORMATION

Here are some measurements on the Yaesu FT470.
Measurements made with regulated 7.2 supply volts.
Power output measured with Bird and appropriate slugs.

TRANSMIT 2 METERS
------------------
LOW POWER-  RF OUTPUT: 1 WATT   DRAIN: 400 ma
HI  POWER-  RF OUTPUT: 3 WATTS  DRAIN: 700 ma

TRANSMIT 70CM
-------------
LOW POWER-  RF OUTPUT: 1 WATT     DRAIN: 550 ma
HI  POWER-  RF OUTPUT: 2.4 WATTS  DRAIN: 800 ma

RECEIVE
-------
As used below, "standby" means squelch closed, no signal received.

Note: When using "PRIORITY", "APO" is disabled, but "SAVE" still
functions.
Note: When scanning, both "SAVE" and "APO" are disabled.
Note: With squelch open (received signal), "SAVE" is temporarily
disabled.

SCAN or STANDBY, ONE CHANNEL: drain: 53 ma
SCAN or STANDBY, TWO CHANNELS: drain: 90 ma
STANDBY,"SAVE", ONE CHANNEL: drain drops from 53 ma to 10 ma
periodically.
STANDBY,"SAVE", TWO CHANNELS: drain drops from 90 ma to 10 ma, as
above.
STANDBY, "SAVE", "APO", ONE OR TWO CHANNELS: same as above.

AUDIO, ONE OR TWO CHANNELS: 50 - 150 ma

CONTINUED IN FILE FT470.3
FT-4700 Frequency expanding modification.
Following example shows programming for 138-174Mhz, and 420-460Mhz.

1. Remove front panel.

2. Locate jumper spots 1,2,5,9,10,13 and short them with solder carefully.

(Other jumper spots must remain as current on the control unit.)

3. Turn power on, and set the display for the lower edge of UHF band
(420.000),using up/down buttons, and dial. Then press D/MR
button.

4. Set the display to 460.000 and press D/MR. The display shows 47.75(if
frequency of uhf). Press D/MR, and then uhf coverage is programmed.

5. Set the display freq.  to 138.000 and press D/MR.  Then set to
174.000 and press D/MR again.  the display now shows the VHF if req.
at 17.3. Press D/MR again.  Now both band coverages are programmed.

6. After this modification the repeater shift is set to 000mhz, so it
must be set using the F and RPT buttons on both bands.  Re er to page
27 of manual for details.

7. Remember that transmiting outside the amateur bands is prohibited
unless you have a special licence.

73s to all and enjoy de Jimmy, SV0DR in Athens, GREECE
Subject: FT-726 AUDIO MODIFICATIONS

Further improvement in FT-726 audio quality can be achieved by a simple
modification to the product detector. The product detector seems to be
overloaded by the input IF signal, the 6dB attennuator described here
will improve the RX-quality
The circuit is proposed by LA8AK, and tested by LA7BI (Egil);

----------------- 1K --------------- to pin 5, Q13;uPC1037
I                         I
I                         I
T11                       I
output                   1K
link                      I
I                         I
--------------------------
      I
      I
     C67
     47nF( .047)
      I
      I
     --- pcb/ground
the two resistors (1000 ohms) are easily mounted below the PCB
Break the pcb between the coil and IC pin 5, mount the resistor, and
connect the other resistor from the capacitor to IC pin 5
The audio quality should be much improved, and you should at least be
capable of understanding somebody who does not exactly speak the same
language as you. Englishmen should now be able to read foreigners who
speak english, although it is well known that foreigners from different
countries who use english understand each other, but the englishmen
often do not understand them.
HI HI
73 de jan-martin
LA8AK  @ LA5IV 89 01 21 - 1828ZFT727R

YAESU FT-727R

Modification for extended coverage. (This will work for both the
old and new CPU versions)

    -Remove the battery pack

    -locate the RAM backup switch according to your manual ( this
     will be the switch FARTHEST away from the battery terminals)

    -Turn the switch off, count to 4, then turn it back on

    -Relace the battery pack

    -Turn the rig on. The readout should be entirely blank. If it
     is not, you probably did not wait long enough before turning
     the    switch back ON, so repeat the above procedure.

    -Type in the following:  ' 001111 '

    -The rig should now come to life.  You will have to reprogram
     all  the  memories as well as the repeater splits  for  both
     bands.  The display will now cover 100-199,  400-499MHz, but
     bands.  The display will now cover 100-199,  400-499MHz, but
     it  obviously won't work over this range.  Mine covers  139-
     153,  420-460.

     - The reset code is in your manual

[ From another source:
The factory code to make
the program from the factory is ( 443300 ) and if you enter those
digits the talkie will return to normal again. However if you enter the
code ( 601111 ) you will notice the talkie will come up in a different
mode you can and must input 5 digits instead of 4 to input a freq.

Example in the normal mode to get freq 147.06 you would enter 7060 then
        hit the dial button.

        In the expanded mode you would enter 47060 to get the 147.06 cause
        your display now takes and controls the last 5 digits of a freq
        instead of the normal 4.

CONTINUED IN FILE FT727R.1

Are there any mods for the Yaesu FT736R?

 I modified mine.  There's a catch tho - the mod involves adding a pair of
switches  to  the  module-address  lines into each of the rf modules..it's
kinda funky but it does work.  Look at your schematic, then  wire  up  the
switches  such  that  your  6m  and 2m modules *think* that they're 440MHz
modules!  The trick then is to look at the display, which reads 443.000,
and mentally adding 6.0 such that you know the real frequency is 49.000MHz.

 Similarly, the display will read 445.000 when the 2m module is really  at
145.000.  When  you finish adding the switches, you'll have to powerup the
'736 with the switches in the 'extended range' position.  Then use one  of
your existing memory frequencies, transferred to either the A or B vfo, to
then bandswitch up or down to the  440  band.  Bingo!  If  you  goof,  the
display  will  read "error".  Start over by powering down, and then repeat
the procedure. Sometimes the frontpanel logic will simply lock, just start
over and it will eventually work. Mine never takes more than 2 tries. With
the switches in the 'normal range' position the '736 will function as a
stocker.
CONTINUED IN FILE FT736R.1

-------------------------------------------------------------------------------
                    GENERAL COVERAGE MOD FOR YAESU FT-747GX
-------------------------------------------------------------------------------

1.)  Remove top cover.

2.)  On backside of display unit there is a brown jumper wire near the large
     ribbon cable.

3.)  Cut this jumper.

4.)  Turn radio on and set display for 12.345.6 then turn radio off then on.

5.)  This enables the general coverage mode and a GEN display will come on
     and stay on at the top of the LCD display.

6.)  Reassemble the unit.  It will now transmit everywhere it receives,
     however Yaesu recommends that it only transmit from 1.8 - 30 MHz.

             RELAYED  BY...N0KGX...GENE

FT757

de OE6RCD @ OE6UBG


FT 757 Filtermodification

During RTTY/AMTOR operation it is usefull to have an narrow filter 
to reduce QRM from other stations. It is possible to use the narrow
CW filter of the FT 757 for SSB, because of the shift/width system.

1.) Cut the connection between cathode of diode D 102 and a 150 OHM 
    resistor on RF UNIT. This resistor is not shown in service manual,
    but it exists on all rigs later LOT 4.
2.) Take a new diode (1N4148 or similar) and solder the cathode to the 
    open end of the 150 Ohm resistor. Connect the anode to middle 
    contact of a doubble pole toggle switch.
3.) Connect the OFF contact to pin 5 of J10 (SSB 8V) and ON contact
    to pin 8 of J10 (TX 8V).
4.) Take another Diode of the same type and solder it's cathode to
    pin 1 of J09 and the anode to ON contact of the second pole of 
    toggle switch.
5.) Connect the switching (or middle) contact of second pole to
    pin 7  of J10 (RX 8V). The OFF contact will be let free.

For the SPDT switch I am using the MOX switch on the front panel.
It is a 2 pole toggle switch and you habe to cut the PCB between 
the contacts. Further you have to remove all wirers to the MOX switch.
That's all.

Attention : There are some errors in the Service Manual. F.e the filter
connection is shown wrong. If you want to have a corrected circuit diagramm
or complete modification diagramm please write to Roland Robic OE6RCD,
Augasse 15, A-8430 Leibnitz, Austria.
Please enclose an A4 SASE ( 2 IRC or 4 IRC outside Europe Airmail)	
	 
This Modification should work also on FT757GX/II.

Best 73's de Roland OE6RCD @ OE6UBG or @ DK0MAV or you can write to
G3PLX AMTOR Mailbox.




FT767

        I have had my Yaesu FT-767 modified by the service facility for three
things:
        1.  Memory battery circuitry.  Previously the circuitry caused
        unnecessary drain on the memory battery, resulting in shortened
        battery life.  There is a kit available for this modification,
        which I ordered (free of charge).  After reading the instructions
        and not being able to even find the components involved, I took
        the unit down to LA to the service facility.

        2.  Hum mod.  I don't know anything about this mod.  It was
        performed while the unit was in for the previous mod.

        3.  DATA IN/OUT Jack audio control modification.  This mod was
        originated by me.  Since I have had the unit, I had not used it
        for packet because I could not defeat the audio from the speaker
        in any way without rendering the audio from the DATA IN/OUT jack
        unusable.  This jack was supposed to provide direct connection to
        the FM modulator and discriminator for packet.  It obviously was
        affected by the AF gain, external speaker disconnect, i.e., anything
        which affected the audio at the built-in speaker.  Examination of
        the circuit diagram seemed to indicate the audio for this jack
        came from the headphone circuit.

CONTINUED IN FILE FT767.2
Subject: YAESU FT767GX GENERAL COVERAGE MODIFICATION

CEO file contents:
I have recently purchased the aforementioned transceiver.  I have had
no
problems to speak of and enjoy the rig thoroughly. I would like to
submit the following mod for the rig.  Note that implementation on this
mod is at the rig owner's risk and may violate warranties.  Here is a
description of the mod:

- Remove two screws from the top near the front of the rig.
- Remove the bottom cover (8 screws: 4 underneath, 2 on each side)
- Remove the plastic rear panel.  (8 screws)
- Remove the rear metal panel.  (10 screws in back + 1 on each side)
- Loosen the "hinge" screws on the front bottom.  There are 4 of them.
- CAREFULLY lift front of the rig over the bottom watching as to not
  destroy the two bundles of wire that run vertically in the rear
  corners of the rig.  There are two power supply lines that need to be
  disconnected in the midst of this manuever; they have connectors near
  the power supply. (Remember to reconnect them on assembly.)  You will
  now notice that we have exposed a small circuit baord (the control
  board).  Underneath it is the one we want under the metal
  covering.  You may want to remove the two screws located near the
  front of the rig.  Note that this board is the same one that has the
  switch that allows changing the tuning dial from 5kHz/rev to
  10kHz/rev.
- Locate switch S01 and change its position.  The rig will now transmit
  from 1.5 to 29.99999 MHz.
- Reverse the disassembly procedure.

Well that's it.  You are now ready for any band addition that may come
our way.  If you have problems, reply; I'll try to answer your
questions.  73s de KA1TIH :   (Ken Chilton)R:880802/0618c 9178@WB0OIZ
[INDEPENDENCE, MO - 64050]
From: WB0OIZ@WB0OIZ
This is how to match the popular 75 ohm CATV hardline to a 50 ohm antenna:
          |                                                  |
          |        Overall Length 0.1628 (wavelength)        |
          |<------------------------------------------------>|
          |                                                  |
          |     75 ohm coax                50 ohm coax       |
          |     e.g. RG11/U                e.g. RG213/U      |
50 ohm----|{{{{{{{{{{{{{{{{{{{{{{----}}}}}}}}}}}}}}}}}}}}}}}}|----- 75 ohm
antenna---|{{{{{{{{{{{{{{{{{{{{{{----}}}}}}}}}}}}}}}}}}}}}}}}|----- xmission
           |                    | |  |                      |          line
           |<-.0814 wavelength->| |  |<--.0814 wavelength-->|
           |                    | |  |                      |
                                  |
                                  |
                                  |
                            Join using suitable
                                 connector
WB0OIZ
            RELAYED BY...N0KGX...GENE
IC02AT

    From : KC4MCQ @ N8GTC.IN.USA.NA
      To : MODS @ ALLUS
    Date : 900610/1416
   MsgID : BF 3895@N8GTC, 697@KJ6YT $25840_K6IYK
 Subject : ICOM AUDIO MOD
     Via : AA6QD!K6TZ!K6IYK!KB6JES!KB6GVT!W6TJ!AA6QN!N8GTC



        ===== AUDIO MODIFICATION FOR ICOM IC02 AND IC04 RADIOS =====
------------------------------------------------------------------------------

This audio mod works on the 02 and 04AT.  It increases the level of audio, as
well as rolling off some of the lows.  Sounds real nice. It involves the
circuit around Q105.

1.  Replace C119 with a .01 uF cap (disc ceramic is fine).

2.  Parallel R131 with a 1 uF cap (use a tantalum cap).

3.  Parallel R132 with a .01 uF cap (disc ceramic is fine).

This is not the same mod as the one International Radio is advertising, which
involves changing C117.

I tried an AB-1 Audio Blaster from Engineering Consulting, and was very
unhappy with the results.  I am very pleased with the audio given by this mod
(much cheaper too!).

                     ----------------------------------
CONTINUED IN FILE IC02AT.9
Subject: ICOM 02/03/04 & Vox Unit

The ICOM Family of Hand-Held Radios (02/03/04 AT) are well suited
for packet radio given the many available power supply options.

The big problem is getting the PTT to operate " CLEANLY " while
not compromising the audio level from the TNC when using the resistor
or resistor/capacitor interfaces suggested in some manuals.

I am using the ICOM HS10-SA Vox unit to interface the ICOM 02/04 AT
here.It has worked somewhat well for some time but I was always plagued with
a MINIMUM 200 msec transmit "hang " delay until I tore it apart for
examination and correction.

The small " delay " pot on the front of the unit is in series with a
2.2 Megohm resistor (R-19 on the board). The adjustable pot is also
about 2 megohms as well. This combination allows a MINIMUM VOX "hang" transmit
delay of 200 msec.

By identifiying the solder connections for R-19 on the back of the PC board
and placing a low value resistor ( or jumper )  in parallel....I was able to
achieve a ZERO "hang" transmit delay time with the delay pot in the FULL
COUNTER-CLOCKWISE position. The minimum 200 msec delay has been defeated.

73 Harold - N4KWB @ W4NVUIC04AT

    From : KC4MCQ @ N8GTC.IN.USA.NA
      To : MODS @ ALLUS
    Date : 900610/1416
   MsgID : BF 3895@N8GTC, 697@KJ6YT $25840_K6IYK
 Subject : ICOM AUDIO MOD
     Via : AA6QD!K6TZ!K6IYK!KB6JES!KB6GVT!W6TJ!AA6QN!N8GTC



        ===== AUDIO MODIFICATION FOR ICOM IC02 AND IC04 RADIOS =====
------------------------------------------------------------------------------

This audio mod works on the 02 and 04AT.  It increases the level of audio, as
well as rolling off some of the lows.  Sounds real nice. It involves the
circuit around Q105.

1.  Replace C119 with a .01 uF cap (disc ceramic is fine).

2.  Parallel R131 with a 1 uF cap (use a tantalum cap).

3.  Parallel R132 with a .01 uF cap (disc ceramic is fine).

This is not the same mod as the one International Radio is advertising, which
involves changing C117.

I tried an AB-1 Audio Blaster from Engineering Consulting, and was very
unhappy with the results.  I am very pleased with the audio given by this mod
(much cheaper too!).

                     ----------------------------------


[EOF]
                 Icom IC22S Packet Modification
      The Icom IC22S is a ten watt diode matrix PLL synthesized
     2 meter rig manufactured in the early 1970's. In it's stock
     condition it tunes 146-148 MHz in 15 KHz steps. Since I am
     sure there are a few of these sitting on shelves collecting
     dust due to the limited tuning range, why not modify them
     for the perfect packet rig.
      First replace the 7.68 MHz Oscillator/Divider crystal (X1)
     with a 5.12 MHz crystal. This will move the band to 145.00-
     146.94 MHz in 10 KHz increments. The repeater offset will
     now be 400 KHz which should not pose a problem in simplex
     packet operation. I will give the diode matrix settings for
     the most commonly used packet frequencies. You can formulate
     others as needed using the formula N=100*(f-145)+61 and the
     manual. The diode positions indicated ARE WHERE DIODES ARE
     PRESENT. The other positions are left empty.

             145.01= D5,D4,D3,D2,D1
             145.03= D6
             145.05= D6,D1
             145.07= D6,D2
             145.09= D6,D2,D1

      73's de Scott N5JLQ @ K6IYK Icom IC22S.MOD        Packet Modification
      The Icom IC22S is a ten watt diode matrix PLL synthesized
     2 meter rig manufactured in the early 1970's. In it's stock
     condition it tunes 146-148 MHz in 15 KHz steps. Since I am
     sure there are a few of these sitting on shelves collecting
     dust due to the limited tuning range, why not modify them
     for the perfect packet rig.
      First replace the 7.68 MHz Oscillator/Divider crystal (X1)
     with a 5.12 MHz crystal. This will move the band to 145.00-
     146.94 MHz in 10 KHz increments. The repeater offset will
     now be 400 KHz which should not pose a problem in simplex
     packet operation. I will give the diode matrix settings for
     the most commonly used packet frequencies. You can formulate
     others as needed using the formula N=100*(f-145)+61 and the
     manual. The diode positions indicated ARE WHERE DIODES ARE
     PRESENT. The other positions are left empty.
             145.01= D5,D4,D3,D2,D1
             145.03= D6
             145.05= D6,D1
             145.07= D6,D2
             145.09= D6,D2,D1
  
  73's de Scott N5JLQ @ K6IYK....RELAYED BY WB0SEN & N0KGX
>
IC24AT

There is a later version of IC24AT that does not require
D13 as in a previous bulletin. 
All programming of extended frequency coverage is available
from the keyboard.

To Enable extended freq coverage - 75 to 195, 200 to over 900 Mhz.
Hold down Light,  and B and turn on, wait for display to stop.
To enable 10 and 100 Mhz digit entry direct from keyboard:
Hold down light and 2 key and turn on, then turn off.
Hold down light and 3 key and turn on. 
Gud luck @ 73 Ron, N5WX

note from kc6hue @ ki6we:

I down loaded from your mods database ic24at. It stated that in order
to receive more, hold down light, b, and turn on. I did this and it
did not work. I contacted HRO and you need another key held down.
The # key must also be pressed... My radio now works...
AUDIO FIX FOR IC-27, 37, 47
Ed Richley KD9KZ fo Naples, FL has a very good article on
improving the audio treble and output power for these popular
mobile radios.  Capacitor C-67, from .01 to .00 uf and
Resistor R-31, from 150 ohm to 270 ohm, are the components
that are changed in the IC-27A two meter model and some
comparison to the 220 and 440 schematic should show if these
are the same parts in all three rigs.  So for more details
see Ham Radio Page 61 for Feb. 1986 and improve the one
complaint about this model.  I will do mine when time allows.
           RELAYED  BY...N0KGX...GENE

IC28A

ICOM IC-28A AND IC-28H

To make the IC-28 transmit 138-174 MHz, cut D21 (no retuning
required).  D21 is a tiny glass diode standing on-end near the center
of the upper circuit board, accessible by removing the top cover.  The
IC-28 is the only convertible ham rig  I know that covers the 170-MHz
federal government (including national park) frequencies.
+++++
+++++
ICOM IC-28A AND IC-28H

To make the IC-28 transmit 138-174 MHz, cut D21 (no retuning
required).  D21 is a tiny glass diode standing on-end near the center
of the upper circuit board, accessible by removing the top cover.  The
IC-28 is the only convertible ham rig  I know that covers the 170-MHz
federal government (including national park) frequencies.
+++++

IC2AT

If you own one of the IC2A, 3A, or O2AT series Hand-helds, you may be
interested in reading on.  I know my hearing is pretty good, but have you ever
tried to listen to the audio coming out of your speaker mike on the above
ICOM's? For the most part, it's pretty low.  I may be the last guy to figure
out a cure for this, but here it is anyway.  On the O2AT,etc., there is a
groove on the back near the top of the rig that is just the right size to
accept the HM9 speaker mike turned 90 degrees so that the mike plug fits in
that groove in the rear of the rig.  Thus allowing all the audio to be heard
from the internal speaker of the rig, usually much better than the speaker
mike.  Now, in the case of the 2A series, etc., the fix is more complex.
These rigs don't have that handy groove built in, so I decided a groove had to
be made to accept this configuration.  I thought long and hard about a minute,
before getting the "Dremel" out and making my own slot or groove.  It works
well on both hand-helds I have.  In fact,you can hook up an external speaker
for even more loudness in the auto.  So, give it a try or see me for a demo.
IC2GAT

FROM    : WB5RZX @ WB5RZX
SUBJECT : MOD FOR IC-2GAT

OUT-OF-BAND TRANSMIT MOD FOR ICOM IC-2GAT HANDHELD 2M TRANSCEIVER
(COPIED FROM PACKET RADIO; ORIGIN UNKNOWN:)

BACK SIDE OF DISPLAY BOARD: _____________________________________ 
|                          D505        |          D507  D504      ___         
|
           ___   ___     |___|                      |
|          |___| |___|                           --  + --
|   D506                    Q506           |           |
|    _O_------               _O_           |       HOLE FOR 
|   |___|     |             |___|          |       ON/OFF-VOL
|    O O      |              O O           |       CONTROL
|             |                |           |__________________
|              -----|<---------                              |
|          ADD DIODE: 1N914 OR EQUIV.                        |
|                                                            |

CONNECT DIODE BETWEEN TOP LEAD OF D506 AND LOWER RIGHT LEAD OF 
Q506 AS SHOWN.

NOTES: D506 MAY BE ABSENT.  IF NOT, REMOVE IT.
       RESET CPU IF NEEDED.
---

A FRIEND DID THIS AND HIS IC-2GAT CAN NOW TRANSMIT 138 TO 178 MHZ (NO 
RF POWER OUTPUT MEASUREMENTS WERE MADE).  HE DID NO RETUNING, AND DID 
NOT HAVE TO RESET THE CPU.  HE USED A TINY AXIAL-LEAD GLASS DIODE, 
REPLACED ITS LEADS WITH WIRE-WRAP WIRE, AND ENCASED IT IN SHRINK-TUBE.
THE OPERATION REQUIRES A SUPER-TINY SOLDERING IRON.  OBSERVE CMOS 
SOLDERING PRECAUTIONS: UNPLUG THE IRON AND GROUND THE TIP BEFORE 
TOUCHING THE CIRCUIT.

REMEMBER: EXCEPT FOR MARS AND CAP, IT IS ILLEGAL TO TRANSMIT OUTSIDE 
THE HAM BANDS WITH NON-TYPE-APPROVED EQUIPMENT.

----- END OF MESSAGE 973 FROM WB5RZX @ WB5RZX. -----RELAYED  BY  N0KGX...GENE

Hello I saw a message requestion mods for certain radios, and noticed that the
IC 2SAT was not on the list. But the 4SAT was.. Anyway, if you are interested
, I have a simple keyboard mod for the ICOM 2SAT. 

TO allow the radio to RX out of band with no limitations, except for the IF
limitations. This mod will allow you to dial in any frq from 0-1310 Mhz.
Naturally
this mod won't let you to RX from that whole intire range. the RX from this 
mod is typically from 100-200 maximum range. 

THIS MOD WILL ONLY WORK FOR THE ICOM 2SAT
'S THAT ARE ON THE MARKET TODAY. IN OTHER WORDS, THIS MOD WILL NOT WORK FOR
THE OLDER IC-SAT'S SOLD A COUPLE MONTHS AGO. 

To modify the IC-2SAT on RX, is a simple keypress of keys while turning the
radio on.

to Modify the IC-2SAT on RX, push the following keys.

"0","#","B","<light>" ----- WHILE TURNING THE RADIO ON.

this will open op the receiver.. TO MODIFY THE RADIO SO YOU CAN ENTER FRQ'S
DIRECTLY FROM KEYBOARD. THAT IS, THE WHOLE FRQ.

push the following keys, while turning the radio on.

"3","B","<light>" ---------- WHILE TURNING THE RADIO ON.

This mod. will allow you to dial any frq from 0-1310 MHZ.  for example if you
want to dial in 146.520 .. JUST GO INTO VFO and press the keys.
146520. AND THAT'S IT. !!


*****IF YOUR RADIO DOES NOT OPEN UP THE RX AT ALL******
*****THEN YOU HAVE THE OLDER VERSIONS            ******
*******************************************************

73'S BRIAN. REPLY BY SENDING -- SP N6VGJ@W8AKF.#SOCAL.CA.USA
IC3200A

Here is one modification that I found that will convert your ICOM IC-3200A
for operation on the 430-440Mhz band.
This is a very simple modification and does nothing to harm the radio,
no trace cuts, changing IC's or any of those problems.
The only minor problem is that you lose all your memories when it is
first done, so if you need to, wrtie those 2 meter assignments for re-entry
afterwards. Since the radio will only operate on the 430-440Mhz portion of
the UHF spectrum afterwards use on 440-450Mhz can only be done only after
the modification is cancelled.

Just inside the front panel of the ICOM IC3200A on the top there is a
circuit board that can be seen with the top cover of the radio removed.
There are several componets that can be viewed from this angle, look for
a jumper marked "J-8", this is for reference only.
CONTINUED IN FILE IC3200A.1




IC32AT

                    MODS FOR ICOM 32AT

1.  Remove battery and antenna.
2.  Loosen two screws on top of unit as much as possible without removing them.
3.  Loosen 4 flat head screws on bottom of unit 1 turn.
4.  Loosen 2 screws near PTT switch 1 turn.
5.  Remove 4 black screws on back of unit. 
6.  Lift bottom of front cover .25 inch, slide it down .25 inch, then lift
    front cover up 1 inch.
7.  Disconnect plug on 4 wires coming from the speaker. 
<< THe flex cable can be disconnected from the main board by gently
pulling up on the ears of the connector for that cable on the main board>>
8.  Lay front panel on table up-side down being careful of the flex circuit.
9.  All mods are done to the back of the front panel.  Notice places for 5
    axial diodes, which I will call 1 through 5, 1 being nearest the display.
<<These are on the right hand side of the back of the front panel>>
    Add/remove diodes so there are diodes in positions 3 and 5.  This will
    open up receive coverage for VHF & UHF and enable keyboard entry of the 
    10 MHz digit.
<< I seemed to have the same coverage with and without diode #3 installed>>
  
   When you go out of the range the radio will receive a U appears in
   place  of the memory channel number.  It means the PLL circuit has
   lost lock and the radio will not work.  

10. Notice 4 surface mount resistors slightly left of center directly
    above the speaker, lined up in a row.  Solder the anode (the side
    without the bar) of two diodes to the right side of the lower of
    the four resistors.
CONTINUED IN FILE IC32AT.6
AUDIO FIX FOR IC-27, 37, 47
Ed Richley KD9KZ fo Naples, FL has a very good article on
improving the audio treble and output power for these popular
mobile radios.  Capacitor C-67, from .01 to .00 uf and
Resistor R-31, from 150 ohm to 270 ohm, are the components
that are changed in the IC-27A two meter model and some
comparison to the 220 and 440 schematic should show if these
are the same parts in all three rigs.  So for more details
see Ham Radio Page 61 for Feb. 1986 and improve the one
complaint about this model.  I will do mine when time allows.
                   RELAYED  BY...N0KGX...GENE

IC3AT

If you own one of the IC2A, 3A, or O2AT series Hand-helds, you may be
interested in reading on.  I know my hearing is pretty good, but have you ever
tried to listen to the audio coming out of your speaker mike on the above
ICOM's? For the most part, it's pretty low.  I may be the last guy to figure
out a cure for this, but here it is anyway.  On the O2AT,etc., there is a
groove on the back near the top of the rig that is just the right size to
accept the HM9 speaker mike turned 90 degrees so that the mike plug fits in
that groove in the rear of the rig.  Thus allowing all the audio to be heard
from the internal speaker of the rig, usually much better than the speaker
mike.  Now, in the case of the 2A series, etc., the fix is more complex.
These rigs don't have that handy groove built in, so I decided a groove had to
be made to accept this configuration.  I thought long and hard about a minute,
before getting the "Dremel" out and making my own slot or groove.  It works
well on both hand-helds I have.  In fact,you can hook up an external speaker
for even more loudness in the auto.  So, give it a try or see me for a demo.
AUDIO FIX FOR IC-27, 37, 47
Ed Richley KD9KZ fo Naples, FL has a very good article on
improving the audio treble and output power for these popular
mobile radios.  Capacitor C-67, from .01 to .00 uf and
Resistor R-31, from 150 ohm to 270 ohm, are the components
that are changed in the IC-27A two meter model and some
comparison to the 220 and 440 schematic should show if these
are the same parts in all three rigs.  So for more details
see Ham Radio Page 61 for Feb. 1986 and improve the one
complaint about this model.  I will do mine when time allows.
         RELAYED  BY...N0KGX...GENE

LOW AUDIO FROM SPEAKER MIKE ON IC2A, 3A, 4A OR O2AT HAND-
HELDS
If you own one of the IC2A, 3A, or O2AT series Hand-helds,
you may be interested in reading on.  I know my hearing is
pretty good, but have you ever tried to listen to the audio
coming out of your speaker mike on the above ICOM's? For the
most part, it's pretty low.  I may be the last guy to figure
out a cure for this, but here it is anyway.  On the O2AT,
etc., there is a groove on the back near the top of the rig
that is just the right size to accept the HM9 speaker mike
turned 90 degrees so that the mike plug fits in that groove
in the rear of the rig.  Thus alllowing all the audio to be
heard from the internal speaker of the rig, usually much
better than the speaker mike.
Now, in the case of the 2A series, etc., the fix is more
complex.  These rigs don't have that handy groove built in,
so I decided a groove had to be made to accept this
configuration.  I thought long and hard about a minute,
before getting the "Dremel" out and making my own slot or
groove.  It works well on both hand-helds I have.  In fact,
you can hook up an external speaker for even more loudness in
the auto.  So, give it a try or see me for a demo.
         RELAYED  BY...N0KGX...GENE

ICOM M-700 Marine Transceiver

Despite that the literature says, no lock-out is employed.  For ham
frequencies on 40, 80 or 160 meters, set the mode switch to the hard
left position of "A3," to enable the lower sideband filter (all marine
HF uses upper sideband).

--
Frank  W9MKV
bitnet: reid@iubacs
arpa: reid@gold.bacs.indiana.edu   RERUN...BY...N0KGX...GENE

IC720

Transmitter is unlocked by snipping the light blue wire that's at the
very end of the top hatch cover to the left middle side of the
transceiver.
             RERUN...BY...N0KGX...GENE
IC735

  icom -735 unlock mod..........

 you simply cut diodes d33--d34

 that are standing on end near the

 microprocessor section toward the

 rear top of the radio............
 
 thats all..........
from wb1gob       RELAYED  BY  N0KGX...GENE 
IC745

IC-745 - PROBLEM:  TUNING COUNTS SLOWLY DOWN
I have a probnlem with my 745.  When I rang Bellevue, WA,
they said:  Never heard of it.  My friend in LA who has the
same pronlem got the same anser.  The problem is as follows:
The tuning counts slowly DOWN whether it's memory or VFO.  I
temporarily used the set by turning the dial in the UP
direction faster than the countdown and then used the lock
button when the set arrived on the desired frequency. The
XIT?RIT can be used for small corrections.  My friend who has
a complete professional lab at his disposal found a
temporary fix.  He grounded pin 40 of the I/O IC which steers
the CPU.  Everything workds fine except that you miss the
slowest tuning speed and that the UP/DOWN button on the mic
does not work.  I did the same and my set work the same.  The
tuning is a little bit coarse now but usable except you have
to be careful especially with RTTY or AMTOR.  The local ICOM
repair shop is too busy at the moment with their normal wo4k,
and I don't like to be without this set for too ong a time.
I can't use the 730 to drive my linear at least not without a
lot of trouble. I suspect thqt one of the two transisstors
has gone but which?  I just wonder if any of your readers has
had the same problem and fixed it.  (ED Note: Anyone have the
solution?)  (Thanks, Bob Bartelings, VE6CBN, 170 Haysboro
Crescent, Calgary, Alberta Canada T2V 3G3)
          RELAYED  BY...N0KGX...GENE
IC751

ICOM IC-751

Locate the RF board on the side of the radio and cut the black wire
going to pin 1 of jack 2.  Your transmitter is now unlocked.  (This
mod also described in _73_, July 1985 p. 12.)
           RERUN...BY...GENE...N0KGX
IC761

WIDER SSB BANDWITH ON THE ICOM IC-761 WITHOUT ANY
MODIFICATIONS
When in SSB mode and the filter switch is in the "out
position", your normal bandwidth is 2.6kHz.  When the filer
switch is in the "in position", your normal bandwidth is
2.4kHz.  I have noticed there is a 3rd SSB bandwidth for
receiving in the SSB mode.  Leave the filter switch in the
out position and place the IF shift button in the "in
position" for IF shift, and now the bandwidth is 3 to 3.2kHz
wide.  When using the filter switch only to select the
advertised wide and narrow position for SSB bandwidth, you
receive and transmit at those bandwidths and are using both
the 9MHz and 455MHz filters; however, when using the above
method as stated for the wider selectivity, it appears you
are receiving through the wide ceramic 455MHz filter only,
and bypassing the 9MHz filter.  So there are three positions,
not two.
       MODE       9MHZ           455           BANDWIDTH
       SSB        FL-80       CFJ-455K5          2.6
       SSB        FL-80       FJ-44A             2.4
       SSB        By Passed   CFJ-455K5          Approx 3.0
              RELAYED  BY...N0KGX...GENE
              ICOM IC-900 Out of Band Modifications
---------------------------------------------------------------------
BAND       OPERATING FREQ   MATRIX CIRCUIT LOCATION         CONDITION
----       --------------   -----------------------         ---------
28 Mhz     28 - 40 Mhz      Remove D33 (3-B)                RX Only

                            Remove D33 (3-B) &              TX/RX
                            Install Diode at 3-A
---------------------------------------------------------------------
50 Mhz     40 - 54 Mhz      Remove D32 (4-B)                RX Only

                            Remove D32 (4-B) &              TX/RX
                            Install Diode at 4-A
---------------------------------------------------------------------
144 Mhz    138 - 174 Mhz    Remove D27 (1-D)                RX Only

                            Remove D27 (1-D) &              TX/RX
                            Install Diode at 1-C
---------------------------------------------------------------------
220 Mhz    216 - 236 Mhz    Remove D26 (2-D)                RX Only

                            Remove D26 (2-D) &              TX/RX
                            Install Diode at 2-C
---------------------------------------------------------------------
CONTINUED IN FILE IC900.1
            

ICCIIV          
                     Computer Control of ICOM Amateur Gear
          
                              Carl Clawson, N7KBV
          
          
          
                              General Description
          
          
               Several ICOM products feature a built-in computer
          interface connected to a 1/8" phone jack on the rear panel.
          However, ICOM gives no information about this interface in
          the instruction manuals that I've seen.  The information
          exists within ICOM, and my dealer managed to get it for me.
          
               This interface, called the "CI-V" by ICOM, is standard
          on the following models:  735, 761, 275, 375, 475, and
          R7000.  Earlier models used the CI-IV parallel interface,
          which can be connected to CI-V by ICOM's UX-14 converter.
          Models using the CI-IV are the 751, 271, 471, 1271, and R71.
          The information I got from ICOM was written with the 735 in
          mind, but a listing of a BASIC program to control the R7000
          was appended.  I believe it will help with the other models,
          too.  The control codes and data format should be the same
          for all of them.
CONTINUED IN FILE ICCIIV.7
          
          
          
          
          
          
          
          
 
 
ICOM M-700 Marine Transceiver
Despite that the literature says, no lock-out is employed.  For ham
frequencies on 40, 80 or 160 meters, set the mode switch to the hard
left position of "A3," to enable the lower sideband filter (all marine
HF uses upper sideband).
--
Frank  W9MKV
bitnet: reid@iubacs
arpa: reid@gold.bacs.indiana.edu   RERUN...BY...N0KGX...GENE
ICR7000

   MODIFY YOUR ICOM R7000 TO SCAN AND SEARCH FASTER
                   Bob Parnass, AJ9S
This article describes how to  increase  the  scan  an
search speeds of the ICOM R7000 receiver by 60% without
noticeable performance degradation.

                      Background

The  front  panel  SCAN  SPEED  control  on  the  R7000
receiver  allows  the user to adjust the speed of scan-
ning and searching operations, as well as the  rate  at
which  the  priority  channel is sampled.  Rotating the
control counterclockwise decreases the speed, and rota-
ting it clockwise increases the speed.

When the SCAN SPEED control on my R7000 (serial  number
001400)  was  turned  fully  clockwise, the radio would
scan a maximum of about 8  channels/second,  or  search
about  8  increments/second.   As  the  following table
shows, the stock R7000 can scan  about  as  fast  as  a
Radio Shack PRO-30 or PRO-2003.

TABLE 1.  Maximum Scan Rates of Selected Receivers

 _____________________________________________________
[             Scanner               Maximum Scan Rate[
[                                [  (channels/second)[
[________________________________[___________________[
[ Kenwood TR-2600                [         1.2       [
[ Radio Shack PRO-30             [         8         [
[ Radio Shack PRO-2003           [         8         [
[ ICOM R7000 (stock)             [         8         [
[ ICOM R7000 (after modification)[        13         [
[ Regency M400                   [        13         [
[ Bearcat 20/20                  [        15         [
[ Bearcat 300                    [        15         [
[________________________________[___________________[

CONTINUED IN FILE ICR7000.3
ICR71A
          TRICKING THE ICOM R71A TO TUNE BELOW 100 KHZ

                        Bob Parnass, AJ9S


     The ICOM R71A general coverage receiver is designed for
     VLF reception down to about 97 kHz.

     The following steps will  confuse  the  microprocessor-
     based  controller sufficiently to permit reception down
     to 0.0 kHz:

       1.  If all 32 memory  channels  contain  frequencies,
           use  the FUNC and CLEAR buttons to clear a memory
           channel.

       2.  Place VFO/M switch into the M (Memory) position.

       3.  Using all the manual dexterity  you  can  muster,
           rock  the  MAIN TUNING knob back and forth, while
           simultaneously rocking the MEMORY-CH rotary  con-
           trol  to  switch  back and forth between a memory
           channel with a frequency in it and a clear memory
           channel.
CONTINUED IN FILE ICR71A.1
ICU2AT
*****************************************************************************
Extended TX mod for the Icom IC-u2AT 
This mod will extend the transmit range of the u2AT from 139 Mhz to
about 161 Mhz (maybe further if you adjust the PLL).  You'll be working
with a surface mount PCB, so you will need a fine point soldering iron
and a very steady hand.  And you will need one diode, like a 1N914, or
a tinyier one if you can get it.
You must have the service manual to help you identify where the new diode is
to go.  Review all the below with the manual before you reach for your
screwdriver and soldering iron!
>remove the battery pack.
>remove 4 screws that hold the sliding guide that the battery pack mounts on.
This is the piece of metal that frames the PL tone switches.
>remove the sliding guide. Be careful that you don't lose the battery release
button.
>there's a screw on the left side of the HT just below the light switch.
Remove it.
>CAREFULLY pry the front panel up.  There's speaker wires AND a flexable lead
that goes to the front panel.  
>There's a shielded PCB that these leads run to.  Carefully pry this up.  It
will then fold down.  There's several flexable leads at the bottom.  
>You should see the CPU now.
With the manual, locate where D113, D119, Q131 are.  
>Where the new diode goes is not marked in the diagram of the CPU PCB.  Locate
the anodes of D119.  This land connects to pin 27 of the CPU chip ic101.
Locate the cathode of D113.  This land connects to pin 20 of the CPU chip.
These diodes are SMDs, and do not look like what you'd expect diodes to look
like.
CONTINUED IN FILE ICU2AT.1
KAM

INSTALLATION of the TAPR "DCD STATE MACHINE UPGRADE" for KANTRONICS KAM


1. BROWN    Solder to the pad marked "X" near the top edge of the
           KAM'S board, near U25 by R96.


2. RED      Solder to the outer one of the pads of C53 near the top edge
           of the KAM'S board.


3. ORANGE   *** NOT USED ***


4. YELLOW    On the top of the KAM'S board inbetween U26 and R104 you will
            see the 20 pins of K8. Turn the board over and trace from pin
            21 of U26 (63B03X) to pins 7 and 8 of K8 and cut the circuit
            between 7 and 8. Then turn the board back over and solder the
            YELLOW wire to the pin of K8 that will lead back to pin 21 of U26.

5. GREEN    *** NOT USED ***


6. BLUE     Inbetween U5 and U2 solder to the end of R29 closest to U26.


7. VIOLET   Solder to the pad on the top of the KAM'S board inbetween R103
           and RLY1.


8. GRAY     You will find 2 pads on top of board inbetween U26 and U2,
           solder to the pad closest to pin 1 of U26.


 If you prefer not to view the RCV LED on the front of the KAM (which will be
on continuous) then cut the circuit that leads to L4 on the bottom of the
board.

Put the DCD Upgrade JMP across pins 2 and 3.
White and Black wires were removed, not used.

Works Great! de KA9UEX   RELAYED  BY  N0KGX...GENE

MC85

MOD FOR MC-85 MIC AND RC-1A PHONE PATCH
I am a Ham Radio Operator (call signed 4Z4MJ).  My station is
exclusively Kenwood (TS-940s, TL-922, TR-2400, TR-7950, MC-
85, and the PC-1A phone patch) and I'm very content of having
the honor to belong to the Kenwood family.
In Israel, I work as an electronic design engineer and on my
free time, I'm always anxious to solve design problems and
add my own modifications to the shack.  I would like to
present you the modifications I have made and hope they might
be helpful.  (The mods deal with the MC-85 microphone and the
PC-1A phone patch; I enclose them with this letter and
emphasize the changes with the yellow marker,  So let's
start........
When I purchased my TS-940S with the MC-85 microphone, I was
very happy with the 940 but sad about the 85.  The problem
was R.F. feedback when I was touching the microphone's goose-
neck with my hand, (or when the linear was on, it happened
without even having to touch the mic).  
CONTINUED IN FILE MC85.3
          ===== BAND EXPANSION MODIFICATION FOR ICOM MICRO2 =====

1.  Remove battery.
2.  Remove 4 screws securing batter.  Slide from fron panel.
3.  Remove small black screw below PTT switch.
4.  Carefully separate the fron speaker from the body by pulling front
    and rear down toward battery.  Flip it over.
5.  Next remove steel chassis assembly by gently prying up the sides,
    lift up, fold it down.
6.  Solder in new diode next to Q131 and Diode D113.  Looking at Diode
    Matrix with top of radio to the top,  add diode to the empty pad to
    the left of diode D119.  There are 3 points of connection on the
    diode pad.  Two on the left and on centered vertically on the right.
    The diode should be installed between the lower left and the right
    centered connection. (Arrow on diode points to right centered connection.)
7.  Reset CPU by following instruction manual page 23.

                     ----------------------------------

 ***->Be careful not to transmit out-of-band, or accidentally operate on
      any non-amateur, unless you are authorized to do so.

                      DO NOT JEOPARDIZE YOUR LICENSE!
               RELAYED  BY...N0KGX...GENE

MS400

Shared Interrupt Modification
-----------------------------

Purpose:
--------

This modification will allow a packet BBS using the CBBS, the W0RLI, the
KA2BQE, or WA7MBL V3.x code to install 4 ports using only one slot and
one interrupt request line (IRQ) on an IBM PC or compatible.  The change
is nondestructive since no traces are cut and can be easily removed.

Hardware:
---------

The DFI MS-400 board provides 4 ASYNC ports and is available from
several sources.  It comes in two flavors: XT and AT with the only
difference being the 8250 versus the 16450 chips.  As shipped from the
factory, the MS-400 requires one IRQ line per port.

Additional parts required are 4 small signal diodes (I used 1N914s
from Radio Shack) and a 4.7K resistor (1/8 or 1/4 watt).

JDR MicroDevices carries (or at least did so on Nov 1st, 1987) the
MS-400.  Their part number for the XT version is MCT-MS and it was priced
at $80.  Address: 110 Knowles Drive, Los Gatos, CA 95030.  Their phone
is (800)-538-5000 or (408)-866-6200 (for CA and non-US).
CONTINUED IN FILE MS400.4
ms6s.1

Modification of the AEA DX Handy Radios (Models MX-6S and MX-28S)
for Operation from External 12 volt Power.


1.  Remove the four black screws and plastic washers holding the front
panel to the radio frame.  Remove the front cover by gently pulling it away
from the radio frame.  Watch out for the wires going to the speaker and
microphone.

2.  Remove the OPTION switch by unscrewing the tiny black screws mounting 
it to the bottom panel.  Cut the white wire that goes up from the switch to/
the top of the board, and unsolder or cut the resistor going from the
switch to the grounded transformer can nearby.  The removal of the OPTION
swiônd its heatsink to fit 
against the bottom panel while the regulator sits parallel to the front panel.
This means that the heatsink will have a 90 degree bend.  Attach the heat-
sink to the bottom panel -- either with a tiny machine screw and nut, or by
loosening the other hardware on the bottom panel, and slipping the heatsink
between the layers of sheet metal.  Then retighten the other hardware.
I found that some versions of the 10 volt positive regulator come with a very
thin heatsink that makes this sort of installation possible.  The usual 7810
regulator heatsink is too thick, and screw/nut mounting is the only way.

CONTINUED IN FILE MX6S.1
              GET LONGER BATTERY LIFE FROM YOUR
              REGENCY MX-4000 OR MX-4200 SCANNER

                   by Bob Parnass, AJ9S

   The discontinued Regency MX-4000 and MX-4200 are  battery
   operated,  20  channel  scanners manufactured in Japan by
   AOR.  Both scanners contain a low battery warning circuit
   which disables the scanner when the battery voltage falls
   below a preset level.

   A freshly charged battery pack should  last  at  least  5
   hours  before  needing  a  recharge.   Ron  Smithberg, of
   Joliet, IL, complained of getting only 2 hours use from a
   set  of  freshly  charged  NiCd batteries in his MX-4200.
   This article describes how we increased his usage to over
   7 hours between charges.

   Both MX models are powered by a pack of 4 AA  sized  NiCd
   batteries.   The  battery pack is nominally 4.8 volts and
   has a rated capacity of about 500 mAh.  The scanner draws
   about  100  mA  when  squelched.  A good rule of thumb is
   that a NiCd should be recharged when  its  voltage  falls
   below  1.0 volts per cell.  Using this heuristic, the MX-
   4200 battery pack should be recharged when it falls below
   4.0 volts under load.
CONTINUED IN FILE MX4000.3
MX4200
              GET LONGER BATTERY LIFE FROM YOUR
              REGENCY MX-4000 OR MX-4200 SCANNER

                   by Bob Parnass, AJ9S

   The discontinued Regency MX-4000 and MX-4200 are  battery
   operated,  20  channel  scanners manufactured in Japan by
   AOR.  Both scanners contain a low battery warning circuit
   which disables the scanner when the battery voltage falls
   below a preset level.

   A freshly charged battery pack should  last  at  least  5
   hours  before  needing  a  recharge.   Ron  Smithberg, of
   Joliet, IL, complained of getting only 2 hours use from a
   set  of  freshly  charged  NiCd batteries in his MX-4200.
   This article describes how we increased his usage to over
   7 hours between charges.

   Both MX models are powered by a pack of 4 AA  sized  NiCd
   batteries.   The  battery pack is nominally 4.8 volts and
   has a rated capacity of about 500 mAh.  The scanner draws
   about  100  mA  when  squelched.  A good rule of thumb is
   that a NiCd should be recharged when  its  voltage  falls
   below  1.0 volts per cell.  Using this heuristic, the MX-
   4200 battery pack should be recharged when it falls below
   4.0 volts under load.
CONTINUED IN FILE MX4200.3
*****************************************************************************
Subject: Regency MX7000/MX5000 stop search function
here is a handy way to get the scanner to automatically
stop searching when it hits an active frequency and remain there until
it is re-started manually.  
With the scanner stopped on any channel using the MANUAL key, press
CLOCK SET followed by ENTER.  Now enter at least one numeric digit, but do
not press ENTER after keying in the digit(s).  Instead, press SCAN.
If you shut the scanner off, you will notice that the clock is not 
running.  The digit(s) that you entered is displayed.  Now use the
search feature as you normally would.  When it hears a signal, it will
stop and remain on that frequency.  After the signal ceases, pressing
any key that would normally give you an "error beep" (such as the ENTER
key) will restart the search from where it left off.  If you do not wish
to wait for the signal to go away before restarting the search, press
the UP key until it is gone, then press a key to produce the "error
beep."
To re-start the clock after you're through using the search-hold feature,
just use the normal clock-set method.  Incidentally, the priority feature
will not work if the clock is not running.
****************************************************************************
ms6s.1

Modification of the AEA DX Handy Radios (Models MX-6S and MX-28S)
for Operation from External 12 volt Power.


1.  Remove the four black screws and plastic washers holding the front
panel to the radio frame.  Remove the front cover by gently pulling it away
from the radio frame.  Watch out for the wires going to the speaker and
microphone.

2.  Remove the OPTION switch by unscrewing the tiny black screws mounting 
it to the bottom panel.  Cut the white wire that goes up from the switch to/
the top of the board, and unsolder or cut the resistor going from the
switch to the grounded transformer can nearby.  The removal of the OPTION
swiônd its heatsink to fit 
against the bottom panel while the regulator sits parallel to the front panel.
This means that the heatsink will have a 90 degree bend.  Attach the heat-
sink to the bottom panel -- either with a tiny machine screw and nut, or by
loosening the other hardware on the bottom panel, and slipping the heatsink
between the layers of sheet metal.  Then retighten the other hardware.
I found that some versions of the 10 volt positive regulator come with a very
thin heatsink that makes this sort of installation possible.  The usual 7810
regulator heatsink is too thick, and screw/nut mounting is the only way.

CONTINUED IN FILE MX6S.1
*****************************************************************************
Subject: Regency MX7000/MX5000 stop search function
here is a handy way to get the scanner to automatically
stop searching when it hits an active frequency and remain there until
it is re-started manually.  
With the scanner stopped on any channel using the MANUAL key, press
CLOCK SET followed by ENTER.  Now enter at least one numeric digit, but do
not press ENTER after keying in the digit(s).  Instead, press SCAN.
If you shut the scanner off, you will notice that the clock is not 
running.  The digit(s) that you entered is displayed.  Now use the
search feature as you normally would.  When it hears a signal, it will
stop and remain on that frequency.  After the signal ceases, pressing
any key that would normally give you an "error beep" (such as the ENTER
key) will restart the search from where it left off.  If you do not wish
to wait for the signal to go away before restarting the search, press
the UP key until it is gone, then press a key to produce the "error
beep."
To re-start the clock after you're through using the search-hold feature,
just use the normal clock-set method.  Incidentally, the priority feature
will not work if the clock is not running.
****************************************************************************
NETROM

Subject: How to CHANGE the CALLSIGN in the NETROM Software

THIS MOD IS NOT TO BE USED FOR PIRATING THE PRODUCT OF SOFTWARE 2000 
OR ANY COPYRIGHT PRODUCT OR MATERIAL.


A bit of History...

   When NETROM was first announced, most of the packet community realized that
it was another significant contribution to the growth of packet radio.
Contributions from the WA7MBL and W0RLI authors, the hundreds of digipeater
owners, sysops of countless PBBS's and "packeteers" who have DONATED their time
and efforts to packet, have been the backbone of packet growth.

   Despite the many complaints from many amateurs over the cost of the NETROM
"contribution", Digipeater owners once again dug deep into their pockets and
DONATED their efforts to the cause of Packet Amateur Radio and NETROM Nodes
have been appearing everywhere.

   Now with the emerging controversy over Nord-Link's "THENET" (a NETROM
"look-alike" being distributed FREE with source code for the Amateur community
to modify and improve), Mike Bush and Ron Weekes of Software 2000 (owners of
NETROM) have made harsh comments of theivery, etc.. towards Nord-Link for their
efforts. Amateurs who have viewed the code are questioning the validity of such
comments by Software 2000.
CONTINUED IN FILE NETROM.1
Date:  2 February 1985
From:  Headquarters, Indiana Wing/DC
  To:  Azden PCS-300 Owners
Subj:  Adjustment of PCS-300 PLL

One  of our members recently experienced a problem with his Azden 
PCS-300 handheld VHF transceiver.   The problem appeared to be  a 
failure  to  transmit  for  more  than a second  or  two  at  the 
beginning  of each transmission.   In actuality,  the  radio  was 
transmitting  but  the frequency was slowly drifting up to  about 
151 MHz.

After some correspondence with the U.S. distributor of the radio, 
the  following  cure  was found.   The problem  is  caused  by  a 
misalignment of the VCO in the PLL circuit.

There  are 3 circuit boards in the PCS-300.   Of course,  the one 
you want is the most difficult to get at, the one in the middle.

To  get  at the correct board,  first you must remove the  cover.  
Then  you  must remove 4 screws,  2 at the bottom of  the  radio, 
underneath the battery pack, and 2 more near the top of the radio 
between  the  top circuit board and the  heat  sink.   This  will 
enable  you to separate the radio,  but the plug-in cable to J101 
is  quite  short and must remain connected for you  to  make  the 
required  measurements.    If  you  will  turn  the  front  panel 
counterclockwise  about  1/8 turn,  you should be able to get  at 
transformer T104 which is quite close to R137.   The top  exposed 
end of R137 is TP103.

1.)  Turn  power  on  and connect digital  voltmeter  to  TP103.
2.)  Set frequency of radio for 142.000 MHz.
3.)  Adjust T104  until voltmeter reads 1.00 volts plus or  minus 
     0.3 volt.

PCS4000
                             HEADQUARTERS
                           NEW JERSEY WING
          United States Air Force Auxiliary, Civil Air Patrol
                    P.O. Box 16099, Building 34-34
               McGuire Air Force Base, New Jersey  08641
               (609)  723-8200           (609)  723-8205


Reply to                                                  15 May 1984
Attn of:  DCE/DCL

Subject:  Azden PCS-4000 Busy /Scan Mode Modification

     The following  is from LTC  Albert Beutler  (ZIGZAG 19).  He has
developed  a modification  that will  convert the  scan mode  to what
he calls  a more  conventional arrangement.  His  modification  is as
follows:
          "The Busy/Scan  mode of  the  Azden PCS-4000  scans until a
     signal  is  received, pauses  for  about five  seconds, and then
     resumes  scanning unless you are quick  enough to hit one of the
     keypad  buttons to stop  the scanning.  It is then  necessary to
     manually  restart the scanning.  This modification  converts the
     Busy Scan Mode to the more conventional arrangement in which the
     radio scans  until a signal is received, stops  scanning as long
     as the  signal is present, and then  resumes scanning about five
     seconds after loss of signal.  
CONTINUED IN FILE PCS4000.1


PK232
From: WB2ZTK@WB2ZTK
To: ALL@ALLBBS

Hello Out there....

I've just completed my work on the PK 232.  I mention earlier in the week
of a problem with the PK 232 regarding RFI and how the 13 volt supply line is
unprotected from accidentally placing voltages above 13.6 into that box.
This 13.6 v line is connected to a couple of IC and branch to many transistors
and is use as a pull up voltage for many circuits within the box.  

Well now that the highly stable voltage regulator in in place along with
a RF choke of 20 uH.  I can easly hear some of our checkins during 
the my Faxnet on 28.450.  The RFI from that box was of the low level type and
was knocking out the weak station when the unit was on.  

I am very happy with the addition for two reasons.

1.  It protect the PK 232 from Murphy and I.
2.  It gives my rig isolation from the RF that was leaking down the power 
    supply leads to a common power supply shared with the rigs and other
    devices.
CONTINUED IN FILE PK232.17
PK232SAT

The PK-232 can copy satellite telemetry from AO-13 and Uosat 9 and 11.  A minor
hardware modification is needed to copy Uo-11.  Satellite related bulletins
as well as satellite status reports are sent in plain text for part of each
telemetry frame daily on AO-13 and most days on Uo-9 and 11.

The following settings will copy AO-13 SSB Baudot RTTY telemetry which is sent
on 145.812 Mhz on the hour +15 and +45 minutes when operating mode B and on
435.651 Mhz on the hour +00, +15, +30 and +45 minutes when in mode JL:
     BA, RXR = OFF (mode B), RXR = ON (mode JL), WI = OFF, RB 50

The following settings will copy Uo-9 and Uo-11* FM AFSK ASCII telemetry on
145.825 Mhz (if not heard try 435.025 MHZ):
     AS, WI = ON, AB = 1200, (RXR is inoperative at this speed) 
     * The hardware modification discussed below is needed to copy Uo-11. 

Settings not listed are set to default values.
CONTINUED IN FILE PK232SAT.4
pk87

From: GM1FML@GB7MAC

In response to a question from G4BAU on how to upgrade a PK-87 to a PK-88
here is how. Mine and a few friends PK-87s all upgraded without any problems.

        UPGARDING A PK-87 TO A PK-88    12/02/89

      The first step is to discover which version of the PK-87 you have, the
difference lies in the crystal used in the clock oscillator. The old version
has a 2.4576MHz crystal while the newer version has a 4.9152 MHz crystal.

Items required :-     32k static RAM low power (e.g.HN62256LP-15)
                      PK-88 EPROM
PLUS for older
version of PK-87 :-   4.9152 MHz HC18/U parallel resonant crystal
                      220pF high stabilty capacitor

NOTE: There are two versions of the PK-88 to date. In the context of
  EPROM upgrades they differ in the device used for U 22 (in PK-88),
  the old version having a 74HCT4040 and the new a 74HCT4020. The
  4020 allows a slower clock interrupt rate this being selectable by
  jumper 7, because of this there exist EPROMs for both rates.
CONTINUED IN FILE PK87.9

I just purchased at AEA PK-88 TNC and discovered a few discrepencies in the 
manual. I'm sure a few other users of this fine product may have discovered the
errors also.

When I wired the TNC end 8 pin connector I followed the table in Appendix E. 
After completing the work I could not get the TNC to work properly in the loop
back test. I checked the wiring but compared it with the chart in Section 2.2.
I discovered the chart had pins 2 and 3 reversed to what was shown in the ap-
pendix. The chart is section 2.2 is correct. Do not use the chart in the ap-
pendix as a reference when wiring the TNC end of the cable.

The next error apparently is a typo in the preface. Look at the page titled
"Getting Started With the PK-88". It's the page before the one labled "i".
At the bottom of that page, locate the paragraph titled "Note to PC-PAKRATT
Users". The file name PCPAKRA87.CFG is not correct. It should be PCPAKR87.CFG.
Obviously you can't have 9 characters in a file name in DOS!!

The final problem I ran into was design error in the receptacle layout on the
back of the PK-88. The RX IN minijack is too close to the DB-25 RS-232 port.
It's an extremely tight fit with the respective plugs connected to those ports
to the point that  the minijack might get  damaged by the RS-232 cable con-
nector putting lateral pressure on the miniplug.
Dave
PRO2004
            6,400 CHANNELS FOR YOUR PRO-2004 SCANNER

                     by Bob Parnass, AJ9S

Chicagoan Denny Beringer sent in a few sheets he picked up at Dayton
describing a modification to expand the memory in the Radio Shack PRO-2004
scanner from 300 to 6,400 channels.

   The new circuitry adds 3 ICs, a 7 segment readout, a ribbon cable, a
pushbutton switch, and a few resistors and capacitors.

   First, diode D510 is added which expands the scanner from 300  to  400
channels. Then, IC504, the stock memory memory IC (a uPD446G), is removed and
replaced by a  ribbon cable leading to an added printed circuit board. The
additional board contains an HM62256 32Kx8 static RAM IC, which holds 16
groups of 400 channels each.  (note: if you don't do diode D510, I think
you'll get 4800 channels, though I haven't tried any of this. I heard that the
400 channel mod makes the markings on the 2004 keyboard incorrect.  WA2ISE)
CONTINUED IN FILE PRO2004.1
FROM WB0SEN TO ALL
SCANNER.MOD
Subject: PRO2005 scanner cell mod
SUBJECT: PRO-2005 mod
1. Unplug the radio
2. Remove the screws and take off the top cover.
3. Look for D502 on the inside right hand-side of the front panel.
   (No need to unsolder the silver plate protecting the vertical board!)
4. Simply cut the diode and reverse the process.
5. You now have complete cellular band coverage!!
Of course, according to the EPCA law, you are not allowed to listen to these
freqs.  The mod works for me.  Proceed at your own risk de KB2BBW.
RELAYED BY WB0SEN  &..N0KGX...GENE&...GENE

PRO34

From: wa2ise@kd6th.nj.usa.hamradio.org.iso (Bob)
Subject: Pro34 mod (detailed)

Disclaimer: I haven't tried this, proceed at your own risk WA2ISE.

                 "NOVICE NOTES" FOR PRO-34 MODIFICATIONS
 

1.  Remove the 4 small phillips scres on the back of the unit

2.  Remove the batter cover and battery holder from the case.

3.  Remove the two knobs on the top of the case (Volume &  Squelch)

4.  The Case has some pressure fit points, These are at the bottom of
    the case and you need to be a bit careful in forcing the two halves
    of the case shell appart. Once you have the pressure fit points 
    at the bottom released, angle up the bottom of the case until
    the battery sepperation wall is clear of the internal metal frame, and 
    slide towards the top of the unit, place the back half of the shell aside.
CONTINUED IN FILE PRO34.11
R:900823/2040z 4519@N3DFD.#PHILA.PA.USA.NA Z:19124. F:144.990.

I recently put out a bulletin for a fix for the Radio Shack model 12-140
Weatheralert radio concerning how to reduce the volume of the alert siren, but
leave the regular volume (broadcast rx) unaffected. I have recieved many
suggestions from many folks on packet, but I chose this one from Ed, KJ4LQ.

Remove the screws that hold the back onto the radio and look near the speaker.
You should see a capacitor (disk ceramic) identified as C31. (pcb silkscreen)
Lift the side of the capacitor closest to the speaker and place a 1 Meg. res-
istor in series between the leg, and pad to which it was connected. 

I used a 1/4 watt and spaghetti tubing and bent the resistor away from the pcb
on its leads (1/4"). oh....remove the pcb from the plastic standoffs to free 
the board from the top case to make it easier... after soldering the resistor 
place the board back in place and bend the resistor out of the way so as not 
to short out anything. re`assemble the radio. The siren volume willl now be 
reduced by about 75%, but the red alert l.e.d. will still flash as normal. 

You may also want to try a 1 meg trimpot in place of the fixed resistor should 
you wish to adjust the alert siren at will. (remember...if your in a high risk
area..like "Tornado Alley" in the Mid-USA, you may not want to use this mod 
since here in the East where I am, we don't get weather anything like they get
out there.

This will also void your Warranty from R.S.  Anyway...it works and has been in
use here for a few weeks now, left powered on, with no problems.

Thanks again for all the help from all!      (*.*)


Signed: George, WA2RCB @ N3DFD, Philadelphia, Pa.  19124. F:144.990.
RS232

Subject: Serial Port 9 pin to 25 pin Cable Adapt

DE9S                                           DB25P
Pin #           Control Signal               Pin #
1  DCD        Data Carrier Detect              8
2  RX         Recieving Data                   3
3  TX         Transmit Data                    2
4  DTR        Data Terminal Ready              20
5  GND        Signal Ground                    7
6  DSR        Data Set Ready                   6
7  RTS        Request to Send                  4
8  CTS        Clear to Send                    5
9  RI         Ring Indicator                   22

This pinout will work on any IBM compatable computer that has an 9 pin
connector.SCA
Additional Thoughts on SCA Reception: 

As I recall, the setup described by Bob Parnass (I think that was who it
was) was to hook a VLF receiver to the output of an ordinary FM receiver
to pick up SCCA (sic - I always call it that, Sports Car Club of
America, when it should really be SCA - Subsidiary Communications
Authorization or something!) transmissions multiplexed on ordinary FM
broadcasts.

To understand what is going on, you need to know what the FM station
actually transmits.

Let's do it in "top down" fashion.  All you computer jocks out there
should relate nicely to that.

First of all, the FM station has a "composite audio" input - this is
just the input on which SOMETHING (consider it a stub subroutine to
written later) is fed in to the modulator.

From the FM modulator's point of view, what you put on this input is
just the MODULATING SIGNAL which you want to Frequency Modulate (FM) the
station's carrier.  Intuitively, you can think of the station as putting
out a "pure" carrier at frequency F when this modulating signal is zero.
When it is NONZERO, however, the instantaneous frequency of the
transmitter is changed.  Say the modulating signal value, in volts, or
whatever, is M.  Then the transmitter output frequency is set to F + K*M
where K is a sensitivity constant which is unimportant except that
whatever maximum value of M is applied to the FM modulator input should
result in a maximum "frequency deviation" K*M which is just about the
maximum that the FCC allows.
CONTINUED IN FILE SCA.1
TAPR

From: K4DMU@WA4UMR
TAPR DCD mods - a review.


                       The TAPR DCD modifications.

                     A review by Joe Leitsch , K4DMU

        During the latter part of May and early June, 1989, I purchased

  constructed and installed four TAPR DCD modification kits- two of the

  XR 2211 Upgrades for an MFJ 1274 and Heath HD4040 (TNC 1 clone) and

  two of the State Machine Upgrades for a Kantronics KPC2 (which wound

  up in a Kantronics KAM) and an AEA PK-232. The following paragraphs are

  my personal experiences and thoughts on the project.

        I tackled the XR 2211 kits first. The only difficulty I encountered

  was an undocumented change in the pc board. There is an area on the

  upgrade board marked "J" that consists of two holes that are strapped

  with a piece of wire for VHF operation and which are wired to a 100K

  pot which adjusts the noise threshold when used on HF. Apparently there

  was a change in the board artwork after the assembly instructions were

  printed, because the "J" holes are CONNECTED by a printed trace on the

  solder side of the board. Therefore, for VHF operation, no jumper is

  needed, but if the threshold adjust pot is to be installed, the builder

  must cut the trace between the "J" holes for the pot to work. 

        Otherwise, the 2211 mod seems to work as advertized. I am able

  to run both TNCs on an unsquelched FM radio with no DCD action until

  a valid Packet transmission is recieved. This results in a quicker

  decode time for the transmission, and if the mod were made at both

  stations, a reduction in TXD time would certainly be possible.

CONTINUED IN FILE TAPR.1

---ten-tec argosy and mfj-1224 mods---

   i have several modifications for these
   units... the argosy mods involve using
   direct f.s.k. and are v-e-r-y simple..
   the mfj mods are to include a low-pass
   filter, a schmitt trigger and low tone
   freqs. if you are interested in either
   of these mods, send me an sase at my  
   callbook address..73 "jeff" wa2myl....RELAYED   BY...N0KGX...GENE
            KENWOOD TH-series HT TNC Interconnection

The  following is a suggested circuit for connecting a packet TNC
to a Kenwood TH-series HT.  Included is the TH-21/31/41,  the TH-
205/215/315/415, and the new TH-25/45 series HTs.

The connections are as follows:

     A  sub-miniature plug is used for receive audio.  The tip of
     this  plug  is audio out;  the sleeve of this  plug  is  the
     common ground for PTT, transmit audio, and receive audio.

     A  miniature stereo plug is used for transmit audio and PTT.
     Connect  the middle "ring" of the plug to the TNC audio  out
     through a 0.2 uf cap (for DC isolation).  Connect the sleeve
     of the plug to the TNC PTT. The plug's tip is unused.

Set  the  TNC audio for 50 to 80 mv audio output into  a  2K  ohm
impedance.TH215A

KENWOOD TH-215A handheld transceiver out-of-band modification:

1.  Remove two screws from belt clip
2.  Remove 4 screws from back of radio
3.  Slide front assembly off
4.  Locate set of 4 jumpers:
                              (top front inside)
                  +--------------------------------------+
                  $                                      $
                  $         +--------+                   $
                  $         $        $                   $
                  $         $        $                   $
                  $         +--------+                   $
                  $                                      $
                  $                      +--------+      $
                  $                      $        $      $
J4: intact        $           J4 o---o   $        $      $
J3: cut           $           J3 o) (o   +--------+      $
J2: cut           $           J2 o) (o                   $
J1: cut           $           J1 o) (o                   $
                  $                                      $
                  $                      SPKR            $
                  $                                      $
                  $             mic                      $
                  $             mic                      $
                  $                                      $
                  +--------------------------------------+

5.  Reassemble radio.
6.  Reset microprocessor:  Turn radio on while simultaneously pressing
    both _F_ key and _ENTER_ key.
TH25AT

The Mars & Cap mod for the Kenwood TH-25AT is to remove resistors R18-21.  They

are located on a panel under the display.  This one is a real pain to access
but
 this mod gives transmit coverage from 140-163 Mhz.  The TM-721A mod gives
trans
mit from 142-152 Mhz.
			MOD TO OPEN TX ON THE
			  KENWOOD TH-2600-A

        1. TO ACCESS THE 2600 LOOSEN THE TWO LARGE SCREWS ON THE SIDES OF THE 
           UNIT WITH A COIN.
 
	2. REMOVE THE 3 VERY SMALL PHILLIPS HEAD SCREWS ON THE BACK-SIDE OF
           THE UNIT
	
	3. REMOVE THE BATTERY.

	4. IN THE BASE OF THE UNIT YOU WILL SEE FOUR PHILLIPS HEAD SCREWS
	   REMOVE THE TWO THAT HOLD DOWN THE FRONT OF THE UNIT (SPEAKER SIDE)

	5. INSERT SCREWDRIVER INTO BASE & TWIST --YOU WILL HEAR A "POP" AS
	   THE TWO HALVS SEPARATE.

	6. CAREFULLY LIFT FRONT & LET IT TURN TO THE RIGHT, AS THERE IS A
	   RIBBON CONNECTION BETWEEN THE FRONT COVER & THE CHASSIS.

	7. IN THE LOWER RIGHT HAND CORNER OF THE P.C. BOARD YOU WILL SEE
           A ROW OF DIODES ON END (ABT 7), SNIP THE TOP TWO. (THEY MAY
           ALREADY HAVE A SOLDER JOINT, AS THESE ARE USED IN BENCH TEST)

	8. NOTE: THESE ARE DIODES D-32 & D-33 THE BOARD YOU ARE WORKING ON
                 IS X55-1380-10 A/2

	9. REVERSE THE PROCESS, & THERE YOU HAVE IT......
TH45AT

Subject: KENWOOD TH-25/45 OUT OF BANAD MODIFICATIONS

Here are some mods for the TH-25AT and the TH-45AT.  Please
note that I do not encourage transmitting on a frequency for which you
do not have a license, nor do I encourage transmitting on a non-amateur
frequency without FCC type accepted equipment (in the United States).

First let me recommend that you buy the service manuals for these
radios.  The service manual is not expensive (about $15 I think) and it
will greatly help you in performing these modifications.

Look at the schematic for your radio.  In the lower left hand corner is
an IC labled IC2.  This is an ASIC microprocessor.  At the lower right
hand corner of this uP are several diodes and pull-up/pull-down
resistors.  They are D4, D3, R19, R18, R28, R20, R21, R22, R25, R26, and
a couple of resistors that are not even on the schematic that attach to
B2 (pin 51 on IC2) and B3 (pin 50 on IC2).  The TH-45AT schematic shows
R23 on the ASIC uP pin B2.
CONTINUED IN FILE TH45AT.4
 Hi Ross,

I have a couple of mods that you may or may not have.  For the TH-75A MARS/CAP
mod, removing D4 will allow TX across entire tuning range, except that
actual TX range will be limited by tuning of the PLL.

For the TM-731A, there is a "Beyond MARS/CAP transmit Modification".  It
provides TX from 136 to 174 and 400 to 500 MHz.  Again, actual TX range limited
by PLL tuning.  If you don't already have this and would like it, I'll
send a copy if you furnish me your address.  It involves cutting R25 on the
control unit, and installing a jumper (diagram required to locate position),
then two resets in a row.

I have tested these mods on my own rigs.

73 - Kevin, KD2SL @ KC3BQ
From: N2EZG@KC2AZ
Subject: Paccomm Tiny-2 Factory Mod
Here ise "Factory" fix for Pac-Comm Tiny-2's & Micro-Power 2's
that have become hard of hearing.  It seems that Pac-Comm has some
boards out that work fine when new, but with age the tnc requires
a huge amount of Audio input from the speaker jack or it won't
decode properly.  They are lost as to what is deterioating in the
boards but offer this fix to its customers.
 It is quite simple and very neat, all parts are mounted on the under-
side of a 16 pin IC socket, the Modem chip TCM3105 (U16) is removed,
the modified socket is inserted into existing socket onC's board,
and the modem chip is re-installed.
Parts Needed:
1 - 16 pin IC socket
1 - 2222 Transistor NPN (EGC AP)
2 - 10000 ohm 5% resistors (brown-black-orange-gold)
							
Instructions:
 Solder 1 resistor to Emitter, other end of resistor to pin 12
 Solder 1 resistor to Base, other end to pin 2
 Solder collector to pin 5
                 RELAYED   BY...N0KGX...GENE

Subject: KENWOOD TM-211 OUT OF BAND MODIFICATIONS
   The following is a simple modification for the TM-221 rig:

     1- Locate the control unit board (X53-3040-XX) located behind the
        front panel.

     2- Right below the channel select rotary switch and opposite the
        M.IN Sw. you will find R24 and R25.(foil side)

     3- Remove R25 for 142.00 thru 151.995 Mhz RX TX

     4- Move R25 to space for R24 for 138.00 thru 154.000 Mhz TX RX
        (Range will vary slightly from set to set)

          Info provided by N2EYR @ WA2SNA-1 / Eddy Salvador

EXTENDED RANGE !!
TO GET YOUR 221A TO RECIEVE FROM 138-174 MHZ YOU
NEED TO REMOVE THE FRONT PANEL AND GAIN ACCESS TO THE CHIP RESISTORS
AND REARRANGE THENM AS FOLLOWS:

R22 R23 R24 R25
 X   O   O   X   X=CONNECTED  O=LEFT OUT

IF YOU ARE RUNNING A VK VERSION REMOVAL OF R24 IS ALL THAT IS NEEDED.
THE TX WILL REMAIN AT 144-148MHZ EVEN AFTER THE MOD.
GEOFF VK3KGH @ VK3RPA

A QUICK AND DIRTY FIX FOR THE KNWD TM231A LOW MIC OUTPUT TILL (IF)
KNWD COMES  OUT WITH A FIX IS TO BYPASS R 63 (3.3K).
R 63 AND R64 FORM A VOLTAGE DIVIDER AT  THE INPUT TO THE MIC AMP.
R63 IS ON THE BOTTOM OF THE RIG.  WITH THE BOTTOM COVER OFF AND THE FRONT
OF THE RIG FACING YOU, LOCATE THE MIC AMP BOARD 3610 WHICH STANDS VERTICALLY
OFF THE MOTHER BOARD.  FOLLOW THE 3RD PIN FROM THE LEFT TO R63.
A JUMPER HERE GIVES THE TX AUDIO A NICE BOOST.
BE SURE TO READJUST THE DTMF OUTPUT IN THE MIC (THE ONLY POT IN THE MIC).
73 AND GOOD LUCK. GREG.

From: N7LMJ@KB7CFD

 FROM: N0HME
SUBJECT: TM221/A MOD


GENERAL COVERAGE XMIT - TM-221/A

  1-REMOVE TOP AND BOTTOM COVERS, REMOVE LOCKING RING ON MIC CONNECTOR.

  CAREFULLY REMOVE PLASTIC COVER.
  2-PULL FRONT OF RADIO OFF (PLUG IN CONNECTOR)

  3-LOCATE THE CONTROL UNIT (XX53-3040-XX) 

  4-REMOVE THE SMALL RESISTOR CHIP FROM R25, THIS GIVES YOU XMIT FROM

  (142.000 THRU 151.995) 

  5-REPLACE THE SAME RESISTOR CHIP FROM LAST STEP ON TO THE SAME BOARD

  AT R24 WHICH IS EMPTY, THIS GIVES YOU XMIT FROM (138.000 THRU 154.000
) 

  EACH SET WILL GIVE DIFFRENT RANGE DEPENDING ON THE VCO SETTING, SOME

  WELL XMIT HIGHER THAN 154.000 AND SOME WILL SHUT OFF LOWER. THIS
 CAN BE CHANGED BY RESETTING THE VCO. 

                          RELAYED   BY...N0KGX...GENE

TM231A

From    : N4YJC @ N4LDG.#MIAFL.FL.USA.NA
              OUT OF BAND MODIFCATIONS TO KENWOOD TM-231A
              CONDENSED FROM INFO BY:PAUL SAFFREN --- N6NHH
THIS MODIFICATION WILL ALLOW TRANSMIT THROUGHOUT THE 136 TO 173 MHZ
RANGE. FIRST OF ALL YOU SHOULD BE AWARE THAT THIS MODIFICATION DISABLES THE
AUTOMATIC ARRL TRANSMIT OFFSET FEATURE.
   YOU WILL NEED A 1N914, OR SIMILIAR GLASS DIODE (NOTE: IF YOU HAVE A CHIP
DIODE OF SIMILIAR RATING, ALL THE BETTER!).
   IT WOULD BE A GOOD IDEA TO WRITE DOWN THE MEMORIES ON A PIECE OF PAPER, AS
DOING THE MOD ERASES THE MEMORIES.
REMOVE THE 4 BLACK PHILLIPS HEAD SCREWS FROM THE TOP AND BOTTOM BLACK
METAL SHIELDS.REMOVE THE TWO METAL COVERS.
NOTE: IF YOU JUST WANT TO MOD THE RADIO FOR MARS/CAP, JUST REMOVE THE 
TOP COVER AND CLIP THE GREEN WIRE JUST ABOVE THE VFO,MR,MHZ SWITCHES,
AND REPLACE THE TOP COVER. THIS EXTENDS TRANSMIT ABOUT 3 MHZ ON EITHER
SIDE OF THE HAM BAND. 
CONTINUED IN FILE TM231A.4
TM-2530/2550/2570 MARS/CAP
The TM-2500 series radios may be easily modified for use on MARS/CAP
frequencies from 141-150.995mhz.
Locate the control unit (X54-1860-XX) on the bottom of the radio.  This is
the same board that the TU-7, and or MU-1 are mounted on.  Just to the
left of IC3 you will find a row of diodes.  Cut diodes D8, and D11.  After
the diodes have been cut you will have to "reset" the microprocessor.
Microprocessor Reset.
1. Press and hold the [PS] key.
2. Turn ON the power switch.
3. Release the [PS] key.
All of your programmed data such as memory channel data, DCL data, and
Phone number data will be erased and you will have to reprogram them.  If
the radio is not reset, it will not recognize that you have cut the two
diodes.
        RERUN...BY...N0KGX...GENE
TM2530

TM-2530/2550/2570 MARS/CAP
The TM-2500 series radios may be easily modified for use on MARS/CAP
frequencies from 141-150.995mhz.
Locate the control unit (X54-1860-XX) on the bottom of the radio.  This is
the same board that the TU-7, and or MU-1 are mounted on.  Just to the
left of IC3 you will find a row of diodes.  Cut diodes D8, and D11.  After
the diodes have been cut you will have to "reset" the microprocessor.
Microprocessor Reset.
1. Press and hold the [PS] key.
2. Turn ON the power switch.
3. Release the [PS] key.
All of your programmed data such as memory channel data, DCL data, and
Phone number data will be erased and you will have to reprogram them.  If
the radio is not reset, it will not recognize that you have cut the two
diodes.
        RERUN...BY...N0KGX...GENE
TM2550

TM-2530/2550/2570 MARS/CAP
The TM-2500 series radios may be easily modified for use on MARS/CAP
frequencies from 141-150.995mhz.
Locate the control unit (X54-1860-XX) on the bottom of the radio.  This is
the same board that the TU-7, and or MU-1 are mounted on.  Just to the
left of IC3 you will find a row of diodes.  Cut diodes D8, and D11.  After
the diodes have been cut you will have to "reset" the microprocessor.
Microprocessor Reset.
1. Press and hold the [PS] key.
2. Turn ON the power switch.
3. Release the [PS] key.
All of your programmed data such as memory channel data, DCL data, and
Phone number data will be erased and you will have to reprogram them.  If
the radio is not reset, it will not recognize that you have cut the two
diodes.
        RERUN...BY...N0KGX...GENE
TM2570

TM-2530/2550/2570 MARS/CAP
The TM-2500 series radios may be easily modified for use on MARS/CAP
frequencies from 141-150.995mhz.
Locate the control unit (X54-1860-XX) on the bottom of the radio.  This is
the same board that the TU-7, and or MU-1 are mounted on.  Just to the
left of IC3 you will find a row of diodes.  Cut diodes D8, and D11.  After
the diodes have been cut you will have to "reset" the microprocessor.
Microprocessor Reset.
1. Press and hold the [PS] key.
2. Turn ON the power switch.
3. Release the [PS] key.
All of your programmed data such as memory channel data, DCL data, and
Phone number data will be erased and you will have to reprogram them.  If
the radio is not reset, it will not recognize that you have cut the two
diodes.
        RERUN...BY...N0KGX...GENE
more mods available in hardcopy only.
CONTACT CRAIG N7ETV @ WB6MQM.NV
Date:  29 August 1990

  To:  Radio Mod Server @ KJ6FY

From:  WA6YYM @ K3MC

Subj:  TM-431A Wide Band Transmit Modification



This modification allows the TM-431A transceiver to transmit and 
receive from 420.000 MHz through 444.975 MHz with essentially full
power throughout the band. 


1. Disconnect power

2. Remove top cover

3. Locate a green jumper wire sticking out of the front panel 
   assembly (behind VFO switch)

4. Cut the jumper in half and insulate the ends 

5. Assemble radio

6. This will reset the microprocessor and you will have to 
   reprogram all channels
TM701A
 
        TM-701A REPEATER CROSS-BAND MODIFICATION (REVISED)
				
				
Perform the following modifications to allow the TM-701A to operate in
the repeater cross-band mode.
 
 
MODIFICATION:
 
1.  Disconnect the power supply and antenna.
 
2.  Remove the top and bottom covers (12 screws).  Disconnect the
    speaker wire from the transceiver.
		
3.  Locate the green jumper wire show in figure 1.  Using a sharp pair
    of wire cutters, cut the jumper in half.(green jumper)
 
CAUTION: Cutting the green jumper allows the TM-701A to transmit from
         142 to 151.995 MHZ.  Protect your license by only using
	 frequencies that you are authorized to transmit on.
				 
4.  Solder a jumper wire to the foil side of the TX-RX board as shown
    in figure 2.
		
5.  Assemble the transceiver by reversing steps 1 -2.
 
6.  Reset the microprocessor by holding in the MR key as the power is
    turned on.
		
 
The repeater cross-band operation allows the TM-701a to receive on one
band and re-transmit the signal on the other band.  The TM-701a
alternately displays the two bands until a signal is received.  The
transceiver will then display the band that is re-transmitting the
signal.  The SHIFT function cannot be used during the repeater cross- 
band operation.  If the TONE or CTCSS function is required, only one ETA
tone can be used for the two bands.
CONTINUED IN FILE TM701A.2
tm721a - index of mods

file  	mod

1	cross band repeat
2	time out timer
3	new lcd readout 
4	cont from 3
5	mars/cap
6	freq range extend
7	cross band repeat operating procedures
8	wide band mod

        TM-731 FREQUENCY AND CROSS BAND REPEATER MODIFICATION
        =====================================================
 
    The TM-731a will transcive between 136-174 MHz and 400-500 MHz as
    well as perform cross band repeter function when the following
    modifications are performed.
 
    1.-  Remove both the  top and bottom cover. Disassemble the front
         panel such that the control unit (X53-3250-XX) is accessable.
 
 
    2.-  Remove R121, R123 and R25. While R125 snd R124 must be present.
 
 
    3.-  If the time-out timer function is not desired, remouve R122 as well.
 
 
    4.-  Reassemble the unit and perform a microprocessor reset before
         operating the set.
 
 
    5.-  Preserve your license by operating whithin the bands it is
         cover for.
 
 
                  BEST 73's
                  GERALD
 
TNC1

Switch Selectable Firmware on the TAPR TNC-1
  By Lynn W. Taylor, WB6UUT  

Recently, I was faced with a dilemma.  New TNC firmware
written by someone here in California offered some nice features
not available with the standard TAPR firmware, while new software
products for the Mac and supporting an earlier project required the
standard fare.  Switching EPROMs (even with ZIF sockets) still
required removing the screws in the case and reinitializing.

Studying the TNC design itself provided the answer:  The TNC
presently "bank selects" two sections of NOVRAM by switching the
high-order address bit.  If the existing 2764's in the TNC are
replaced with 27128's would double the ROM capacity of the TNC. 
Simply adding the high-order address bit to the NOVRAM bank select
would then allow two versions of TNC firmware to be resident
simultaneously, each with it's own bank of NOVRAM for operational
parameters.

The modification can be performed simply as follows: 

1)	Remove U5, U9, U10, U11 and U12.  
2)	On the component side of the board, follow the trace from U5
pin 21 to the via near the zero in U10 on the silkscreen. 
(note: a "via" is a small pad used to pass signals from one
side of a board to another).  Verify this by measuring
continuity from U10 pin 26 to the via, and from U5 pin 21 to
the same via.  
3)	Cut the trace entering the via on the component side.  I also
recommend cutting the same trace where it connects to JP-8 to
eliminate the possibly of noise problems.  
4)	Add a wire from the via to pin 17 of U27 -- the NOVRAM "bank
select" pin.  
5)	If you intend to bank select all 4 EPROMs (not necessary in
my case), add a wire from U9 pin 26 to U10 pin 26.  

CONTINUED IN FILE TNC1.1

TNC220

From: VE3PAZ@VE3JF.ON.CAN.NA
Subject: pac-comm problem with UO-14

Following message has been reformated from a binary file dump collected
from FO-20 by the automatic AMSAT station operated by ve3paz in Ottawa.
Hope this helps anyone over this way who is having the same problem

Hello All @ AMSAT
 
The following modification to the 220 will allow your Tnc to operate at
9600 bauds in Fullduplex. For those of you who thought you already could I
suggest you try it.
 
It must be mentioned at this stage that the version of my 220 is 1.3. If
yours is a different version then the story may be different, but I doubt it.
The reason for this mod is to allow my station to operate on UOSAT3 FULLDUPLEX.

---------------------------------------------------------
Previous to this mod I have been ripping my hair out as to why I could not
digipeat via UOSAT3. When one day I discovered that when I changed the
baud speed to 9600 and then put Fullduplex on the txbaud rate changed back
to 1200 whilst the rx rate remained at 9600. Most perculiar I thought.
CONTINUED IN FILE TNC220.1
This info is for those who requested
that I send it again and for those
who may have a TNC without a manual
which shows the wiring instructions.


                .
              .   .
              .   .

        FRONT VIEW OF DIN PLUG
            TNC CABLE

PIN NUMBERS FROM RIGHT TO LEFT ARE[

!   1-4-2-5-3




Ccmd:
?EH
Mailbox (B,H(elp),K,L,R,S) >
r3
Slot:3  To:ALL     From:N6QOG  01/28/90  21:10:21 MFJ to RADIO Connections

             KENWOOD 4 PIN

TNC                          RADIO

PIN 1                        PIN1
PIN 3                        PIN 2
PIN 4                        Speaker +
PIN 2                        PIN 3,4


             KENWOOD 5 PIN

TNC                          RADIO

PIN 1                        PIN 1
PIN 3                        PIN 2
PIN 4                        Speaker +
PIN 2                        PIN 4,5


             KENWOOD 6 PIN

TNC                          RADIO

PIN 1                        PIN 1
PIN 3                        PIN 2
PIN 4                        Speaker +
PIN 2                        PIN 6


            KENWOOD 8 PIN

TNC                          RADIO

PIN 1                        PIN 1
PIN 3                        PIN 2
PIN 4                        Speaker +
PIN 2                        PIN 7,8

CONTINUED IN FILE TNCPLUGS.1
From: N6QOG@K6RAU

Subject: KENWOOD TR-2500/3500 DIP SWITCH SETTING
The following is a list of the Dip
Switch settings for the Kenwood
TR-2500/3500.
It is mainly intended for those who
have the radio but lack the info.
              1=ON
              0=OFF
                            SWITCHES
FREQUENCY                 !1-2-3-4-5-6
---------                  -----------
 67.0                      1 1 1 1 1 1
 71.9                      1 1 1 1 0 1
 74.4                      1 1 1 0 1 1
 77.0                      1 1 1 1 0 0
 79.7                      1 1 0 1 1 1
 82.5                      1 1 1 0 0 1
 85.4                      1 1 0 0 1 1
 88.5                      1 1 1 0 0 0
 91.5                      1 0 1 1 1 1
 94.8                      1 1 0 1 0 1
100.0                      1 1 0 1 0 0
103.5                      1 1 0 0 0 1
107.2                      1 1 0 0 0 0
110.9                      1 0 1 1 0 1
114.8                      1 0 1 1 0 0
118 .8                     1 0 1 0 0 1
CONTINUED IN TR2500.1

here is some info on the kenwood model
tr-2600a handie - talkie....

if you want to be able to transmit on 
the extended freq area 
then do the following mod....
 1. remove the front cover of the radio

2. locate the ic chip in the lower
   right hand corner.

3. find the 2 diodes number d32 and d33
   (they should be the top two on the
   right side of the ic chip, also 
   they have ben cut beforenand 
  (re-soldered)

4. un-solder the two diodes (breaking
   their connection).

a5. replace the front ctver.

6. re-install the battery and turn the
   unit on, then push the reset button
   on the back.


the tr-2600a should now be reprogramed
and it should also transmit anywhere it
will recieve...

i forgot to add that d32 and d33 on the
recieve board (but that is what is 
under the front cover).

this is the mod as per kenwood....

hope you like it....


jim - kd0pj           RELAYED   BY...N0KGX...GENE

CIRCUIT MODIFICATION FOR KENWOOD TR7930/7950 TRANSCEIVER
              FOR PACKET/RTTY OPERATION
                      BY: WA4IXN

THIS MODIFICATION PROVIDES CONTROLABLE AUDIO OUTPUT
TO PIN 5 OF THE MIC CONNECTOR FOR SINGLE PLUG PACKET/
RTTY OPERATION.

REMOVE TOP COVER OF TRANSCEIVER AND CAREFULLY DISCONNECT
SPEAKER LEAD PLUG FROM "RX UNIT" BOARD.
LOCATE PLUGS"J-13" ON THE RIGHT FRONT OF THE "RX UNIT" 
BOARD AND "J-18" ON THE LEFT REAR SIDE OF THE BOARD.
NOTICE WHICH WIRE GOES TO PIN "8-M" ON "J-13" AND TO PIN #5
ON THE MIC CONNECTOR.
REMOVE PLUG "J-13" FROM THE BOARD AND LOCATE THE SPRING
TAB ON THE SIDE OF THE PLUG THAT HOLDS THE "8-M" CONN-
ECTOR IN PLACE.
USING A SMALL AWL OR POINTED TOOL, PRESS THE TAB DOWN
AND CAREFULLY PULL THE "8-M" CONNECTOR FROM THE PLUG.
WORK THE WIRE FROM THE HARNESS SO IT WILL REACH BACK
ALONG THE LEFT SIDE OF THE BOARD TO PLUG "J-18".
USING THE AWL OR SMALL POINTED TOOL, CAREFULLY SPREAD
THE "8-M" CONNECTOR A SLIGHT AMOUNT SO IT CAN BE FITTED
LIKE A SLEEVE OVER ANOTHER CONNECTOR OF THE SAME SIZE.
LOCATE TERMINAL "AP" ON PLUG "J-18".
CONTINUED IN FILE TR7930.1
TR7950

Just found a Kenwood screwup on the tr-7950. On the power-output
board where the PA module is connected is a 470 uf Cap designated
C 1. The silkscreen on the board shows the + terminal going to gnd.
The origional cap that was factory installed was installed with the
positive lead going to the + on the board. This is obviously wrong
as the Gnd Foil is the minus lead not the + lead. The cap had swolen
up and burst due to incorrect installation. Almost blew another cap
till I verified that the MINUS goes to the foil, not the way its
marked on the PC board. 
If you have a 7950 or 7930 you would do well to pull off the back
and inspect the Cap installed at C1. Its the only large filter cap
on this board so its easy to locate. If the case looks bulged, better
get another cap and install it correctly. 73, N5WX @ N5WX.OK

RELAYED BY WB0SEN....&....N0KGX..GENE...&...GENE

TS140S

From: KC4JCZ@WA4ONG
To: KJ6FY@KJ6FY

Hello from Richmond, Va. I noted your message about looking for a mod. Un-
fortunately I don't have that mod. I do have, however, the mod for the Ken-
wood TS-140S HF all band radio if you want it. Snipping diodes D29 and D31
not only will permit all-band, all-mode transmit, but it will also unlock
the 40 and 60 watt limit for FM and AM power max respectively.
 I am, however looking for a mods for the Kenwood 2m mobile rig (221 I think)
that will allow it to TX/RX up to 170 MHz or higher. I am already aware of the
mod for that rig where you snip the wire looking around the display to mod for
MARS/CAP (up to 151 MHz).
 Also am interested in a mod to unlock the Yaesu FT-212RH 45 watt mobile rig
for TX/RX up to 170 megs or higher. A friend would rather buy one of these
rigs than buy a mobile 2m and a marine radio. (he is aware of 25 watt ceiling
for marine).
Many thanks..will keep you informed of any future mods I hear of.
(P.S. cut diode D81 on Kenwood 440 HF rig for all-band MARS/CAP..almost
forgot!).
              73...de Bill KC4JCZ @ WA4ONG
                                    (aka RICBBS)


TS-2400 OUT-OF-BAND MOD.

LOCATE THE RX UNIT. 

Cut the DIODES D32 AND D33 LOCATED INSIDE THE DTMF IC.


Is this simple or what?!
TS430S
 
R:890220/1252z 321@VK2EHQ [via AMTOR KULNURA]
From: VK4ALV@VK2EHQ
MODS FOR THE KENWOOD TS430S FOR AMTOR. 
ABOUT THE TS430S,,THE MODS ARE AS FOLLOWS:- 
ON THE I.F.BOARD CHANGE C-164 FROM 0.22MFD TO 10NFD..50V CHANGE C-60 
FROM 10MFD TO 4.7MFD. 16V.... 
PARALLEL A 150KOHM RESISTOR ACROSS R.109 USUING A SMALL SWITCH OR 
BY WHATEVER MEANS YOU CAN DESIGN TO SWITCH THIS RESISTOR IN AND OUT. 
IN FOR ARQ AND OUT FOR ALL OTHER MODES. SOME PEOPLE USE THE SEND/REC 
SWITCH, OTHERS HAVE USED THE NOISE BLANKER SWITCH. I HAVE USED A 
SMALL MINI SWITCH WHICH I HAVE MOUNTED IN PLACE OF THE LEFT FRONT 
RUBBER FOOT. 
IT WILL PROBALY HELP TO CUT DIODE D-50 ON THE I.F.BOARD. IF YOU USE 
A 500HZ FILTER IN THE CWN OR SSBN POSITION THEN PARALLEL A 10MFD 
CAPACITOR ACROSS C-10 OR C-8. ADD A 10MFD CAPACITOR ACROSS C-161.(ACTUALLY 
I FOUND THAT THESE LAST TWO WERE NOT NECESSARY IN MY 430S.) 
YOU WILL FIND IT BEST TO TAKE THE AUDIO FROM IN FRONT OF THE VOLUME 
CONTROL, BUT THOSE PEOPLE USUING AUDIO FROM THE SPEAKER SOCKET SEEM 
TO GET OK RESULTS. REALLY YOU CAN GET AWAY WITH JUST THE FIRST TWO 
MODS, CHANGE C-60 AND C-164. THIS ORIGINALLY CAME FROM VK2AGE. 73S 
DE LARRY IN RAVENSHOE. 
TS440S

     These Instructions are TS-440 specific, but the basics also apply
to the TS-940, TS-811 and TS-711.

     It is possible to save yourself a few dollars and lose nothing in
quality by buying the parts to upgrade your Kenwood radio for computer
control. Just purchase the parts were you find them and install them
using the instructions in the Radio's Manual.

     IC 54 is a uPD-8251-AC   Serial Communications Interface.
                Commonly called an 8251A    ($1.89 Mail Order)
     IC 55 is a TC-4040-BP    12 Stage CMOS Divider.
                Commonly called a 4040      ($0.69 Mail Order)

     The IC-10 Interface Kit from Kenwood Contains ONLY these two parts
and less instructions than are in this file.  The only thing you are
going to miss, is the $22+ price tag on the IC-10 Kit.

 Signals are    TTL levels  (NOT RS-232)
Baud rate is    4800 (1200 Opt.)
   Format is    ASCII Serial;  1 Start, 8 Data, 2 Stops
   The Baud rate may be changed to 1200 Baud by removing jumper W50 and
installing a jumper from the left pad to the center pad as viewed from
the front of the radio.  This will become obvious once you have the
radio opened up.  Many other Baud rates are possible, just look at the
schematic.
CONTINUED IN FILE TS440S.20
SUBSCRIBER'S COMMENTS ON QRO MODIFICATION TO TS-830S, TS-530S
AND TS-530SP
I would like to pass on the problem I hace encountered in
connection with the QRO modification to the Kenwood radios
TS830S, TS-530S and the TS-530SP.
The problem occurs after many hours of long winded QSO's.  It
seems that with the increase in the screen voltage from 210
to 300 volts, R37 on the RF unit (#X44-1360-00) heats up
tremendously and will change it's value so greatly that even
the receive either suffers or goes out totally.  R37
originally is Metalfilm resistor at 3.3K ohms and is 1/2
watt.
I have changed mine to a Metalfilm as original same value but
have used a one watt resistor.  The brand I was abble to get
was RCA and I suppose there are better on the market.  This
is a 2% tolerance.  Three units that I know of have had this
problem that I took care of in this area alone.  Two units
were TS-830S and one a TS-530SP.  Just thought I would pass
that information along for what it is worth.  (Thanks, Frank
J. Lukas, Jr., 5301 Main Ave., North Ridgeville, OH 44039)
            RELAYED   BY...N0KGX...GENE

From: KC4JCZ@WA4ONG
To: KJ6FY@KJ6FY

Hello from Richmond, Va. I noted your message about looking for a mod. Un-
fortunately I don't have that mod. I do have, however, the mod for the Ken-
wood TS-140S HF all band radio if you want it. Snipping diodes D29 and D31
not only will permit all-band, all-mode transmit, but it will also unlock
the 40 and 60 watt limit for FM and AM power max respectively.
 I am, however looking for a mods for the Kenwood 2m mobile rig (221 I think)
that will allow it to TX/RX up to 170 MHz or higher. I am already aware of the
mod for that rig where you snip the wire looking around the display to mod for
MARS/CAP (up to 151 MHz).
 Also am interested in a mod to unlock the Yaesu FT-212RH 45 watt mobile rig
for TX/RX up to 170 megs or higher. A friend would rather buy one of these
rigs than buy a mobile 2m and a marine radio. (he is aware of 25 watt ceiling
for marine).
Many thanks..will keep you informed of any future mods I hear of.
(P.S. cut diode D81 on Kenwood 440 HF rig for all-band MARS/CAP..almost
forgot!).
              73...de Bill KC4JCZ @ WA4ONG
                                    (aka RICBBS)
TS711A

more mods available in hardcopy only.

FOR MORE INFO, CONTACT CRAIG, N7ETV @ WB6MQM.NV
more mods available in hardcopy only.

FOR MORE INFO, CONTACT CRAIG, N7ETV @ WB6MQM.NV
FROM: N0HME
SUBJECT: TS820 MOD

--QRX!--

--LOADING (2)--


 HERE IS SOMTHING YOU CAN DO IF YOUR
DIGITAL DISPLAY ON THE KENWOOD TS-820
IS GIVING YOU A PROBLEM..............

 1 -- REMOVE THE COUNTER ASSEMBLY UNIT
FROM THE 820.

 2 -- REMOVE BOTH CIRCUIT BOARDS FROM
THE COUNTER ASSEMBLY ( UPPER AND LOWER
BOARDS ).

 3 -- SCRAPE AWAY THE VARNISH FROM THE
CORNERS OF THE BOARDS WHERE THE 
INTERCONNECTING SCREWES AND SPACERS HOLD
THE BOARDS INTO THE CASE.

 4-- REASSEMBLE THE COUNTER....

 THAT SHOULD TAKE CARE OF THE PROBLEM..

 GOOD LUCK......

 BY--K0HRF............RELAYED  BY...N0KGX...GENE


TS830

here is an easy filter modification for the kenwood ts-830s. first to use 
this mod, your rig need the yk-88c and to mak  t even better, the yg-455c 
installed. in short what we are going to do, is move around a 9 volt 
switching voltage. this voltage comes from the af board, connector no. 7, 
pin no. 5. its marked rlr on the schematic. this voltage ends up at 
the pll assembly, connector no. 8, pin novp2. please do try this 
modification by cutting in this circuit at he source, because this 
same switching voltage feeds the if shiqo circuit, and the vbt circuit, 
and the pll. so cutting the wire at the af board will make the pll 
unlock when the mode switch is anywhere but in the cw positions. now 
to te prtceires.
1. remove the top and bottom covers, and turn the radio upside down with 
front facing you.

w2. locate the mode switch, and on the middle wafer set of contacts, 
cut the white wire with the blue stripe. it is located next to 
1the terminal with no conn ction, on the middle wafer set of contacts9)3-;3 
about 1/4 inch ox wire on t switch contact, so youcan make a connection 
there later.
CONTINUED IN FILE TS830.6
TS930
        ========= MODS for KENWOOD TS-930 Transcievers ==========

The following is a list of favorite changes that  can  be  made  to  the
Kenwood  930.  These  changes  are  quite  simple and do not require the
addition of any switches.

NOTE: In the operator's manual supplied with the 930, there is an  error
on  one  of  the  drawings. On the upper left corner of the DIGITAL UNIT
schematic locate connector 8. The lead designations are as follows (note
that some of the designations do not appear on this sheet so you can add
them to the drawing):

        Pin     Desig.
         1       100
         2       MU
         3       SCN
         4       M2
         5       MIN
         6       FSK
         7       B2
         8       FT

On the main drawing, called SCHEMATIC DIAGRAM, the pin numbers shown  on
connector  8  are reversed from the way they are numbered on the DIGITAL
UNIT schematic. In  the  following  changes,  I  am  assuming  that  the
numbering on the DIGITAL UNIT sheet is correct. In any event, it will be
obvious which end is which since the end pin is vacant.
CONTINUED IN FILE TS930.2
TS940

TS-940 - SUBSCRIBERS'S INQUIRY REGARDING DIGITAL DISPLAY
DISAPPEARANCE
I have a Kenwood TS-940S.  It has been operating perfectly
until just lately.
When you push the Power Button in, the digital display shows
but immediately disappears.  While it is in this mode, the
automatic antenna tuner does not function and, of course,
there are no signals coming in, but the voice synthesizer
reads the frequencies.  The last time I tried it with the
power button pushed in all the time was 2-1/2 hours before
any signals came through from the antenna.  Then it seems by
releasing the power switch and then pushing it right back in
again is the only way signals will come through.
Could you give me some idea what component would be at fault
or what is wrong or where to look for the trouble?  I do have
a Service Manual.  I have been a subscriber to the Kenwood
Newsletter for several years.  (ED Note:  We have seen this
problem many times.  Unfortunately we have no permanent fix.
However, the problem seems to go away if you unplug all the
connectors on the PLL and Logic Board to reseat them.
Perhaps one of our subscribers has found a permanent fix for
this problem??)  (Thanks, John Holmes, VE5YC, P.O. Box 6,
Colonsay, Sask., Canada SOK OZO)
                             RELAYED   BY...N0KGX...GENE

TW4100.A
From: VE4KV@VE4KV
Subject: BandMod for TW4100

The following modification will allow the TW-4100A to transmit on the
VHF band from 141-151 and on the UHF band from 420 to 450 MHz.

1. Disconnect the antenna, mic, and power cord.

2. Remove the top and bottom covers fromm the transceiver by following
   the procedure on page 28 of the Instruction Manual.

3. Locate the row of diodes on the control unit (top front). The 
   diodes can be seen by lookng throught the cutout the chassis just
   behind the front pannel.

4. Using a sharp pair of wire cutters, cut diodes D6 (UHF) and D8
   (VHF). Note that diodes D3, 4, 5, and 7 are already removed.

5. Reinstall the top and bottom covers.

6. Reset the microprocessor by turning on while pushing the M button.

Thats it! 

73s
Doug
N6OJN de W6PW-3 at 2151z - Last message: #5310. Next? >


hope this helps.. 73 de n6ojn steve, on treasure island

ADDITIONAL INFO AVAILABLE IN FILE TW4100A.1 - REQUEST FROM SERVER.
vfo-230 fine tune mod correction
 a note published in your t/k newsletter of january, 1983, issue no. 30, 
concerning a fine tuning mod for the vfo-230, impelledme to purchase a 
new vfo-230 for the sole purpose of obtaining a slower dial tuning rate 
for my ts-380s.  then the combination of a defective new vfo-230 and some 
bad information in your newsletter note triggered many, many hours of 
frustration and irritation over a period of several months starting in june 
1986.  i believe you should know about it when information in your newsletter 
causes frustration and irritation.
 i decided to try the diode cutting bit again.  it did not work.  
the optical dial encoder went crazy.  i was ready to explode and did.  
Fortunately there was nobody around to hear me.  back to the drawing board.  
now i know practically nothing about optical encoders but i do have an 
engineering background so i spent some time staring at the vfo-230 
schematic in the ts-830s service manual.  suddenly the light came on.  
ka0nnf gave you the wrong information about which diodes to cut.  
(his call is not wa0nnf as given in your newsletter note.  i tracked him 
down by telephone.  he told me he had sold the vfo-230 and couldn't remember.)
CONTINUED IN FILE VFO230.1
 
        MODIFICATIONS FOR THE WILSON MARK II AND MARK IV FOR CAP & MARS
 
      Please refer to the "Operating and Service Manual" for these radios.
      If you are having trouble getting MARS and CAP crystals to oscillate,
the following four steps should be taken:
                a. change C88 to 4pf.
                b. change C92 to 3pf.
                c. change C98 to 22pf.
                d. change C99 to 22 pf.
                e. Align T10, T11 to produce more than 1 volt on TP2
                   at both ends of the band.
                f. Align T12, T13 to produce more than 1 volt on TP3
                   at both ends of the band.
                g. Align L2 and L3 carefully to produce about the same
                   power output at both ends of the band.
                h. The radio should now be checked on a spectrum analyser
                   to insure clean operation. Of course the normal frequency
                   and deviation checks should also be made.
 
      For parts location on the circuit board, refer to the X-Ray view in the
   Operating and Service Manual.