Review: Grundig Satellite 700 ----------------------------- Introduction At first glance the Satellit 700 looks similar to its predecessor, the 500. The styling of the case is the same, but the electronics inside are completely new. The case measures 30 by 17 by 7 cm and weighs 1.8 kilos without the 4 Size- D batteries which fit in the back. We think that puts the radio into the transportable category....not for the traveller who likes to keep things light and compact. If you want a radio that will deliver a bit of volume while your on holiday, let's say in a caravan, this is one of the radios you should consider. Coverage Like most portables, you can use this radio for medium, long, and short-wave reception, plus FM stereo. The set has only one speaker, so if you want stereo you have to use headphones or connect an additional matching speaker which is available as an optional extra. Long wave coverage is from 150-353 kHz on most versions, then there's a gap which is normally used by beacon stations. Medium wave coverage starts at 528 kHz goes to 1611 kHz where short-wave coverage takes over, and that's continuous until 30 MHz, slightly lower if you buy the set in Italy where there are some legal restrictions. FM is between 87.5 and 108 MHz, and the set claims to be the first portable with the Radio Data System, which means that the set displays the name of the FM station it is tuned to, at least in certain parts of Europe. Tuning It is easy to switch on the radio and do some simple tuning. But if you really want to discover the secrets behind the on-board computer you'll have to sit down for a couple of hours and read the instructions. A glance at the instruction book shows where the emphasis lies. There are 32 pages in total. Half a page tells you the frequency bands for broadcast listening, a half page on a few specifications, one and half pages are used to explain the connection of an external antenna and single-sideband, half a page on fine tuning. The remaining 30 pages are needed to explain how to program the radio to do all kinds of scanning, copy memories, timer functions and so on. The German and Dutch versions of the instructions are much better than the English one, which has clearly been translated by someone who hasn't a clue about short-wave terminology. That's a problem because you need a clear set of instructions to get to know this radio. It took me about three days to get the hang of it all..... That's not a criticism as such....if you want these programing features, they're all there. The Satellit 700 is clearly aimed at the serious short-wave hobbyist, selling at a price of 999 Dutch Guilders. Most of the development costs in the Satellit 700 have apparently gone into the design of the software. But let's look at performance of the radio itself as an instrument for picking up distant radio stations. For that we've done some extensive measurements in the laboratory, as well as listening tests in different parts of Holland, close to and more distant from our powerful transmitters on the Flevo polder. External Antenna If you use this radio at home, chances are you'd try to connect some sort of external antenna to the radio, even if its a piece of long wire dangling out of the window. The first thing you notice is that the internal ferrite rod antenna is always used for medium and long wave reception. You can't disable it, so you can't get rid of any in-house interference problems on medium and long wave, nor can you connect a directional loop. That we found surprising. When you switch in the external antenna, this becomes active above 1612 kHz. We've often commented that receiver manufacturers tend to make portable radios that are so sensitive once you attach an external antenna they simply can't handle the incoming energy and simply overload. As a result you get all sorts of whistles and stations popping up on parts of the dial where they are not really broadcasting. Measurements show that Grundig have solved this problem when you connect an external antenna to the 700. They've simply made the radio very insensitive. At 1.6 MHz you need 14 micro volts from the antenna to get a readable signal, at 4 micro volts the figure is 3.7 micro volts, at 8 MHz sensitivity improves, 1.9 micro volts are needed, at 10 MHz 5 micro volts, at 20 MHz 2.5 micro volts. These are figures for the AM wide position 20 dB signal to noise ration with 60% modulation. In the narrow AM filter, the sensitivity improves very slightly. Compare these numbers like 14, 4 and 2 micro volts with a communications receiver where figures of one micro volt are usually the norm, and look at the wide variation in sensitivity the Satellit 700 exhibits across the short-wave dial. Uneven Sensitivity The reason for this sensitivity anomaly lies in the sensitivity lies in a preselector circuit which has to be peaked for maximum sensitivity. The radio does this peaking for you as you tune around, but clearly it doesn't track with much accuracy. You can peak the preselector manually using the keyboard, which sometimes improves the sensitivity quite a bit, especially around 15 MHz. But having peaked the preselector manually, if you then turn the main tuning knob slightly, the radio switches back to the default preselector position, and the extra sensitivity is lost. We couldn't find any way to tune across the bands with maximum sensitivity. Single-sideband results weren't that impressive either. Sensitivity with the internal telescopic antenna is OK, better than one micro volt. That's because the signals picked up off the telescopic whip are put through a simple antenna preamplifier before being presented to the front end of the radio. Whilst the sensitivity goes up, the amplifier introduces all sorts of unwanted intermodulation products. Listening in The Netherlands to the 20 metre ham band, around 14.2 MHz, you can hear all kinds of broadcast signals, and these are internally mixed signals from the 41 metre short-wave broadcast band. Not what you need for trying to dig weak stations out of the atmospheric noise! The signal strength meter is simply a tuning guide. It doesn't correspond with real signal strengths because it doesn't start reacting until a very strong signal is heard. Audio Distortion Audio distortion is interesting to look at. In AM wide, the figure is an excellent 1.2%, in AM narrow the distortion is then 5%. When the synchronous detection mode is selected the distortion rises to 10%. On FM the distortion is very low. The internal speaker has a characteristic "German" sound when listening to short-wave. There's not much treble, but there's a heck of a bass response. In fact the audio amplifier deliberately boosts the bass frequencies to get chest thumping results on FM stations. The bass tone control doesn't do much to remove this if you don't want it. The radio has an intelligent tuning software package, so you can tap in a frequency very quickly. There's one bug though. If you are listening to an SSB station on let's say 13630 kHz and you then type in 13640, the receiver assumes you want to switch back to the AM mode. You can avoid this by using the manual tuning knob instead. Fine tuning only works in the single sideband mode, allowing you to adjust the frequency plus or minus 150 Hz. The steps in standard AM is 1 kHz on short-wave, and unless you switch to SSB or AM synchronous detection, you can't tune finer than that. That said, if you plan to connect a radio teletype decoder to the receiver, fine tuning in SSB won't be a problem. The automatic gain control is fair, but it seems to start working on signals that are too weak. Selectivity Selectivity is the ability of the set to pick out the station you want, and reject the rest. The set gives you two bandwidth choices when listening to broadcast signals. In AM wide the bandwidth is 6.8 kHz at - 6dB, and in narrow 4 kHz at - 6dB. The shape factor of the filters is excellent. In practice the maximum selectivity is around 65 dB because the synthesiser in the receiver generates a fair bit of noise. The synchronous detection system is an improvement over the Satellit 500, but, in our example, for some reason the detector is not symmetrical. The idea is that you tune in the station exactly. Let's pick Radio Austria International on 6155 kHz. Then you press the "sync" option on the keyboard. Now you can turn the tuning knob slightly to listen to either the upper or lower sideband, and in theory avoid strong interference from the BBC on 6160kHz (at some times of the day). When the bands are crowded that's often a method to escape interference from a station operating on an adjacent frequency. We can tune down as much as 1 kHz on the lower sideband side before the set loses its lock, but only 700 Hz in upper sideband, which is not enough to be really useful. The synthesiser remains locked on even the weakest signals, but if the signals are really weak then noise and whistles from the synthesiser itself become audible. A comparison with the newly launched Lowe HF-150 show that the sync detector on the Lowe is superior. The Lowe receiver doesn't have a lot of FM features on it though, and none of the memory tricks of the Grundig Satellit 700. The dynamic range of the Satellit 700 turns out to be only 66 dB which is OK for a portable, but not good when compared to the performance offered by communications receivers designed for real long distance listening. Radio Data System Feature We mentioned that the Satellit 700 has the Radio Data System on it. But the full advantages of this new system of tuning haven't been utilised. As with all RDS sets you need an excellent stereo signal before the station name is displayed, so this isn't a new way to identify weak FM stations. You can ask the set to display alternative frequencies for the same network, but you have to store these manually into the memories. And it's a shame they didn't use the RDS clock information to give the radio a super accurate self correcting clock. You can set a timer to record favourite programmes while you're out if you have a suitable cassette recorder. The main frequencies of 15 major international broadcasters are already programmed in the radio, and you can put another 64 stations in yourself, each with up to 8 alternative frequencies. The radio remembers the mode, and bandwidth selection, but not the preselector setting. If that's not enough, you can lift a flap on the front of the set and install extra memory chips to increase the capacity to over 2048 stored frequencies. Some clubs in Germany are co-operating with Grundig and selling pre-programmed chips for a very reasonable price with the latest frequencies of broadcast and utility stations programmed in to it. Power Consumption The set consumes a lot of power. At comfortable listening volume the consumption is around 200 milliAmps, so a set of 4 D cells will last 75 hours. You can also put in rechargeable cells and set the radio so that the cells charge up from the mains supply when the set is not in use. A fully charged set of nickel cadmium cells lasts about 20 hours, but it took the radio no less than 4 days before they were fully recharged! Not very convenient if you happen to be on holiday and want to do a lot of listening. Conclusions It is difficult to summarise the Grundig Satellit 700 in a few words. It is a full feature radio with endless possibilities. Its performance as a radio though is only fair, and certainly for a few dollars more the Lowe HF-150 is a much better short-wave communications receiver. But the Lowe doesn't have FM, scanning functions, or RDS. It is too complicated for the casual listener, and the performance will disappoint some people who expect a portable communications receiver. But if you're looking for features, there's nothing on the market at the same price £350, at least in Europe. It is up to you to decide whether these features are worth the price. .