- is a small or wide steady dance of the needle. Over a spread of one-eighth of an inch, say (depending on sensitivity setting—it can be half an inch), the needle goes up and down perhaps five or ten times a second. It goes up, sticks, falls, sticks, goes up, sticks, falls, sticks, etc., always the same distance, like a slow tuning fork. It is a constant distance and a constant speed. A theta bop means "death," "leaving," "don't want to be here." It is caused by a yoyo of the preclear as a thetan vibrating out and into the body or a position in the body. It's as if the needle is jumping between two peaks across a narrow valley. (EME, p. 16)
- a small or wide steady dance of the needle. Depending on the sensitivity setting it can be anything from one-eighth to half an inch wide. It is very rapid, perhaps five or ten times a second. (BIEM, p. 43)
- a diagnostic read, a sort of yoyo—in and out. It does not matter a continental how wide the theta bop is. It can be a whole dial wide. Most theta bops do it repetitively. One dip and one recovery at the exact same speed over the same area would be a one-motion theta bop. A theta bop has the equal halt at both ends. (SH Spec 1, 6105C07)