looking for biphasic square wave image tia sal2

Basically a pulse train that has both positive and negative peaks.

If you mean biphase coding, it goes something like this: (use a fixed pitch font like courier if it looks garbled) 1 0 0 1 1 0 data | | | | | | | timebase

-. .-. .---. .-. .- | | | | | | | | wave | | | | | | | | `---' `-' `-' `---'

AIUI it's similar to manchester coding, notable features are that there's a state transition in the middle of every bit, and between dissimilar bits, and that for bitrate b most of the energy is between 1/2b and b Hz Bye. Jasen

Is this in regards to Robert Beck's little circuit? It's just a square wave that swings from +1volt to -1volt (that is, it has no net DC offset.)