Hi Jon,
? I was hoping to have a newer version of the old 1A1 preamplifier that has an switchable output for A, B, and A-B. ?I can get an old 1A1 but the power supplies, such as the 127, are very hard to get. ?There was an updated pre-amp, I think 1A7A but again you need the power supply.
? I think I can use a differential probe to do the same measurements so I am looking at taking that path. ?
Regards,
?Mike?