I am sorry, I have no experience with such scopes. Maybe someone else here can give you some hints but maybe you should try to get a used scope like a Hameg.
Best regards, Dirk
Okay. Finally got an oscope - a used Tektronix 475 from ---- and it seems to work fine.
So how exactly do I read for the Vpp correctly? What I did was connected the probe at the PI input where a master volume would normally connect - I have decided to install this loop in a Fender AB165 style amp, so thwo channels both non-master volume and the third gain stage for both channels converge here at the plate of the third stage and go from plate to PI input's .1uF cap.
Assuming this is correct, I fed a 1kHz sine from a function generator iPhone app into the amp and ended up reading about 10Vpp at this area.
Does anyone know from experience if this is all correct?
Then if this is correct, I would break connection here and using the InB.
Thanks!