Hi Kevin,
In XY mode a vertical signal is not really needed but it looks nicer. Simply defocus the spot and set it to a convenient brightness. The idea is that you can watch DC voltages now with your DMM while you slowly rotate Hor Pos from fully counter clockwise to fully clockwise and back. You might find for instance that the first stage (test points 85 and 86) follows the Hor Pos knob position smoothly over the whole range from 2.1 V to 4.1 V, while the second stage fails. It might be normal that the Hor Pos even goes slightly beyond these extremes of the sweep.
Albert
---In TekScopes@..., <kcrossett@...> wrote :
Hi Albert. Appreciate the advice. I have checked the XY mode, but only with
no signal. The dot near the middle does move slightly, but only about a
half-an-inch or so. I don't have any way locally to create a triangular
wave form, and I don't have, or know anyone, with a second scope to use for
testing. I hope I don't need to desolder any of the transistors to check
them out. That would require some extensive disassembly, as far as I can
tell from looking at the physical component locations.
