A question on Stasis S150

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I have slowly been rebuilding a Stasis 150. I have run into some unforeseen difficulties and had a question on what I should see on a scope with relation to the inputs to the transistors Q24 stasis N on the positive rail side and Q17 stasis P on the negative side. It looks like these drive the outputs. Am I safe to assume that I should see full signal at the input circuitry to the base of these transistors. My model is almost like this one except it doesnt have optical bias and a couple of other minor differences. schematic attached. The reason I ask is that I am only seeing a small positive going signal (no negative) for the outputs from the PCB to the output stage. Any suggestions on other places to test would be appreciated. I have a scope and function generator. The other minor thing is I have two schematics but neither one is completely accurate wrt the model I have. I am someplace in between (definitely not version 1 but pre 1988)
 

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