That kind of waveform is commonly caused by an open in the high
impedance vertical signal path before the first buffer. The
capacitance bridging the open circuit is enough when combined with the
high input impedance to make a high pass filter.
The output of the calibrator could be open causing the same problem
since it is looking into the high impedance input of the CA vertical
amplifier plug-in.
It also looks like the horizontal sweep is uneven.
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On 27 Mar 2016 22:42:35 -0700, you wrote:
Albert,
The voltage divider was a good idea. I was able to see the voltage across R330 as a sawtooth-looking waveform. The trouble is I couldn't get any leads into where the tubes were because the pins are very hard to get at. I did however look at the voltage across the anode of V384A and it seems to be the culprit because there was 0 V across the points that the manual says should have +123 V (when the horizontal position is all the way to CCW) and +325 V (when the horizontal position is all the way to CW). No matter what the horizontal position was, the voltage was 0 V. So I figured the tube was the issue. I replaced the tube with an equivalent 6DJ8 and it seems to have fixed the half screen problem! However, the waveform shown is off. It could be due to calibration being way off so it might be an easy fix. But I am feeding Channel B the calibrator square wave and it looks very off. It doesn't look square first off and also, it has this spot in the middle that seems to be different than
the rest of the signal. Picture: Imgur: The most awesome images on the Internet
David Hess