VCRs (if playing tape) would be the least recommended signal source for troubleshooting...Especially sync troubleshooting.

VCRs record the complete signal on tape and play it back...As such the most minute lack of precision in the mechanical systems results in sync errors in the VCRs output. Sets made before 1970 were not made with VCRs in mind and will have a harder time correctly syncing to tape than say an 80's TV set, but even the newer sets will show some errors if the signal is bad enough.

Use a DVD player, OTA DTV/cable/sat converter or test pattern generator for troubleshooting.

If your DVD player lacks RF output then you can plug it's A/V output into the VCRs A/V input, tune the VCR to it's A/V input and use the VCR to RF modulate the DVD signal. The VCR should not cause sync issues as long as you do not use it to play videotape.

Hello again. I used a DVD player, and ran it through my VCR to get these signals. Sorry about the extra trace in the pictures. I couldn't figure out how to make it disappear. I appreciate all the help so far, and could use some feedback as to where to go from here.

Photos #1 and 2: Output of first sync amplifier. About 60 volts. Probe X10, Scope X2 scale.

Photo #3: Input to sync separator. About 25 volts, which would be low. Should be 35 volts. Probe X1, Scope X5 scale.

Photo #4: Output of sync separator. About 80 volts. Probe X10, Scope X5.

Can you explain why you have two waveforms for the output of the first sync amplifier? H and V rate? Neither one looks very much like the waveforms on the schematic. The first one, that appears to be H rate, appears to be inverted compared to the schematic.

Picture 3, input to sync separator, seems to have a lot of video. (On the schematic, it shows mostly sync pulses with a little video leaking through.) As a result of the excess video, the output of the sync separator has a lot of video also - it should be purely sync pulses.

I would start by checking the first sync amplifier. Check DC voltages. Check component values. Do you have a known good tube to substitute?

I must have been rushing. I hope these pictures are more helpful. I'll follow your advice and look for the problem in the sync amplifier section. I'll look for another tube. I bought a replacement for that already, but didn't check it on my tube tester. I'll do that today. Here are new pictures taken today.

Photo #1: Plate of D-C Restorer. It's 15 volts, and should be 9 volts.

Photo #2: Output of first sync. amp. It's 75 volts, and should be 35 volts.

Photo #3: Input to sync separator. It's 32 volts, and should be 35 volts.

Photo #4: Output of sync separator. It's 90 volts, and should be 75 volts.

By the way, I enjoyed looking at your webpage, especially the World's Fair section.

Did you download the Rider manual? In case I wasn't clear, that's the one with the waveforms I have been referring to.

When you say output of first sync amp is 75 volts, is that 75 DC or peak to peak?
Schematic says the plate (pin 8) DC should be between 163 and 185 v dc depending on picture setting. Peak to peak should be 40 volts pp horizontal or 58v pp including the vertical pulse.

I don't see where you got "should be 35." Is that a typo from the input to the sync separator (which should be 35)?

You're right. I misread that part about should be 35 volts. I'm getting 75 volts peak to peak, and yes, it's the Rider's Manual. I tested my recently purchased 6SK7 tube, and it was barely good. The original was a little better, so I popped it in. The stability has improved to the point where the horizontal roll can be stopped for a longer period of time. I still have a slow and steady vertical roll though. Maybe I ought to buy another tube.