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Alrighty, tonight I made some progress in inspecting this unit despite not having a service manual. In my Sony SLV-575UC manual I read how to adjust the switching pulse (same thing as Pulse generator?) against the Line out signal. Assuming all VHS machines follow a pattern, I found Video Out and SW P test points on the Toshiba so scoped them while playing a tape.
I need some help deciphering what I am seeing in the attached oscilloscope captures since I'm still figuring how NTSC video works. I tried three different tapes (1 commercial movie, 2 tapes recorded on other machines) and believe the switching point to be in the correct point compared to the diagram given in the Sony manual. However, the first two "big" pulses going from right to left are truncated compared to the diagram Sony gives. Also, I see a spike in the Video Out signal (yellow) right in line with the Switching Pulse (blue).
I'm not sure what 6.5 +/- 0.5H in the Sony is referring to. What does "H" mean in these measurements?
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