What causes VCR garbled signal?

The_Outsider · #1 05-03-2021, 04:51 PM

My JVC VCR started doing this after working fine. I'm going to take it to the shop, but I'm curious if anyone knows what's causing it? It's not just the tape, which plays fine elsewhere. All tapes are doing this. It's not the outputs, because it plays miniDV fine.

latreche34 · #2 05-03-2021, 08:18 PM

What connections are you using for the test?

The_Outsider · #3 05-04-2021, 06:58 AM

I used S-Video and composite, same result on each. The miniDV side played flawlessly through both. The same tape played fine in a different machine; other tapes in this machine look the same as this one.

hodgey · #4 05-04-2021, 10:03 AM

That looks like some electronics issue, maybe with the TBC/Digital part of the VHS side. Does turning off the TBC make a difference?

The_Outsider · #5 05-04-2021, 10:35 AM

Turning of the various settings in the vcr for TBC etc. didn't help. Could the head be misaligned or something? I don't know what that would look like though, so I'm just guessing.

latreche34 · #6 05-04-2021, 08:28 PM

Could be one of those chroma clock quartz in the chroma demodulator, Looks like chroma is out of phase and no luma signal.

The_Outsider · #7 05-09-2021, 05:02 PM

Shop said some components had come loose from the circuit boards, so they soldered them back down, and it was working fine.

I brought it home, hooked it up ... and it's only playing in black and white from the VHS deck. DV plays color fine. Guess it's going back to the shop.

latreche34 · #8 05-09-2021, 05:27 PM

Ask them to check the chroma circuit capacitors and make sure to re-flow the solder joints of the quartz clock and any chips in the chroma section.