JVC D Series Horizontal Smearing on the Composite Input

[BenM86]

Originally Posted by vol.2

Yes, it would, assuming the brightness/contrast is tracking correctly on the other inputs, and you would probably notice it if there was that big a difference.

Sorry, I didn't read your post carefully enough.

As tvnut pointed out:




So that should actually make things a little easier, assuming you have a schematic to reference.

The first thing I would check is to see if there is a video signal level in the composite video section. If that pot exists and it's set too high, I think it could cause the smearing you see to the right. Like I said, I don't know JVC, but I've seen that on other Japanese sets for sure. The service manual should have a voltage level to set it at (if it exists).

If not, then focus on the parts in the composite input circuit. Check voltages everywhere and compare against the service manual. If anything looks fishy, pull caps and check them.

Thanks! That gives me somewhere to start. I shared the service manual I have here. Based on the schematic on page 44 it looks like the composite signal goes straight into the IC, im not sure if their are any internal pots but I can get into it at some point and look.

There are over 100 adjustments that can be made via the service menu, but the service manual really isn't very descriptive on what they all actually do, outside of the standard geometry stuff unfortunately.