JVC HR-S3911U SVHS Picture cuts out
 

Anybody have any experience with a JVC HR-S3911U? It plays for about 10 seconds, then the picture fuzzes out, then it comes back. Routinely, every 10 seconds or so. It's like the tracking is screwing up.

I took the lid off and watched, nothing interesting happens to the tape when the "fuzz" occurs on the monitor. Tried different tapes, same result.

Saw one on ebay for parts that is doing the same thing, so I figured it might be a common problem.

Any of you old pros ever run into this issue or this machine (or hopefully both)?

Does it use a 60 Hz power transformer if so it may be an open filter cap.

Without knowing much more I would say on the face of things this indeed seems like a tracking issue. My JVC SVHS does the same thing, and for some reason the time code freezes as well when the picture goes too. I tried doing everything from deep head cleaning to using the dreaded "head cleaner cassettes". Neither did much good, but what did work was just letting it sit "cold" for a few weeks, unplugged and unhooked up to a TV. After 2-3 weeks of that I plugged it back in and it worked fine. No explanation for that at all besides maybe there are some internal electronics issues way above my knowledge level?

That would likely be a loss of control track issue. They use the control track 30 Hz pulses to calculate the tape time. No track pickup, no time count. Maybe tape skewing away from the correct tape path at the CTL head from a worn pinch roller, or contamination on the head?

Interesting...So then why would it work fine after sitting for a few weeks of non-use?

Also, oddly enough this would only happen with SP tapes, EP tapes played just fine, though I think in another thread someone mentioned that these VCRs had separate heads for SP and EP anyways.

SWI... Something Wrong Inside. Could be an electrical problem too.

Separate video heads. There's only one control track head.

I'd think bad lytics are probable....Especially if you can plug it in after it has sat long enough to work and not run it for a day (or however long the issue usually takes to manifest plus 20%) and after being plugged in unused it starts to act up immediately. Mechanical issues won't come back from sitting plugged in but not running.

Was thinking that too. Maybe a bad capacitor in the CTL amp circuit. I haven't run my HR-S5900U lately maybe I should give it some exercise.