Color Fluctuations with some VCRs attached to Panny units??

I've seen this before. Its technical name is differential phase error, and its marked by skin tones fluctuating from just too pink to just too green every half second or so. Under 1% or so is acceptable, and equipment normally does not behave this way on its own (see below). If you can see it, the DFE is likely 5% or more. Since NTSC hue is determined by phase shift from a reference burst, something that modulates this will present itself as shifting color hue. You would need a vectorscope to really see this, but while using one even very low values of DFE can be seen.


The few times I've seen it have been in consumer gear and was due to inter-chassis interference. IOW, when two pieces of gear are within a few inches of each other, sometimes when one is on one channel and the other on another, the sync pulses beat together causing this.


You may see it come and go, and may not realize that it does this because one or the other piece of gear is turned off or on, or a channel change occurs, causing the beat frequency to change and making things either more or less noticeable.


The permanent cure is to move the two offending pieces of equipment farther away from each other, which normally fixes it every time. Try moving one unit one shelf further away, and report back, hopefully with a success story.

potus,

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I suspected I had digital artifact problems relating to the TBC in my E80H as the artifacts were induced into the "MONITORED" signal when I wasn't even recording!


Unfortunately there is no way to turn the TBC off and I returned my E80H to Sears for a refund. It was really hard as they price matched a $533 price.


After reading more and more threads, it seems Panasonic has a continuing reliability or design problem with the E80H judging from these fluctuation complaints and hard drive problem complaints.


Panasonic is my favorite brand as of now, but it seems they always have severe problems on new technologies. I suffered this with my A320 DVD Player that had a design flaw that caused the first chapter on the 2nd layer of a disc to be skipped. They gave me no help in this issue so it was exchanged for a Pioneer DV-414. My buddies CD Player was one in the first few years of CD's life and it had design defects where the whole tracking mechanism had to be replaced. It does seem once Panasonic gets their bugs worked out, they offer very high performance for the dollar. However, I was severely disappointed by the E80H's performance and many others makers for that matter, but I'm trying again with a Pioneer DVR-510H. Picking it up tonight. Hopefully I'll have good luck with this Pioneer. The luck with the Pioneer DVR-310 wasn't good at all.


Have a good one.

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I wish I had an answer, but my earlier post refered only to problems with NTSC analog, which differential phase error is a possible artifact of. Once we get into the realm of digital, none of that likely applies. My best guess would be that there is something funky about the downsampling that could be causing this, and it could even result in DFE once the signal is back in the analog realm and being input to your DVDR. I would think this more likely than inter-chassis interference in this case.


Every HD station uses equipment that is a little different than the next, and different algorithms exist for them to do essentially the same job, which might be at the root of why this is only on one station. The particular way they do things coupled with the particular way the E80 does things (or possibly the way the equipment doing the downsampling does things) is probably why you are getting that particular result. I know that's a little more vague than helpful, but likely still the way things are.


Regarding my suggestion for true sufferers of inter-chassis interference, it is unlikely that you need to move pesky units much further apart than a foot or two. It usually happens when two components are closely stacked or on adjacent shelves. Good luck potus.

Thanks for the info...


My case is a little confusing. Although my situation IS in the "digital realm", when my DTV tuner downsamples to 480i, it MUST be converting to analog NTSC. It's meant to drive standard NTSC displays. So we are back in the analog domain. (At least for signal between tuner and E80)


One might then expect that ALL 480i coming from my tuner would exhibit this problem on the E80. In fact, MOST of it is fine. Just the one station has these fluctuations. Other NTSC sources (composite out from my miniDV cam, and from my Sony VCR) are ALSO fine. So there must be something just a little "funny" about this particular NTSC signal that is throwing the E80 for a spin... It sounds like the problem is a sensitivity of the E80 to _some_ NTSC signals....


So the next question is: is there any way I could "clean-up", or "normalize" the analog signal before feeding it to the E80? I tried one of those old "Video Stabilizers" (Macrovision removers...) but it didn't seem to make any difference. I thought about running the signal through my VCR, but I have a feeling the video outs would just be a direct pass-through...


Any ideas?