New to the forums here and a big follower since 2009 when I started down the path of restoring a good amount of camera tapes that have been sitting in the basement. This project has been picked up and put down many times, but I managed to collect a good amount of hardware over the years.
I have a checkerboard pattern from the S-Video output of the BVP+. I have exhausted all troubleshooting options that I could think of. If someone can provide some input, that would be fantastic.
About the artifact (y/c crosstalk I presume)
- The artifact is somewhat mild but gets very aggressive if I turn up the resolution boost at all.
- When turning the split screen knob half way, I see the checkerboard noise in the source as well as the processed picture.
- If I remove remove the BVP+ from the chain, no checkerboard pattern can be seen.
Example of the artifact below with and without the BVP+ in the chain:
Troubleshooting steps so far
- Replaced all S-Video cables with new shielded cables
- Tested each cable direct from VCR to capture device to ensure I don't receive this artifact
- Tested different capture devices (USB-Live2, Dazzle DVC100, and Diamond VC500) and received same results
- Tested on a different PC with the above capture devices (laptop)
- Replaced power source from a noise filtered APC Smart-UPS 750
- Removed IO / connector board and soldered shielded S-Video cables directly onto the Y/C in/out connectors on the BVP+ mainboard header
- Replaced -12V DC power supply with another -12V DC wall wort power supply with less ripple voltage (caps may be getting bad in the old one)
- Tested different tapes, including commercially recorded tapes, to ensure the source wasn't dubbed from the camcorder this way
- Tested these VCRs: JVC SR-W5U, JVC HR-S9900U, Panasonic AG-1980 and all results are the same
- Reproduced the issue on a flat screen (no capture devices)
- Replaced all electrolytic capacitors on BVP+ mainboard
I also have a TBC-1000 and Prime Image TBC Freeze II that I put each in the chain and taken out during troubleshooting. It's interesting that the Freeze II can "catch" the crosstalk when using the freeze function. I also used this TBC to produce a clean S-Video source of a frozen image that I could play with.
I think that covers what all I've done thus far. I really want to use the S-Video connectors as you can imagine how bad the quality was when I tested with composite. To mask this artifact, I attempted to use dotcrawl.vcf, but it seems to loose some sharpness and it has trouble with high motion scenes. Ultimately, I think solving this issue would be better than masking it, which in turn causes more artifacts in my opinion.
Well that was anything but concise. Let me know if anyone has seen this proc amp plagued with this Y/C crosstalk before.
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Last edited by MattTronics; 5th Feb 2017 at 21:51. Reason: Added 'replaced caps' to Troubleshooting
composite usually causes this pattern in some devices or equipment. are you going from
vcr_out_[composite] to [composite]_in_BVP_out_[svideo] to capture equipment ?
if the composite from the vcr is the main cause, then it will probably transfer through the svideo that way, or else it could be your BVP having a problem with your vcr's composite signal.
otherwise, based on what you stated earlier, it appears that your BVP is the cause and is probably faulty on the s-video input or output port. I have the exact same issue as you but with a hauppauge hvr-950Q usb2 capture card on the composite port. but anything going through the s-video port is clean. no BVP. just a capture card. this is the first time i heard of this issue on the BVP. maybe its a unique case. may want to consider finding another one cheap on ebay.
the other possibility might be that the BVP has a poor composite-to-svideo conversion and there is nothing to correct it on the BVP device side.
I'm going from vcr_out_[svideo] to [svideo_in_BVP_out_[svideo] to capture equipment since I wanted to maintain S-Video throughout the entire chain.
Good to know that going from composite to S-Video would cause this, though I never tried switching from one output to another (since I read that both are active on the BVP). One thing to note is that I am using regular VHS tapes and not SVHS; however, I don't believe that is the cause.
I did try to bypass the BVP's composite to s-video circuitry just to see if the noise somehow bled over. I discovered that header H001 has the Y/C pinouts as follows and soldered cables right to it just out of curiosity.
^^Facing the knobs
[1 2 3 4 5 6 7 8 9 10]
[11 12 13 14 15 16 17 18 19 20]
1. Luma Output
2. Chroma Output
4. Chroma Input
5. Luma Input
11. Ground (Y and C)
I agree, I think at this point it may be worth finding another unit. Replacing all those caps was a lot of fruitless labor, but it was fun .
I'll also add 'tweaking the pots' on the troubleshooting list. Didn't have any visual effect aside from the one blue pot that controlled the scan line to the right.
hopefully you will find a really cheap one to test, just in case this was always an issue but that no one noticed it, or else they attributed it to noise and used editing/filtering to remove all this time.
I'm experiencing the same. I purchased my BVP-4+ from Tom Grant, and he replied to my question with:
That doesn't sound like a problem with the BVP-4+ since it doesn't use any digital techniques in processing the image. If there's a problem with the BVP-4+ it would give a weak or muddy picture. The checkerboard pattern you describe would be produced by a piece of equipment that's involved in digitizing. So it's probably something to do with the capture device or the TBC.
Red is the highest wavelength frequency and the BVP-4+ might be passing a more vivid picture than the SignVideo proc amp (my backup), which might explain the difference between the two process amps. Also the BVP-4+ allows much wider luminance adjustments than the SignVideo, these can also cause problems in the capture chain if they're adjusted the wrong way.
So to test the BVP-4+, go directly to a TV set from your BVP-4+ (without the TBC or capture card). If the picture looks good on the TV, then it would be something in the digitizing process that's acting up with the red color.
Last edited by The Vista Group®; 18th Apr 2021 at 22:16. Reason: removed underline