BVP4+ intermittent signal issues (c/s switch?)

[bilditup1]

Hey all,

I'm almost done assembling my VCR capture setup (AG-1980 --> AVT-8710 --> BVP4+ --> AIW Radeon 9800 AGP) but have run into a problem with the BVP4+ that I just got. Initially it completely mangled the signal - made it look like attempting to tune into a very weak analog station back in the day, except much worse, with a vertical green bar moving from left to right across the screen and most of the rest of the image being black with some chroma noise. Sometimes, the signal gave up, and dropped out entirely.

At first I thought it was the cables, but that wasn't it. I removed the AVT-8710 (which I'm not even sure I need? since finding out the AG-1980 has a built-in full-field TBC? pls advise) from the signal chain, but that also changed nothing. Eventually I opened up the BVP4+ and began fiddling with the screw on the blue box on the left (which is supposed to solve overscan issues, but I figured what the heck). No dice.

Eventually, as I was about to give up, I flicked up the Analog/Digital switch on the back, and hey presto! the picture is. Full of chroma noise, but a picture nonetheless.

I then attempted to reproduce the issue by messing with the cables, switches on the back &c. Switching the relatively stiff composite/s-video input switch did it - back to the entire picture dropping out, coming in like a weak TV station, or nothing. Flicking this back and forth while putting some downward pressure on the switch eventually gets me the picture back - sometimes in color, and sometimes b/w (y, I suppose) only (messing with the herringbone filter or analog/digital switch after that seems to bring it back).

I'm guessing that this input switch is faulty or something, or maybe that the contacts are messed up. Is this something that's fixable with a DeoxIT cleaner, or do I need to have it repaired (not quite handy enough to do it myself)? If the latter - I'm gonna try and see if I can get a partial refund on this or something, since it was advertised as being in working condition.

Any other advice would be much appreciated. Thank a lot!

Update:

Quote:

Originally Posted by bilditup1

I removed the AVT-8710 (which I'm not even sure I need? since finding out the AG-1980 has a built-in full-field TBC? pls advise) from the signal chain

I've since reread the FAQ on this and understand they are different; sorry.

[lordsmurf]

Quote:

Originally Posted by bilditup1

I've since reread the FAQ on this and understand they are different; sorry.

Yep.

- AVT-8710 = external framesync TBC = clean the signal
- AG-1980 = internal line TBC = clean the image
- from http://www.digitalfaq.com/forum/vide...time-base.html

Are you still having BVP4+ problems?

[bilditup1]

One more issue - it appears that when lowering the PTP or IRE controls, the picture gets garbled into something not fully tuned - looks kind of like it loses sync. This begins at 9 o'clock for PTP and 11 o'clock for IRE. I can't imagine that this is normal, right?

ED: So yes, lordsmurf, still having problems (thread updated while I was writing this).

[lordsmurf]

Perhaps the BVP4+ is malfunctioning. Remember that you cannot raise the IRE or luma too high, as it will corrupt the signal. The BVP4+ is very powerful, and can sometimes be too powerful.

How does it look on unity? (all settings to default/0)

[bilditup1]

Quote:

Originally Posted by lordsmurf

Perhaps the BVP4+ is malfunctioning. Remember that you cannot raise the IRE or luma too high, as it will corrupt the signal. The BVP4+ is very powerful, and can sometimes be too powerful.

Yes, I don't intend to - this is only happening when I lower it below 0 to around the 9 o'clock point on PTP and 11 o'clock point on IRE. Increasing it works all the way up to max without corrupting the picture in the way I'm describing (though of course it results in unusable, blown-out garbage, lol)

Quote:

Originally Posted by lordsmurf

How does it look on unity? (all settings to default/0)

Well, I find that it makes the picture cleaner, but much darker. IOW the 'haze' of VHS is gone, but I suspect this is at the expense of detail, especially in the background of very dark scenes like in my 'test' tape (shrinkwrapped tape of Les Miserables performance). The default SMPTE bars that are output by the AVT-8710 (which I'm returning after having done more research...) look a bit off when flipping between unprocessed and processed in the split-screen. ED: Also, when using the color adjustment controls, vertical black lines show up between the color bars, along with some other artifacts that remind me of sharpening artifacts caused by turning the sharpness controls all the way up on a TV. I'm not sure how 'normal' any of this is.
Oh, and even though this is a retail tape that has not been played back before, there is significant chroma noise in the picture; according to Tom Grant, who I called earlier today, this is probably a sign of bad caps in the AG-1980. The repairs are gonna cost more than the equipment at this point

[lordsmurf]

Quote:

Originally Posted by bilditup1

The repairs are gonna cost more than the equipment at this point

The VCR was $2k new, and worth about $400+ in mint condition.
What did you pay?
If you paid only $200, and it costs another $200 to get it refreshed like new, then it's not really expensive.
Even if the total cost was about $500, it's still a bargain for a $2k deck.

[NJRoadfan]

The distortion when lowering the IRE is likely normal. Why? Because lowering the black level to 0.0 IRE can mess with the sync level. Its one reason why black is setup to 7.5 IRE in the US NTSC standard, mostly to give it some headroom. Ideally a device like the BVP4 should be used in combination with a NTSC waveform monitor and vector scope to avoid bad levels, but many times this isn't feasible.

[bilditup1]

Quote:

Originally Posted by lordsmurf

The VCR was $2k new, and worth about $400+ in mint condition.
What did you pay?
If you paid only $200, and it costs another $200 to get it refreshed like new, then it's not really expensive.
Even if the total cost was about $500, it's still a bargain for a $2k deck.

Right, this is just in for a penny, in for a pound grumbling. I paid maybe $175 for the deck. TGP's refurbishing service is $325 plus shipping to him - are you aware of others?

[lordsmurf]

Quote:

Originally Posted by bilditup1

Right, this is just in for a penny, in for a pound grumbling. I paid maybe $175 for the deck. TGP's refurbishing service is $325 plus shipping to him - are you aware of others?

Not for cheaper, and not more reliable.
He's your guy. (He's our guy now, too!)
Don't forget the coupon: http://www.tgrantphoto.com/sales/ind...talFAQ-coupons
You can DIY, but that's just not a skill we have here. We use it, not fix it.

After a repair, these things are beauties.

[bilditup1]

Quote:

Originally Posted by lordsmurf

Not for cheaper, and not more reliable.
He's your guy. (He's our guy now, too!)
Don't forget the coupon: http://www.tgrantphoto.com/sales/ind...talFAQ-coupons

Thanks!

Quote:

Originally Posted by NJRoadfan

The distortion when lowering the IRE is likely normal. Why? Because lowering the black level to 0.0 IRE can mess with the sync level. Its one reason why black is setup to 7.5 IRE in the US NTSC standard, mostly to give it some headroom. Ideally a device like the BVP4 should be used in combination with a NTSC waveform monitor and vector scope to avoid bad levels, but many times this isn't feasible.

Thanks. I think that I've since confirmed this - found a tape with some very bright content, and I could go to "-L" with PTP and and til maybe 10 o'clock with IRE. Already began badgering the guy who sold this to me on ebay about this, but looks like he's off the hook except for the issue with the finicky inputs.
Which, btw, what do people think? Just put some DeoxIT on there?

[bilditup1]

Hey guys, I (finally!) got everything up and running again. The difference post-repair is pretty stark - see these quick screenshots (compressed but the difference is obvious anyway). Although there are still some diagonal artifacts of some kind that I'm concerned about and am not sure how to deal with, the awful chroma noise I had is gone.

[bilditup1]

There are also vertical artifacts of some kind- alternating light and dark bars. I don't think they're visible in the screens though, so I'll have to make a video excerpt later...

Oh, and one more thing I forgot to mention - the AVT-8710 has been replaced in the capture chain by a DataVideo TBC-3000. Not sure if a broken one of these is capable of causing the artifacts I'm describing here.

[bilditup1]

Upon further investigation - the diagonal artifacts seem to persist even after removing both the TBC and the proc-amp from the chain. Turning off TBC, turning 'Picture' (which I think is actually 'sharpness') all the way down appears to make them slightly less prominent, they're still there. Could these be in the source video itself? Or else, what am I missing?
Also, using the histogram I found that the levels were below 16 using the BVP4+ at defaults. Using the 'extend luma black point' control got it within range but I'm not sure if that is 'best practice'. I also managed (I think?) to get levels within 16-235 using VirtualDub's controls, fwiw. Not sure how to proceed. (This particular vid is a commercial one that is available on DVD, so I don't have much reason to cap it other than gaining experience. Practice makes perfect and all.)

ED: Not sure if I should make a separate thread for this or what...

[bilditup1]

I decided to make a new thread for the diagonal gunk in the proper place, since the original issue here has been dealt with.