Help! Sony BVM 20F1E issue.

[Andy retro]

Hello

I am hoping someone can help! I recently picked up one of these super monitors, but it seems to have an issue.

When powered on (without video source) I get faint rolling diagonal interference moving down the screen (RGB). When a video source is applied, the interference freezes, leaving some very faint diagonal lines (which can only be seen when displaying a black screen). None of it can be seen during gameplay (I use it for retro gaming) and the image quality is fantastic although good black level can vary. I have tried two different SCART to BNC adaptors and unused BVC ports are plugged with 75ohm terminators on the RGB card, but not on the other card.

I have heard people talking about reseating the boards or doing a factory reset?

Any advice would be much appreciated!

[peter_scott]

Sounds like frame flyback lines.

A photo might help.

Peter

[Andy retro]

Thanks for the reply

Yes, I’ll Get some pics up!

[will789]

Do you have any additional input boards installed? If so, which ones?

[Andy retro]

Guys, sorry about the late reply;

I cannot get photos to reproduce the intereference, but I have drawn a pic, see description at top of thread. I have also noticed black level is poor,

Originally Posted by will789

Do you have any additional input boards installed? If so, which ones?

Hi

The 21D is installed

I tried setting output to this RGB card, but the issue is still there

[will789]

Try to remove the 21d and any other additional input cards. But you MUST remove them in the correct order as the manual says otherwise it may damage them. I had a similar issue to this and it turned out to be one of the input cards causing the issue and simply removing it fixed it.

Also, I don't have my monitor with me now to test but change the sync option from internal to external if the monitor has this option (I can't remember if it does).

[Andy retro]

Do you have mean remove the 21d card completely then power on?

I reseated the two cards but no joy. Will try the deflection module tomorrow

Thanks

[will789]

Turn the monitor completely off, then remove all additional input cards (such as the BKM-21D). Keep the deflection module, analog (RGB), power modules in. Then try testing a few devices with the analog board.

[Retrotechie]

Do the symptoms change at all when the monitor has warmed up after a few hours ?
I would suspect dried up capacitors either on the scan board or PSU.
I have rarely, if ever had to re-seat boards on these monitors and have been working with them for 20 years.

[will789]

Retrotechie is most likely correct and more experienced than me. Looking back on it, I think the reason re-seating the boards fixed it for me is because the radiation shield on one of my input cards was damaged. A recap of the deflection module and video module is probably your best bet.

[Andy retro]

Originally Posted by Retrotechie

Do the symptoms change at all when the monitor has warmed up after a few hours ?
I would suspect dried up capacitors either on the scan board or PSU.
I have rarely, if ever had to re-seat boards on these monitors and have been working with them for 20 years.

No change after warm up

I reseated the boards inc deflection and no change. Sounds like you could be right about the caps