Sony PVM-20L5 RGB Problems

[jdubs]

Guys, any ideas on this one?

I have a MAK Strike supergun running its SCART / RGB output to my PVM-20L5 via one of these SCART->BNC cables:

http://shmups.system11.org/viewtopic.php?f=4&t=42362

Here are two pics of the 20L5's picture with the above setup and my cps2. The first is with the "Ext Sync" button pressed and the second is without it pressed:





With the button NOT pressed, you can hear the monitor searching for sync (some sort of switching sound from inside the cabinet can be heard).

The Supergun works fine as tested with my cps2 and cps3 and Micomsoft Framemeister Mini. The PVM-20L5 works fine with its composite input as tested with my Dreamcast. BUT, RGB is driving me nuts. Its behavior is the same with my RGB modded NES and SNES.

Something else that is important to note is that I also tried running the BNC outputs from my SCART->BNC cable into an Extron SS200 sync regenerator but it didn't do anything.

Any ideas? Maybe I need an lm1881-based sync stripper?

Thanks all.

-Jim

[kamiboy]

The L5 does not need raw sync, it functions just a well being fed composite video as sync.

Looks to me like something is not wired right. It still puzzles me why people think sync stripping is this panacea for all video problems. Dont bother with sync strippers, instead look at your cables.

[Fudoh]

On my BVMs I have so switch from internal to external sync *AND* from component to RGB. Maybe you've done one but not the other ?

[kamiboy]

The colours in the second picture being correct leads me to think that the set is set to RGB rather than component.

[SePh1r0tH]

Make sure the sync mode is set to external instead of internal in the display settings, I think I had this problem at first with my BVM.

Never mind just read that you used the ext sync button, I dunno -_-

[jdubs]

The L5 does not need raw sync, it functions just a well being fed composite video as sync.

Looks to me like something is not wired right. It still puzzles me why people think sync stripping is this panacea for all video problems. Dont bother with sync strippers, instead look at your cables.

When you say composite video as sync, how should I make a cable change to accomplish that? Also, the L5, while not needing raw sync, can still use it though, correct?

Thanks,
Jim

[jdubs]

On my BVMs I have so switch from internal to external sync *AND* from component to RGB. Maybe you've done one but not the other ?

Fudoh, RGB is definitely selected as is external sync. The only time I've gotten the semblance of a picture (which is highly skewed and only momentary) is when external sync was turned off.




I've been told, over e-mail, that it may be an issue of the sync not being strong enough, which I would have hoped would be correctable by my Extron.

The behavior being exhibited leads me to believe its a sync issue....which I have no idea how to address.

-Jim

[RGB32E]

Have you verified 240p via component works fine?

[22point8]

Have you tried a factory reset? Maybe there is a sync setting thats been changed in the service menu, like sync on green being forced on or something? open menu, press enter+degauss, hold blue only/reset until it says factory, press blue only/reset again.

[jdubs]

Guys, check this out. I connected a wire from the MAK's sync output (from the screw terminal, before it gets to the SCART out) to the SCART's pin 20 (I opened up the SCART side of the SCART->BNC cable so I could get at the pins) and I have a picture....a gloriously perfect picture!!!

Any idea on how to permanently fix this, though? Do I need to change around the SCART->BNC cable's wiring? I want to use my SCART switch, too.

Wow, I am excited!

thanks!!
Jim

[kamiboy]

Never mind, looks like you found the issue.

[Fudoh]

If your supergun has a FEMALE Scart OUTPUT, the Sync wire needs to go to Pin 19, not Pin 20.

[jdubs]

Never mind, looks like you found the issue.

Yes, tried my SNES Mini (RGB-modded), which like the supergun, worked fine with my Framemeister so I know it works. Its exhibited the same behavior as the supergun.

With and without Ext Sync on:

[jdubs]

If your supergun has a FEMALE Scart OUTPUT, the Sync wire needs to go to Pin 19, not Pin 20.

I tried connecting the sync out to (I thought) pin 20 (the cable's a male).

Here's a couple of pics:

[jdubs]

If your supergun has a FEMALE Scart OUTPUT, the Sync wire needs to go to Pin 19, not Pin 20.

Fudoh, you got me thinking. I tried removing the temporary wire and then bridging pins 19 and 20.....IT WORKS! This means that the SCART->BNC cable was wired improperly and I need to remove the sync line currently going to 20 and solder it to 19 instead.

-Jim

[Fudoh]

it was wired for the wrong direction then.

[jdubs]

it was wired for the wrong direction then.

Yep, exactly right. Thanks Fudoh!!

The snes is working now, too. Wow, these monitors are insanely good.

Appreciate everyone's help in getting this problem solved!!

-Jim

[Ed Oscuro]

I thought I had a similar problem for a bit - turns out that hitting the H/V button (with ext sync on) is the way to go.

Now I have another, different issue: With EXT SYNC disabled, scanlines seem reasonably sharp but obviously it's not usable in this state (no sync).

With EXT SYNC in use, the picture is centered about right but it's a bit on the bright side and the scanlines seem a bit defocused (blurry). Reset and underscan controls don't help. Any thoughts here?

The unit's user interface controls all look perfectly good when it's used without a source plugged in. I have yet to try actual 480i / 480p sources in component.

Edit: It's been suggested that this is bloom-related from failing to try turning down the RGB pots on the back of the unit - I have yet to try that.

[Ed Oscuro]

Yep, that seems to account for it. Just the last 5-10% of the RGB pots travel accounts for the bloom and perhaps 75% of the overall quality problems. Half of the rest seems to be consistent between boards, so either the PVM is getting older / needs to be tweaked / there's something in the supergun itself. Interestingly (or maybe not) Sengoku Ace Ep 2, which is the first board I tested, puts out a different (somewhat less-well-regulated) picture than does Flame Gunner (which is on PlayStation hardware), with a faded vertical line of pixels on the left side of the picture (a bit blurred). Picture itself looks fantastic overall though. I've yet to try out component or RGB display from consoles, which will also help determine how much (if at all) the supergun itself may be adding to the quality issue.

For the moment that leaves me with one question - is there an hours count on the PVM 20L5, and if so how do you find it? I know how to get into the service menu (in the menu, press DEGAUSS and ENTER) but I don't see anything that suggests it in there. If somebody can share the service manual that's be great too (currently looking for it, but no luck so far).

[jd213]

Hi, I just got a JP21 breakout cable from Wookiewin and I'm having a similar problem as the original poster with my 20L5. I first tried contacting Wookiewin, but thought I'd ask here as well just in case.

I can only get an all-green, scrambled picture, it looks exactly like the first picture in the thread. Tried several different systems (modded DUO-R, modded AV Famicom, and JP Mega Drive), and it's the same on all of them.

The monitor (PVM-D20L5DJ) says "NO SYNC" no matter if I have the EXT SYNC button pushed or not. I double-checked all the connections, menu selections, and everything. Component and RGsB from other cables work fine, so I don't think it's the PVM. Is it possible I got a miswired breakout cable?

The cable says "RGB21 ONLY", for what it's worth. I'm sure all my system cables are correct, since they work fine with the Framemeister. Also tried rearranging the sync cable with each of the R, G, and B inputs, but no combination worked. From what I can tell, only the green cable is putting out a signal.

[Guspaz]

It sounds like you're using SCART cables for your consoles, but using a JP21 breakout cable to connect to your PVM. So that'd be the wrong breakout cable. If your consoles are using SCART cables, then you need a SCART breakout.

[jd213]

Thanks for the response, but they're definitely JP21 cables since I got them in Japan and they work with the Framemeister (using the adapter that came with it). So I guess the only answer is the breakout cable is for SCART?

[Guspaz]

That could be too. I mean, it could just be a bad breakout cable, but it really sounds like a JP21/SCART mismatch.

You could open up the breakout cable and verify how it's wired, see which one it matches: http://circuit-board.de/forum/index.php ... utze1-jpg/

[jd213]

Thanks, I tried opening the breakout cable, and it mostly seems to match the JP layout, but I'm not 100% positive since the internal wires Wookiewin used don't seem to be fully color-coded.

But... after remembering that RGsB from a PS2 worked, I was able to get a proper picture by combining the G and Sync with a BNC T-adapter, then inputting to the G input on the PVM with EXT SYNC off. I'm not sure if the picture is as good as it could be when using RGsB instead of external sync, but I don't see any problems in particular.

Not sure why the external sync isn't working as-is, could the ext sync input on the monitor be fried? L5 PVMs don't need their outputs terminated, right? And there isn't a menu option that turns external sync on, there's only the EXT SYNC button, right?

Is there something in the service menu that might help?

I wonder if I should try a breakout cable from retrogamingcables, but they no longer have the JP21 version of the breakout cable on their site. Tried contacting them about it months ago and they said it was out of stock for a few weeks and that they'd get back to me, but I still haven't heard from them so I went with Wookiewin.

[jd213]

Was finally able to get a JP 21 breakout cable when it briefly came back in stock on retrogamingcables, and it works fine, so it looks like Wookiewin's cable was indeed defective, even though he said it was tested before shipping. Sent him a replacement request last week, but still no response.

I can finally enjoy get full RGB enjoyment on my PVM, almost 6 months after buying it...

[DoomsDave]

Glad to know I'm not the only one immature enough to use POO(I sometimes use BUM too).