Sony Trinitron CRT CSYNC compatibility

[maxtherabbit]

Even on a digital display, you won't notice any problem with composite video sync if the video lines are properly shielded (like with coax cables). Visual interference from cvbs sync comes from the signal coupling into the video lines.

If you're using good cables, the only reason to go with csync is for compatibility reasons, where you have some non-consumer product that can't handle normal cvbs sync, like the Extron switchers.

Conversely, the only reason to go with NOT csync is if you have a European TV

[Guspaz]

Even on a digital display, you won't notice any problem with composite video sync if the video lines are properly shielded (like with coax cables). Visual interference from cvbs sync comes from the signal coupling into the video lines.

If you're using good cables, the only reason to go with csync is for compatibility reasons, where you have some non-consumer product that can't handle normal cvbs sync, like the Extron switchers.

Conversely, the only reason to go with NOT csync is if you have a European TV

I'd wager there are more devices expecting (and only fully supporting) cvbs sync than csync, and csync introduces the issue of 75ohm vs TTL, while cvbs sync is always 75ohm. There's also scenarios where some consoles have different pinouts in different regions, like the PAL SNES outputs +12v power on the same pin that the NTSC consoles output csync. With csync, depending on the console and cable, there's a risk of slowly frying your display/scaler with TTL or quickly frying it with +12v.

While it doesn't eliminate the need for different cables for different consoles/regions, sticking to cvbs sync eliminates this risk of frying a device because you accidentally plugged in the wrong cable. There are also plenty of consoles that output cvbs sync and not csync.

[Bassa-Bassa]

Hi guys,
I'm having the same issue,
introducing a sony kv-29fx30b in my extron crosspoint 300 csync setup.
I have an image on the TV but it's dull and very noisy.
Is there today a way to fix this?

I use retrogamingcables for input and output on the extron.
the csync line is attenuated by a 470ohm resistor.
(although it works the same way without it)

the image is awesome with a sync on luma or on composite video sync cable.

I'd like to test the box you've talked about, with the variable resistor
does anyone has a link?

hi, for anyone interested
I manage to get a perfect image on my Sony trinitron rgb TV (kv-29fx30b)
I used an Umsa from arcadeforge.
http://arcadeforge.net/UMSA:::15.html

it takes a rgbhv signal and makes it suitable for consumer grade crts.
i haven't analyzed the magic it does but I guess it certainly lowers the sync line way more than with a 470ohm res.
it may also level the other lines.

well it's not expensive and it works.

In case you're still around, can you confirm reds are reds again with that device? In my experience, there're two issues with the FE2 chassis - mildly degraded colours and brightness which particularly exposes with red turning brown/orange (so not "mild" there), and severely degraded colours with a green tint overall. The former happens with any non sync-on-CVBS RGB signal, while the latter only happens with non-attenuated TTL C-sync.

So in your case, did you solve the former or perhaps was it just the latter? Coming from the latter to the former may make it look like a "perfect image" while it really isn't.

I'm trying to find out if an off-the-shelf hardware solution is possible. So if an UMSA really solves this, it'd be great. Otherwise, I've been advised to try RGB to CVBS encoders in this thread, in case:

viewtopic.php?p=1578467#p1578467

Same problem here kv29cl11k.... have you ever find a fix for this? Ps pushing code "34" in green words service menu fix this colours problem a little.

Quick question, that TV set's service manual doesn't include that instruction (CDEC?) in the TT code list. Can it be reverted somehow? Not sure if it's safe if I just try it out.

Thks.

[Bassa-Bassa]

I'll answer myself - it indeed can be reverted and it's safe, once again this forum delivers.

Moreover, solves the reds being too dark issue greatly, to the point of displaying a very nice pic if you saturate a little bit the colours and making of these models very recommendable units. It's not an ultimate solution, mind - having to saturate a bit above normal levels (those set for CVBS RGB sources) reveals it isn't, and likely the brightest R/G/B need better degradation like this, but really, picture is generally good to great, at least with not-too-old tubes.


By the way, if anyone knows what's the equivalent setting for BE3D chassis to FE2's Cdec, I'll welcome any hint.