Don't think anybody has posted this before so here goes; I've captured the output of pin 79 of the TBC chip in the player, I have tried connecting this to a TV via a terminated RCA - although the TV detects an NTSC signal the picture is distorted and seems to be out of sync... Would be interesting to see if I could get a useful output from this chip directly to compare to the player stock output circuitry

See some captures from my (crappy) USB scope - yellow is the stock RCA out and blue is direct from the chip, no load or capacitors

Strange, but the D925 seems to have some particularities about sync.
I have a Pioneer VSX-1123-K as AV receiver, with an internal composite upscaler to HDMI.
I tried a CLD-S315, S310, they both working great with it.
The D925 gives this signal
If I try the D925 directly to a pal monitor, it works nice.
If I pass the D925 in a TBC (got an old Leitch DPS-575 at work) it works on the AV Receiver.

So I think I've answered my own question; the sync signal is not present on VOUT pin of IC500 so I'd either have to take the sync from pin 1 and use a sync insertion circuit to combine the video+sync... Or I think i have another method that may work which involves getting the cxd2024 to output unfiltered composite by putting it in test mode... will post back the results if i get it working

Do you have any photos of how it actually appears on TV?

No, there is little point is it's not a proper picture just a mess... The reason being (as i have now found out) is that if you look at the traces from the 'scope above it is missing the sync tip portion of the signal.. this is confirmed by the service manual - shame as it'd be nice if it was the complete signal that i could just terminate and add a new RCA in place if the old one

Bingo... Nice and easy, we just need to (carefully) lift pin 71 of CXD2024 and make it high, i've just taken the 5V from the leg of the cap next to it... I now have the D/A converted composite video passed straight through via the CXD2024 comb filter (but with no Y/C separation)... We can use the rest of the existing circuit in the player but now the Y out of the S-Video is actually composite video! I'm going to de-solder the old S-Video socket and replace it with a good quality RCA with the Y connected to the hot pin. Interestingly the original composite output still works fine, in colour, I guess that's because of the other RGB chips

I'll post some A/B comparisons once i've got it all tidied up.

Before (top) and after (bottom) composite video test signal from the pioneer reference disc...



Much less noise, and in watching on the TV all the infamous 925 digital noise is gone, picture looks slightly softer

I think the reason players kept the digital processing is that while it adds the digitized look and associated noise is does sharpen the picture and at the time the seller benefit was aa sharper picture. I have a Philips CDV-488 that allows you to turn on or off the digital processing. You can see the difference when switching between the digital playback picture while viewing. Sharpens the picture but with side effects.

Yes, I was thinking the same... otherwise what would be the point of adding all the extra circuitry...

Interestingly I was doing some comparisons of my CLD-1450 (with NTSC mod) and the CLD-D925 both playing the 1st side of the CAV criterion pulp fiction disk and both players are pretty much equal in terms of picture quality... I'd actually go as far as to say that the 1450 may have more potential with simple upgrades, it has a decent power linear power supply for one vs the switching crap in the 925 and others...

The 925's color burst level is very low after the mod, which seems a bit odd. I'm not sure where to go from here with the 925 though, and a self-respecting NTSC decoder will bring the colors back up based off the burst level.

It's a pity the TBC output isn't usable (even if sync was there, there's something weird going on with the top bits of it) - the x06 versions of this player have sync on the TBC output and it looks nice. (Not sure if the earlier x04/CLD-59 has it, I should try sometime!)

The color burst signal looks great to me, looks more controlled and natural to me. All it does is keep the color decode frequency matched to the video signal it is processing. Also the cleaner the actual color signal for the picture the better the color reproduction. As long as the unit can detect the frequency the level does not matter as the frequency determines the color.

I've yet to watch a full film on it, it has an issue where sometimes after going to side B it throws an F5 error... I can get it working again by putting it in test mode and moving the slider back and fourth so i think it might be one of the position switches... this issue was present before i did the mod but i just having figured out how to fix it! I could live with it being a single sided player if anyone knows of a way to stop the player from automatically switching sides ?

It's probably side B alignment. Since you have the test disk* you should be able to align it. Even if you don't have the 925 service manual you can use the 504's one for the not-PAL bits.

I forget which M-holder the 925 has, it might be the really bad VNL16xx one.

(* - ... and the PAL GGV is unobtanium. (If anyone does have a copy please PM me so I can get it to someone in Europe who can RF capture it!)
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Also thinking about it you're right Kurtis - in fact when (not if) the comb filter gets it wrong it would boost edges etc and that would explain a lot of the 925's picture quality issues... it's a pity that there are basically no good PAL/NTSC combo players except for modded players, and maybe the DVL's.

Thinking about it, there aren't any LD players I know of that really brought out what PAL LD's could do.

I did think that but after the pickup returns to side a the unit will just show F5 or no disk even after a few power cycles, if i press the side b button before it's tried to read the toc then it shows F9. I empirically figured out that moving the slider about in test mode got it working again... I do have the service manual and have looked at the list of F5 symptoms but i'm not really sure how to resolve it... it is intermittent as i mentioned and only occurs once the player has attempted to play side B - sometimes it's fine

I definitely must try this. There might be also a cleaner way to do this. TST already goes high during vertical sync for pal signal (any one know reason for this?) according to service manual. If signal controlling this would forced high earlier, regular composite output would receive plain Y component. This way no connector modifications or adapter cables would be required.

I just bought the only copy of a belgian Pioneer service center for 52€
Seems very hard to find... I was also in touch with an italian service center who accept to sell it, I made an offer (50€) but they didn't answer me after
If you want to try to buy them I can give you the contact by PM
Here is front & back cover (already sent to update LDDB )

I Ordered my GGV1069 NTSC disc trough Pioneer Belgium some years ago. It arrived within a week. Also got one for a friend of mine.

Yep, I ordered my GGV1069 NTSC disc trough Donberg some weeks ago, arrived quickly too.
But here is the PAL disc referenced GGV1011, a "rare" catch

Sorry for kicking an old post! I was wondering if you actually tried this? If so, did you get good results?