CurtPalme.com Home Theater Forum

Adz CRT Mania · Joined: 24 Mar 2009 Posts: 22 Location: United Kingdom

Hi i was wondering if anyone knew why i would be getting a bad signal to my green tube, i have tested using sa-vhs cable a 5 bnc to vega cable from my htpc and all seem to have the same problem with the green. I have looked inside and found nothing loose or problematic. The test patterns work fine which leads me to think something maybe wrong with my set up any idea's would be much appreciated.

Cheers

**AnalogRocks** · Posted: Tue Mar 24, 2009 3:14 pm Post subject:

What source are you using? I've seen this with VHS a whole bunch especialy tapes that were recorded in SLP, is seems the D50 is ver sensitive to poor video quality and on mine it makes the green tube flash.

**Curt Palme** · Posted: Tue Mar 24, 2009 3:16 pm Post subject:

Can you post a link to a youtube video clip? If the internal test patterns are OK, then I'd suspect the A board in the set (video input board). I can repair or replace it.

BTW, what is an sa-vhs? I'm assuming you mean SVGA output from a computer? If so, try switching the R and G cables, and see if the red starts to flash. Could also be a bad cable or a bad video card in the HTPC.

Adz CRT Mania · Joined: 24 Mar 2009 Posts: 22 Location: United Kingdom

I'm using a standard dvd player through s-video and a htpc through 5 bnc. I have the same problem with both connections which seem to be strange. I will try swaping the red and green connections round tonight to see if it is the cable. I will also post a video on you tube later to show you all the problem.

Adz CRT Mania · Joined: 24 Mar 2009 Posts: 22 Location: United Kingdom

Hi this is my projector running a standard DVD through a s-video cable.

http://www.youtube.com/watch?v=VtuUSpPaHRc

**Curt Palme** · Posted: Thu Mar 26, 2009 12:31 pm Post subject:

NOrmally I'd like to see what's happening on the screen, but in this case I can see the problem clearly.

I don't think it's hte tube. I think it's something in the signal going to the green tube.

A couple of things to try:

There is a thin black wire that goes to a small metal connector on the CRT socket/video amp. That's the main video signal coming from the A board. Swap those between tubes (either blue or red) and see if the problem moves to the other tube. If so, you have problems on the A board most likely.

Remove the green CRT socket/video amp. and move it to the blue tube. THere's not enough cable length to move the signal wires, so disconnect them and use the blue utbe wires on the green socket. You'll probably need to reroute the green tube thick red wire (focus) slightly for it to reach.

Leave the blue CRT socket disconnected, and put nothing on the green tube. See if the flashing moves to the blue tube.

Let me know.

Adz CRT Mania · Joined: 24 Mar 2009 Posts: 22 Location: United Kingdom

Do you know where i could get the service manual for a d50

Adz CRT Mania · Joined: 24 Mar 2009 Posts: 22 Location: United Kingdom

I have switch the video signal of the green to the red tube and it works fine, do you think it could be the tube?
Cheers

Adz CRT Mania · Joined: 24 Mar 2009 Posts: 22 Location: United Kingdom

After swapping the boards around and finding there was no problem, i tried cleaning the connections and replacing the board this has worked great and the problem has gone. Thanks alot for your help.