CurtPalme.com Home Theater Forum

ScionxB2k11 · Joined: 24 Jul 2011 Posts: 14

Hi All,

I have been reading this board alot since I got my first 1252q sony crt a couple months ago. I also just bought a 1270q for $26.00 off of ebay and locally picked it up here in Minneapolis, MN. I removed the each of the lens and looked at the tubes, I can't see much wear on the green and red tubes and the blue tube has light wear... So at this point I am considering it a great deal.. However this is my problem... Everything starts up just fine and runs well... however I get this strange gray/ light black line right down the center of the screen. It is only really visible when on white or watching a movie and the sky is light blue. It is there all the time but you only notice it in certaing scenes in a movie.... I looked at the tubes and I can't see any wear like what I see on the screen when the projector is running. Has anyone come across this before? I have tried searching the forums but haven't really come across what I am experiencing. I can take a picture of it and upload it later(possible in the next half hour).

Also when I got the projector It was setup for ceiling display and I had to change the polarity to get it for floor mount, I changed the switches the manual says to and it worked fine. Lastly when looking at the Red and blue tubes when projector is on and I am displaying my HTPC at 1980x1080i 30hz or 72hz, there are lines along the side of the tubes(you don't see them on the screen) but they form an L going from left to right looking into the tubes. is that normal as well.

Thanks

**Curt Palme** · Posted: Fri Aug 12, 2011 2:47 pm Post subject:

I can't say I've seen the first problem, but I would try swapping the two large top boards between your two sets and see if the problem switches sets.

Teh second line on the sides of the tubes- try using the 'blanking' control to see if you can crop them out.

ScionxB2k11 · Joined: 24 Jul 2011 Posts: 14

sry for not responding earier, but thanks for the help. I will try those suggestions. I can get the top boards off by using the service manuals instruction correct?

MrCRTing · Joined: 03 Feb 2008 Posts: 35 Location: Brighton UK

ScionxB2k11 · Joined: 24 Jul 2011 Posts: 14

Thanks for the input, I did switch out the two top boards and the 1270 still shows the line down the middle of the sreen. And it is only on green, well ast least I know its the green that is causing the line. I have a high quality vga to BNC cable going to a sony switcher, could that be the cause? But it shows up even it I select a input with nothing connected to it. I hope that makes sense.

**Curt Palme** · Posted: Wed Aug 17, 2011 2:03 am Post subject:

Sorry, this is one issue that I've never seen before. It would seem to be limited to anything that controls the green circuit though (DOH, that's probably obvious! Smile

)

It could indeed be a video issue, what it more or less eliminates is anything common to all three tubes, as in HV power supply, LV power supply, etc.

I'd start swapping the video boards. RGB input boards, the ones under the metal covers, the video/Svideo board as well.

You're sure it isn't tube burn in? Sometimes weird static images/patterns are projected just long enough to burn the tube, not enough wear to show if you're looking through the lenses, but usually you can see any wear by taking the lenses off. The color tinting also helps mask any light wear.

If not, I'd suspect something in the video circuit.

Note that the video driver boards, under the top metal cover behind the CRT sockets are different between the 1252 and 1270 I believe. There's one black connector that will have nowhere to plug into, but I think swapping the boards from the 1252 into the 1270 will work, but not the other way around. I Could be wrong on that, but you won't blow anything up if you try.

ScionxB2k11 · Joined: 24 Jul 2011 Posts: 14

ok thanks, I will try that tomorrow then. I will swap the video boards from the 1252 to the 1270. As I have not put the 1252 back together yet( meaning I haven't hooked it all up. I am hoping it is just a board problem and nothing else. I am just glad I have 2 CRT's in the same family to easily try this stuff.

ScionxB2k11 · Joined: 24 Jul 2011 Posts: 14

oh I did take all the lenses off and I could see anything on the green tube like the center line, but if the swapping the boards don't work I will take the lens off and take a much closer look and HD picture with my camera to view if I am missing anything.

ScionxB2k11 · Joined: 24 Jul 2011 Posts: 14

Well I tried the swap and it wouldn't power up at all... Then I put it back the way it was except for using the S-Video board from the 1252. I can now see the lines much better when doing zone adjustments, but the center line is still there. I will take the lenses off tomorrow and take pictures and post them. Then I will power it up and do the same, with taking pictures. Thanks all for the help.

ScionxB2k11 · Joined: 24 Jul 2011 Posts: 14

an update. Well I reset everything back to factory settings and made sure the image was as centered in the raser as I could and I guess the line just up and dsappeared like a ... in the wind. So I am happy. Thanks for the help!

**Curt Palme** · Posted: Mon Aug 22, 2011 2:20 am Post subject:

Thanks for following up, that's good to know. Never ran across that before, so I'll attempt to memorize it in my aging brain.