G07 DIM picture

andrewuts1

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I recently recapped a 19" G07 and the screen still looks very dim. You can barely see the screen unless the lights in the room are completely turned off. In the dark the picture is fine. I have recapped several chassis and have never really had this problem. I adjusted the flyback with limited change as well as the color pots.

The only thing that is unusual about this chassis is that the suction cup thing that attaches to the tube itself is loose and doesn't look like it makes a snug fit. The two little prongs are inside the tube but I believe the suction cup thing is just not pushed alll the way down on the end. Could this be causing my problem? Or is this a tube rejuevenation issue I've heard about? Thanks, Andy
 
Could be the screen control is too low... some monitors have a black level control that could be set too low (WG4600 comes to mind for that one)... Brightness is too low... Or it could just be a weak tube.

If it's a weak tube then rejuvenate it and see what you get.

Also check to make sure the B+ voltage and the drive voltages are good going to the neck board.
 
Could be a weak tube, could be a fault elsewhere - as channelmanic said, check your voltages. Cranking up the SCREEN control on the flyback should make the picture pretty bright and washed out with angled retrace lines. The G07 doesn't have a black level control. I'm leaning towards a weak tube. Do you have another G07? If so, swap the chassis into it and see if the problem follows the chassis...

The suction cup on the anode connection does not need to be tight. It's purpose is solely as an insulator, to protect and insulate the HV connection underneath. Without it, it would be too easy for things to touch or come close to the HV, causing arcing. The actual electrical connection is done with the metal tabs inside.

-Ian
 
Is rejeuvenating a tube difficult? Have no experience in this area...

No, it's not difficult, but you need a picture tube rejuvinator. If you have one, they're quite simple to use - just follow the instructions in the manual. If you don't have one, getting one to fix one tube probably isn't worth it. First, verify that it's the tube. There are other faults that can cause a dim picture. But, once you're sure it's the tube, I'd take it to a TV repair shop and have them zap it for you - shouldn't cost much, just tell them you have a weak picture tube you'd like them to test/rejuvinate. Or, see if a nearby KLOVer has one and would be willing to help.

Worst case scenario, start keeping an eye on the curb on trash day, find a 19" TV set and rob the tube out of it.

-Ian
 
First check the tube (assuming you've replaced the flyback and verified you have good neck glow).

Next - Are all the colors present? Or is red brighter than the others? You can try replacing R517. When it goes bad, it limits the 12v to the color drive transistors and makes the colors fade away...
 
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