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Old 02-07-2019, 09:34 PM
keith6996 keith6996 is offline
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Philco 48-2500 projection tv

Hello Gentlemen

Last spring I found a Philco 48-2500 at a flea market for the can't refuse price of $7 dollars. The cabinet was fair to good, but what impressed me was the set was complete. Most of the tubes were vintage philco (4 tested bad). I changed out all the caps and a handful of out of tolerance resisters.
I got some great tips from this website, especially from Tom Albecht about going to a solid state voltage Tripler which I installed and pulled the dc restoration tube. The focus became consistent and improved the picture.

The problem I have now is a light vertical bar in the middle of the picture. I can move this bar slightly to the left or right by adjusting the horizontal hold control. Could this be a horizontal phase problem ? I carefully went through the damper and horizontal circuits and changed any out of tolerance resisters, but I suspect the problem could be elsewhere.
Please check out the picture.
I would appreciate any suggestions !


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Old 02-07-2019, 10:32 PM
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Electronic M Electronic M is online now
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Looks like a drive bar...Caused by setting the horiz drive too high.
Tom C.

What I want. -->

Reading between the scan lines since the mid 2000's.
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Old 02-08-2019, 07:27 PM
keith6996 keith6996 is offline
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Unfortunately this particular set doesn't have a adjustment for the horizontal drive. I believe it's using fixed resisters. Reading a thread from Tom Albrecht, he increased his horizontal drive by adjusting the value upward of 2 resisters. I can adjust these the other way to see if this makes a difference. I'll probably pull the chassis out this
weekend to take another look. I'll keep you posted.

Keith W.
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