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Old 04-27-2017, 08:20 AM
brentence07 brentence07 is offline
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Join Date: Apr 2017
Posts: 7
Problem with Vertical for Philco 49-1075, Any Help?

Hi all,

I'm hoping that you can all give me a helping hand with completing my first TV restoration. I am, however, very experienced in tube radio restoration. According to some, I am having a much more difficult time with this TV than is normal, and I'm looking to see if there is someone here to can help.

The good news: I get some response out of the TV. Here's what's been done to it...
-The picture tube seems to work fine, I've aligned the magnetic ion deflector at the back of the picture tube, and replaced roughly half of the tubes (the ones that I knew were bad).
-I even replaced several mismatched tubes with the appropriate values.
-The contacts were cleaned
-All - absolutely ALL - capacitors were replaced
-The controls were cleaned
-The doorknob cap was a bit leaky and was replaced
-The candohm resistor was replaced
-The vertical output transformer was assumed to be shorted, then confirmed not shorted, but was replaced anyway.
-Injecting a signal gets sound out of the speaker
This TV chassis seems to be in tip-top shape now

The bad: I cannot get my picture on the CRT to scale the full length of the vertical. Try as I might, the picture's horizontal is good - it spans the width of the CRT. But, I cannot manage to get it to get higher than about 1/2" in either direction of the exact center of the picture tube. It creates a 1"-tall line all the way across the tube, with a distorted version of the picture for my injected signal showing within that line. A photo of this is attached.


I'm at my wit's end with this chassis, and I've spent so much time and money on it that I'd like to actually get it working. I have traced all - absolutely all - resistors in the vertical section of the chassis, and have found absolutely no problems with any of them. I still, however, get some wacky voltages on the leads of the 7N7 and 7F7 tubes, and cannot for the life of me trace why this is happening. I have also attached a full schematic of this set, with the strange voltages noted in the schematic/"V" columns of the table, and the voltages that each tube SHOULD have in the "V Original" columns of the table. These are below, in large format for easy readability..

Thank you all very much in advance for your help!

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