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-   -   I have Horizontal Disease...yet again Admiral 20X1 Chassis (http://www.videokarma.org/showthread.php?t=276404)

Chris K 01-29-2024 08:37 PM

I have Horizontal Disease...yet again Admiral 20X1 Chassis
 
It worked, kinda, bringing it up slowly on original parts. Then I started on recapping the power section and replacing electrolytic caps...turned it on...still worked, maybe a bit better. Kept going replacing caps one by one, checking resistors and replacing any bad ones etc...

Full screen and raster. Cleaned all the controls. Fed in a cross hatch pattern and got junk for the horizontal. Followed the service data for dialing in the horizontal oscillator and frequency...still junk.

The oscillator waveform and frequency are perfect...exactly how they look in the service data.

https://imagizer.imageshack.com/img924/9152/FZWNAG.jpg

This is the junk I have...

https://imagizer.imageshack.com/img922/5061/JfD7AT.jpg

https://imagizer.imageshack.com/img924/7637/W7so4x.jpg

So frustrated. I see so many restorers on YT get TVs from this era working so well about halfway through testing and replacing parts. The Crosley, Dumont GE Locomotive and now this Admiral all sitting in my shop with mysterious horizontal issues I cannot solve. Mad, frustrated and feeling like I need to take a break from this hobby if I don't get some success soon. :tears::tears::tears::tears:

Chris K 01-29-2024 08:42 PM

Jesus Ch#@*t. It's my freekin' pattern generator isn't it? Holy crap...lemme check.

Chris K 01-29-2024 08:47 PM

I'm a moron.

https://imagizer.imageshack.com/img923/692/Cqgg33.jpg

Never mind. Ancient and unreliable test equipment. Lesson learned.

Alex KL-1 01-30-2024 05:44 AM

Well, sh****t happens... We all sometimes stumble upon that things. In the end, you have great news, a great working TV :banana:

Recently I posted about some experiment I'm making with a TV, http://videokarma.org/showthread.php...=1#post3255461 , only to discover after making the title, the culprit is another section :bash:
Diagnosing is about that, after all...

Chris K 01-30-2024 08:12 AM

I've had advice from some of the experts here several times to make sure the video generator is working properly with a known good TV before making a judgement on what should be addressed. I went down a lot of long and dark streets chasing non-existent problems on several TVs because of forgetting that. The faulty generator is a Sencore 48 I picked up about a year ago. It has performed well until now. I think the issue is the RF output control pot. I have a Leader VG that has always been rock solid so I guess I'll need to break that out for these tests. What I need is the Sencore VG-91. That seems to be the restoration industry standard.

old_coot88 01-30-2024 08:41 AM

Severe signal overload was first thought upon seeing that first screen shot.

Kevin Kuehn 02-08-2024 09:58 PM

Quote:

Originally Posted by Chris K (Post 3255487)
I'm a moron.

https://imagizer.imageshack.com/img923/692/Cqgg33.jpg

Never mind. Ancient and unreliable test equipment. Lesson learned.

Besides the generator, it never helps to lean the CRT up against a piece of test equipment with a huge 60 hz isolation transformer inside. After all the CRT is magnetically deflected. ;)

Electronic M 02-09-2024 01:50 AM

Quote:

Originally Posted by Kevin Kuehn (Post 3255648)
Besides the generator, it never helps to lean the CRT up against a piece of test equipment with a huge 60 hz isolation transformer inside. After all the CRT is magnetically deflected. ;)

Not to pile on but I've also seen changes in deflection setup when running sets that early on their sides....I kinda learned the hard way that if the original settings give somewhat reasonable picture with the set on its side don't try to tweak to perfection with the set on its side as the change in position relative to earths magnetic field will throw several things slightly off when turned upright....
Similarly on color sets try to have the set facing the same compass direction as you plan to store and use it in when doing scan setup and purity and convergence.

old_coot88 02-09-2024 09:10 AM

Quote:

Originally Posted by Electronic M (Post 3255650)
Similarly on color sets try to have the set facing the same compass direction as you plan to store and use it in when doing scan setup and purity and convergence.

This was a major point with pre-autodegauss sets (e.g., RCA CTC-15 and prior).

Chris K 02-10-2024 06:54 PM

Got it guys. Thank you very much!


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