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-   -   The Ebay CTC-7 is home! (http://www.videokarma.org/showthread.php?t=261252)

StellarTV 04-13-2014 04:12 PM

Quote:

Originally Posted by Tom Albrecht (Post 3100477)
That one was way too easy...

That's what I thought... expecting a full on resto! Of course now, after running it for over a week, a few of its weak points are beginning to show through. Color oscillator first began shifting frequency intermittently, a twist of the fine tuning control to and fro would sometimes bring it back into sync. That was just a touch up of the chroma oscillator slug, been fine ever since.

Problem two, blue background pot opened up, picture looked like it was going way too blue and then way too green. Piece of cake. Had no luck finding a 700k pot, so installed a 1.5meg one shunted with a 1 watt 1.5 meg resistor. Right on the money.

Problem three, horizontal sync is becoming unstable. Gotta dig into that one today. The Sams shows some lovely black beauties inside the HV cage so I just wonder if those were ever replaced. So hope to check into that today.

Quote:

Originally Posted by IsthmusTV (Post 3100486)
Nice! I'd love to find one of those stands for my Abington which now just sits on a furniture dolly.

Oh wow, nice! We're now official Abington brothers. :D Is that the original 21CYP?

Quote:

Originally Posted by Einar72 (Post 3100669)
I guess you do know the way to San Jose. Only place I've been in Kalifornia. Nice score!

Drive was beautiful too, weather was perfect. I stayed off the main freeways most of the way and it was a windows-down sort of day.

DaveWM 04-13-2014 04:36 PM

Something to watch for on the horz instablility, If still a problem after all the usual suspects have been addressed, check the resistor across the coil that is used to adjust the horz hold. I had that one go way high, resulting in a horz that was excessively sensitive in setting. The resistor is on the board. you cant ck it in circuit since its in P with the coil, so you have to lift one leg to check.

egrand 04-13-2014 05:22 PM

Quote:

Originally Posted by DaveWM (Post 3100978)
so you have to lift one leg to check.

Just be careful you don't fall over when you got your leg in the air. :D

DaveWM 04-13-2014 06:00 PM

oh my...

:D

Electronic M 04-13-2014 06:23 PM

Quote:

Originally Posted by egrand (Post 3100982)
Just be careful you don't fall over when you got your leg in the air. :D

:lmao:

Steve D. 04-13-2014 06:32 PM

Quote:

Originally Posted by IsthmusTV (Post 3100486)
Nice! I'd love to find one of those stands for my Abington which now just sits on a furniture dolly.

You could always attach some tapered legs and get the set off the floor. Or find a 50's era table for it to sit on. Just a suggestion.

-Steve D.

StellarTV 04-13-2014 07:10 PM

The tapered legs would look great on this TV.

IsthmusTV 04-14-2014 10:27 AM

Quote:

Originally Posted by StellarTV (Post 3100974)
Oh wow, nice! We're now official Abington brothers. :D Is that the original 21CYP?

Yes it is. It's test good, with just a slightly weaker green gun.

I actually did some work on mine this weekend. I've had a nagging intermittent on the video output board that caused the luminance level to go way high. I was sure that it was the socket of the 12BY7, so I replaced it. That was not easy because the board is pretty well cooked so I had lots of problems with lifting traces, etc. And of course, that didn't solve the problem :no: I took another stab at it yesterday, and under magnification, I found a bad solder joint on one end of a resistor that had gone previously undetected (I'd been over this board countless times). I still have a minor intermittent hue shift that I need to track down, but otherwise it's playing great. Long live Abingtons!

Clark

Polaraligned 04-14-2014 04:20 PM

Nice set. I want one!!

BigDavesTV 04-16-2014 08:57 AM

That's a great looking Abington, CTC-7, the picture too! I picked up a CTC-7 Sanford, around the time you got your set, I sure hope mine will turn out with as nice a picture as yours, I now have a standard to judge by! :-) My set has the original 21CYP22, which tested dead on the red gun, and very weak on green and blue, initially. I let it warm up a while, then tried out my newly acquired Beltron on it, brought the red gun from dead to a little weak, green and blue up much more. I have the chassis out, I've got to get started on it, initially looks ok, but appears not to have been powered on in quite a long time. I'll start with power supply, and work up from there. Looks like I have many caps to replace in this chassis!

BigDavesTV 04-16-2014 09:02 AM

I forgot to add that this so far will be the oldest color set I've ever worked on! The earliest prior to this set, is two CTC-11 Chassis! They remind me a little of each other, since both chassis stand up vertically in the cabinet, but several differences beyond that. My Sanford also has factory UHF!

BigDavesTV 04-20-2014 04:25 PM

Well, I made a start on my CTC-7 Sanford chassis, yesterday! I have the older version that has the 5U4's mounted atop the power transformer. Over the years, the heat had dried out the wiring insulation between the tube sockets, and years ago some technician had spliced in some wires and I guess they worked, but looked absolutely awful. I have replaced them to tidy things up. More to do, but already I feel better! :-)

StellarTV 04-20-2014 05:53 PM

Quote:

Originally Posted by IsthmusTV (Post 3101050)

I actually did some work on mine this weekend. I've had a nagging intermittent on the video output board that caused the luminance level to go way high. I was sure that it was the socket of the 12BY7, so I replaced it. That was not easy because the board is pretty well cooked so I had lots of problems with lifting traces, etc. And of course, that didn't solve the problem :no: I took another stab at it yesterday, and under magnification, I found a bad solder joint on one end of a resistor that had gone previously undetected (I'd been over this board countless times). I still have a minor intermittent hue shift that I need to track down, but otherwise it's playing great. Long live Abingtons!

So funny... because one thing I've not mentioned yet is that the set started developing intermittent bright luminance. tapping/rocking the 12BY7 would cause the problem to get worse, so pulled the chassis. The board was pretty nuked underneath from the heat; someone had bridged several bad board traces with fine wire and slider and did a fairly decent job.

That resistor... the same one you mentioned- looked like the leg was oxidized and solder never flowed onto it properly but it took a while to find. Problem solved.

I put a socket saver between the tube and socket to keep the board from cooking any more.


Also, the horizontal instability was a dirty tuner tube socket. It was the only one that, when rocked, would have an effect on anything. It's solid for now!

Quote:

Originally Posted by BigDavesTV
Well, I made a start on my CTC-7 Sanford chassis, yesterday! I have the older version that has the 5U4's mounted atop the power transformer. Over the years, the heat had dried out the wiring insulation between the tube sockets, and years ago some technician had spliced in some wires and I guess they worked, but looked absolutely awful. I have replaced them to tidy things up. More to do, but already I feel better! :-)

Good good! Keep us informed. :yes:

Geist 04-20-2014 06:16 PM

Hi All;
I never heard of a Socket Saver, Do You have any Picture(s) ???

THANK YOU Marty

WISCOJIM 04-20-2014 07:19 PM

Quote:

Originally Posted by Geist (Post 3101695)
Hi All;
I never heard of a Socket Saver, Do You have any Picture(s) ???

THANK YOU Marty


http://www.tubesandmore.com/products/P-ST8-1000

.


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