RCA CTC-15 (14G884M) restoration

[bandersen]

This is the other color set I picked up recently from a home in New York.



Arrival at my place.


Both have bad cataracts but CRTs test strong.


Fairly clean inside but has some hours on it. HV cover was removed but inside the cabinet. Perhaps for better ventilation?

[bandersen]

I didn't see anything that concerned me so I pulled the HO and damper tubes and did a slow power up.


After about an hour, I was up to 115 with no issues. Popped the tubes back in and after some control fiddling, got a raster!



Controls works as expected except for height. Adjusting it doesn't seem to do much and I do not have full deflection.

Hooked up a converter box and was able to pull in a pretty good image and sound. Just like the GE I had to put the fine tuning at the edge of losing the station to get sound and color.
That's good - means it's likely an issue with my signal source and not alignment.

Next up, I'll test tubes and check out the height control.

[Alex KL-1]

Great score!

[etype2]

Very nice!

[damen]

If the height control has a 150K resistor connected to it, replace it, they're always bad.

[bandersen]

Thanks. I'll be sure to check it

[Yamamaya42]

I'm even more suspicious now of the RF source being used for the source of both sets since they are showing the same symptoms, before adjusting anything I would suggest trying another RF input like i mentioned from a DVD or VCR with a different rf modulator to see if you get any better results.
also the 150K resistor suggestion can be applied to the GE as it's the same circuitry.

[old_coot88]

For the height issue, there's a small electrolytic coming off the cathode of the vert output. Also the plate load resistor of the vert oscillator (dunno if that's the 150K being referred to).

[bandersen]

Eventually, I figured out how to get the tuner unmounted.
The trick was a removing piece of plastic that covered three knobs. Veeeery careful pressure got that off then some muscle got the three knobs off
Rather nice of RCA to provide a spot to attach to the chassis.

[damen]

Yes, that plastic cover on the 15s was often broken or missing. The CTC-16 version used a metal knob cover.

[Findm-Keepm]

14-G-884MV ("Alexandria") is the full model number for the set, sans UHF. CTC15 overview: https://www.worldradiohistory.com/AR...lk/1963-07.pdf

That plastic panel is RCA 113528, should you ever need the part, and the retainers are 110468, usually 4 or 5 to a pack.

Great startup regimen! Fantastic start with color and full brightness!

Quite a bit of the CTC15 parts were married up with CTC16 parts, so if the Sams part number is MIA everywhere, look to see if it was superceded by another part number - 15/16/16X_ part numbers changed a lot back in the 60s and early 70s.

The caps near the 6AQ5 usually go leaky from the heat and proximity to the output tube. And of course, save the HO tube by replacing the cap off the plate of the 6CG7/6FQ7 oscillator that couples to the HO tube. Callback/Flyback/HOT saver.....DAMHIKT....

[zeno]

Glad to see you found the TNR mtg brackets. So nice to have.
If you like roundies next is to get a jig. So much faster & fun !
73 Zeno
LFOD !

[bandersen]

Thanks for the CTC15 link. Interesting to read about the design innovations.

I did find this curious.
They thought decreasing airflow around the flyback was a good thing?!?

[bandersen]

Flipped the set on its side to get at the chassis bolts and out it came.
Not much sign of repair. Possibly the orange drops are replacements?
Also, looks like one power diode may have been replaced.



You guys are good - 150K resistor off the height control measure over 5M!

[Yamamaya42]

Not only will you find that same 150k resistor bad in the GE, but in almost every clone of the RCA that exists.

It was bad in my Hoffman Colorcaster and my maggie T933 chassis.