Hi all! I've appreciated the tips related to the power supply issue I've had with my 1971 RCA CTC-44A chassis console TV. I have been working with an awesome professional here in Seattle, and the PW400 board has had some sort of a big blow-out that we cannot seem to identify. Two capacitors on (Sweep Circuit) were bad and replaced, as well as a bad capacitor. No matter what else he tests, when power is turned on, amps go way up. He was thinking the high voltage transformer or yoke could be suspect (tube is not connected now to protect it). From what I've seen in previous posts here, and in the article one generous member here posted, those power issues can and seem to be elusive at times. Have any of you had anything similar happen? Of course Moyer's has all the parts, but no boards. He was thinking we could try to get a board but those are a rare item I am sure these days. Thoughts? One day last November, it just turned off. I reset it, and was OK. Happened again during another use, and then kept turning off, and got to the point where it would not power on at all (breaker tripped immediately). Had been working fine until then. Bummer! He's at a loss as to what to do, and I really don't want to lose the set.

Does your friend has a schematic for this set??

Somewhere, I have one of those "rca fix-it manuals", the little one with the "fold-out" style. I seem to recall it talking about this problem. Likely, something in the commutating ckt of the flyback or such. That cap that is "between the trace and commutating ckts" of the HV ckt was known to fail sometimes. (it is NOT an electrolytic, a polyester--film type or such.)Also--the yoke--return cap fails sometimes too. This is some type of "special foil-type", 1.5UF or such. Perhaps leaky SCR's too. Screwed--up H. drive will cause"latch-up" on the SCR's and trip the breaker too. Also--have you unloaded the HV quadrupler?? This would trip the breaker if bad--and kill the HV.

I'll see if I can find one of my manuals tomorrow. I have TWO of these sets...one in a VERY nice cabinet, and one with a not-so-nice cabinet. Both work--to some degree.

Thanks much!! I do have the RCA Field Service Guide and Sams Manual for it. I can follow up with him and see if he's checked the other items you mentioned :-) I sure appreciate it!

I FOUND my rca service guide last night. Looked at it just a bit before I went to bed. I am at work now, on a break... but I saw a few things, and ONE in particular--you need to be aware of::

The commutating cap I mentioned is C-430 I think. and RCA says NOT to check it---but REPLACE it. I recall reading this somewhere else--that this cap WILL "break down" under the horiz voltage and pulse levels--but likely test FINE on a meter. It WILL trip the breaker, and often evidently, be an "intermittent failure" taking a while to finally "fail hard". The cap is an axial one shown to be between two diodes on PW400, near the SCR sink.

And BTW---do NOT junk your 44. They are RARE. I think there are more people with CTC-5's on this site--than 44's!! You WILL "get 'er goin" again.

Thanks for your tip!! I was able to get a NOS PW400 board for it and will change it out to be on the safe side - cheaper to do that, too than get all of the components. Was also able to find a flyback at Moyers should that be bad as well. Will let you know how it goes!