RCA CTC-7 Found! - Info Needed...

[classicradio]

Hello Everyone,

I'm new to this forum but I think I've brought a neat find that I'd like to share in hopes of getting some information back! I was lucky enough to stumble upon an RCA 21-CD-8865U "Anderson" with a CTC-7D chassis at a local estate this week. The elderly couple had a collection of DVD's larger than most people could hope to amass in a lifetime. Obviously they got hooked on television early with this color RCA.



Let me start off by saying that I know little about vintage TV's but I've been collecting antique radios since 1996. I've been meaning to get a vintage TV up and running before '09 and when I saw this one was an early color set, I couldn't resist!



After looking over the set, I've found some good and some bad.

The good: besides one ding in the front, the cabinet is in pretty good shape. Also, the tube, which is a 21CYP22A LF12312 looks very clean with no noticeable irregularities in the phosphors. Being that the neck is stamped with the RCA Colorama logo I wonder if it was replaced at one time. Furthermore, the chassis is very clean and besides some dust it doesn't look like it's ever seen any repairs. The serial is B8160291 and the chassis is stamped with CTC7D, 7451L1, RVP 274.

Now for the bad: someone clipped another fuse over the original fuse on the chassis, which is blown. To make matters worse, there are some drips of wax coming out of the top of the power transformer. While I haven't cleaned up the chassis or checked any of the tubes, I'm hoping that this problem is nothing more than some short and bad tubes... which is probably what sent this set into the basement in the first place. The flyback looks okay and I see no other damage... but the sky is the limit with TV problems... hence why I rarely work on them.

Which brings me to the part where I ask for some help: when exactly was this set made and how can I go about finding schematics? I see someone posted CTC-7 schematic downloads on this forum some years back but the link is now dead. Does anybody have a copy they could send me? Without schematics I think I am pretty much lost. Thanks in advance!

[jpdylon]

Great find!

Shame someone jumped the fuse. You'll want to look for a sams photofact. These pretty much give all of the service information necessary to work on them.

You can pull the leads of the power transformer and check the windings with a high resolution ohm meter to make sure the transformer is still alive. If not, there is probably someone here with a parts chassis that can help you. Hell, if I can get a power tranny for a 1963 packard bell roundie, the ctc-7 shouldn't be too hard to get

At minimum you should replace all of the main power supply electrolytic capacitors before even attempting to operate the set. A shorted cap would have caused the main fuse to blow in the first place. Also pull the chassis and remove the high voltage cage (big tall metal cage with holes in it) and look at the condition of the flyback transformer. If you see a big puddle of wax, chances are its a gonner.

The colorama is a rebuilt tube. Colorama was RCA's designation for a rebuilt tube, Hi-lite was for a brand new tube. You might want to check the CRT emission too to make sure its still usable.

If you're in the southern california area, particularly San diego county I would be glad to help you with the set. The more of these we can preserve and restore now, the better

[Eric H]

Hi, welcome to AK.
I have that exact same model, "Mr Anderson" as I call mine. it's a 1958 model.

Yours is considerably cleaner than mine!

Mine drips wax from the transformer also but the transformer works fine so I think it's just the nature of the beast, the wax is soft and it's on it's side hence it drips after 50 years.

[Sandy G]

Homina ! Homina ! Homina !

[Eric H]

Check your Private Messages, I sent you a link to the service manual.

[classicradio]

Eric, thanks for the schematic. Err... actually 50 page service manual - RCA definitely wasn't leaving techs in the dark on these sets!

Thanks Again!

P.S. Filter caps will definitely be in order before power-up. Hopefully I can check tube emissions on my Eico tube tester... it has the TV socket extension but I don't recall too many tubes being in the manual, especially color tubes. I'll be heading home from college next weekend so I will grab my tube tester and update in a week.

[zenithfan1]

WOW!! Lucky enough to find the deluxe chassis set, enjoy the beautiful technicolor picture on that thing when she's all ready to go. And also, welcome to the forum and good luck with that gorgeous set!!

[Dave A]

Do you have the screw-in legs that it should be resting on?

Dave A

[Sandy G]

Originally Posted by Dave A

Do you have the screw-in legs that it should be resting on?

Dave A

Hush, dammitt ! I was fixin' to concoct a cock'n'bull story about how there was Absolutely No Way It Could Ever Work w/o the legs, & try to big-deal him into sending it to me... Curses, Foiled Again !! (grin)

[classicradio]

Originally Posted by Dave A

Do you have the screw-in legs that it should be resting on?

Dave A

No. They weren't on or anywhere around the set when I picked it up. I didn't know it originally had legs until I spotted the sockets in my rear view mirror. I was going to return to the estate sale the following day but I had classes all afternoon - so no luck there!

I suppose I could turn some new legs on the lathe if I feel ambitious enough.

[Steve D.]

Originally Posted by classicradio

No. They weren't on or anywhere around the set when I picked it up. I didn't know it originally had legs until I spotted the sockets in my rear view mirror. I was going to return to the estate sale the following day but I had classes all afternoon - so no luck there!

I suppose I could turn some new legs on the lathe if I feel ambitious enough.

Here's a link, courtesy Ed Reitan's site, to a catalog picture of the "Anderson".

http://www.novia.net/~ereitan/Galler...nderson300.gif

Notice the legs are not very long. These brass tipped legs are available in most Home Depot type stores and can be stained any finish. There is some ventilation through the bottom of the cabinet so you might want to install legs before warming the set up.

Good luck with the restoration.
-Steve D.

[classicradio]

Originally Posted by Steve D.

Here's a link, courtesy Ed Reitan's site, to a catalog picture of the "Anderson".

http://www.novia.net/~ereitan/Galler...nderson300.gif

Notice the legs are not very long. These brass tipped legs are available in most Home Depot type stores and can be stained any finish. There is some ventilation through the bottom of the cabinet so you might want to install legs before warming the set up.

Good luck with the restoration.
-Steve D.

Home Deopt? Seriously? I never would have guessed! I will definitely check them out this weekend as well! Thanks for the tip!

[classicradio]

UPDATE:

I was finally able to power up the chassis tonight, but so far the results were not good. The previously jumped fuses were not blown and of the correct amperage, so I thought I was in the clear. I checked all of the tubes (except the picture tube) and found 9 of them were bad, many of which had shorts. After replacing all of those I replaced the two 3-section electrolytic cans and powered the unit up on the variac.

I had read on various other posts that many of you do initial power ups without the high voltage section. To me this meant disconnecting the tube and removing the 6BK4 and 3A3 tubes from the high voltage cage.

Current draw was looking good up to 90 volts where I stopped for a second - only to watch the high voltage fuse pop with a nice blue spark. I assumed the high voltage section was isolated because I left the tubes out but obviously I was wrong. Any tips? Do I need to perform a short check around the flyback or was my leaving those tubes out a bad idea? Maybe I should have yanked the 1V2 and 6BK4 as well?

Anyways this is an early indication that something is wrong. Any assistance will be greatly appreciated as this is the most complicated radio I've ever seen!

[classicradio]

Well if the cap for the 6BK4 was laying against the high voltage cage could that have caused a spark? There was no audible evidence of one.

I replaced a few suspect caps around the 3/4 amp fuse (BTW Radio Shack is the only place that stocks these anymore) and powered the set back up with the 3A3 and 6BK4 back in circuit, 6DQ5 and 6AU4 removed. One strange pop but no blown fuse up to 120V. I also got a strange knocking sound from around the high voltage cage - not the sound of a spark but more like the sound of an oscillator at around 5 Hz.

I put the set together and powered everything up on the variac. I reached 110V where I began to hear untuned station static from the speakers, and the high voltage scanning noise came up shortly thereafter. Within 10 seconds of that happening I began to hear a rush of static around the set so I powered it down. It sounded just like a sweater fresh out of the dryer if you know what I mean. Not thinking this is normal I powered the set back down but so far I can't find any problems. The flyback looks like new compared to some sets I've seen - so i don't think that is the culprit. Also, I never saw any static or picture.

Any ideas?

[Dave A]

Sandy,

I did this query only in the memory of my sainted grandmother Gertrude who was given the same set for Christmas that year by my dad and siblings.

I spent many hours up close to this set as an 8 year old with my feet under the set gathering x-rays similar to the shoe fitting viewer at my Johnson Shoes dealer that my mom brought me to trying to kill me.

Sorry for your conniving loss, but the legs live on for the sake of history and for my early interest in color tv. Still going 50 years later.

Grinning too,

Dave A