View Full Version : 2 RCA tube color sets & other stuff found.


radiotvnut
11-28-2007, 05:03 PM
I went to see an older man today that used to own a TV shop years ago and he loaded me up with some stuff: An RCA Victor combo with a CTC25 chassis, a metal cabinet CTC38 set, a '78 19" Sony, a '70's 19" GTE Philco B&W, and an old B&W console of unknown make.

He said he thought the combo needed a flyback and the metal one had color problems. The chassis is loose in the combo and it's very dirty (well, they all are). No way I'm plugging these in until I do some basic checks. I know I'm junking that B&W console if anyone needs anything out of it.

That combo feels like it weighs about 4000 lbs. I do have the back. I just took it off for the picture.

freakaftr8
11-28-2007, 05:39 PM
Sweet finds!! Im envious of that combo unit!!

drh4683
11-28-2007, 07:56 PM
Nice finds. Does that combo have the 6AQ5 audio output? The early production ctc25's had the solid state audio out mounted on a large heat sink. I cant tell, but yours looks like the tube version. supposedly there were problems with reliablity while those chassis were in production and they reverted back to the 6AQ5. I have a late production ctc25 set from mid '66. Its a interesting chassis and it does not get brought up alot on the forums. Most of the time you will find a ctc-16 roundie or a ctc-31 or 38 rectangular set.

I always liked those ctc38 table sets with the tilt out control bin.

radiotvnut
11-28-2007, 09:06 PM
Bad news. The CTC38 has a bad flyback. I powered it up and the HOT runs hot and the flyback has a burnt smell as well as old wax drippings. I just left it on long enough to see what would happen. At first, the CRT checked almost dead. About 10 minutes cooking on 8 volts solved that. When I change the fly, I know I'll need to check for a proper horizontal drive signal and monitor the HOT cathode current. Is there anything else I should do to prevent possible problems? I don't know when I'll get around to fixing it. I need to fix what I've already got torn apart. But, I'm sure it's worth messing with since metal table model color tube sets seem to be rare. I didn't find that many back in the '90's when tube sets were still common.

The Sony somewhat plays. I'm sure some cleaning and adjustment will help. The GTE Philco B&W plays but the CRT is weak and it has vertical sweep issues.

Oh yes, I was going through the record compartment in the combo and found the original instruction book. The instructions on the Sony were also there. I think mine has the tube output; but, I'll double check to make sure.

Findm-Keepm
11-28-2007, 09:35 PM
Bad news. The CTC38 has a bad flyback. I powered it up and the HOT runs hot and the flyback has a burnt smell as well as old wax drippings. I just left it on long enough to see what would happen. At first, the CRT checked almost dead. About 10 minutes cooking on 8 volts solved that. When I change the fly, I know I'll need to check for a proper horizontal drive signal and monitor the HOT cathode current. Is there anything else I should do to prevent possible problems? I don't know when I'll get around to fixing it. I need to fix what I've already got torn apart. But, I'm sure it's worth messing with since metal table model color tube sets seem to be rare. I didn't find that many back in the '90's when tube sets were still common.



Two things - you're now looking for a Thordarson FLY-312 or RCA part number 119834 IIRC. There's a 119834 on eBay right now (no, not me, and I don't know/can't vouch for the seller). When you do install the new flyback, crank that efficiency coil for the proper (low) cathode current. A 0-250 mA meter (I use an analog one, bypassed with a .22uF cap) with clip leads works fine. When you finish, put a pigtail 500 mA fuse in the cathode circuit. It'll blow before the new fly cooks.

Cheers,

Chad Hauris
11-28-2007, 10:30 PM
I wonder if the flyback is completely bad in this case or just has been overloaded but still has a chance...On a CTC-16 and CTC-38 both had power supply or bad solder joint problems which caused no voltage to the horizontal oscillator. This overloaded and destroyed the 6JE6 tubes but repairing the oscillator power supply and replacing the output tube brought back proper operation.

If possible though a new flyback is the best solution along with a cathode fuse and current adjustment...have had a flyback fire in a CTC-31 which completely destroyed the flyback and HV tube socket. Don't know if this was an arcing problem, just bad flyback or output tube overload. The portable sets had either a circuit breaker in the horiz output cathode, a thermal fuse on the HO tube or both but for some reason the consoles/metal table top models never had this protection.

The easiest check for oscillator operation is to measure the negative grid voltage on the horizontal output tube. No voltage or weak voltage indicates poor or no oscillator operation.

Also I have had problems in the 6BK4 circuits cause problems in Magnavox sets where the flyback was overheating.

I have put in a fuse clip in the horizontal output cathode circuit and first put in a 6 volt fuse lamp to set the efficiency coil (minimum brightness on the lamp) then replaced the lamp with a 300 ma fuse.

radiotvnut
11-28-2007, 11:08 PM
Thanks for the information. Now, I've got something to go on when I get back on this set. I'm going to check with the local parts house and see if they by chance have a fly stuck back somewhere.

andy
11-29-2007, 01:38 AM
Can you post bigger pictures? Your pictures are always too small to see any detail. They can be as big as 900x900.

radiotvnut
11-29-2007, 01:12 PM
Here are some more pictures of the CTC25 combo.

radiotvnut
11-29-2007, 01:17 PM
Pictures of the CTC38. This set is really nasty inside!

radiotvnut
11-29-2007, 01:21 PM
And here is the Sony KV1911 "econoquick" set from '78. Were these decent sets? I sure hope it's not the one with the SG-whatever horizontal output.

radiotvnut
11-29-2007, 04:56 PM
Well, I fired up the combo and the stereo is completely dead and the TV only has it's dial lit. I found a receipt where the CRT was changed in '78. The tube checked almost dead with an H-K short on the red gun. Cooking it didn't do much good. The rejuvenate function brought the red up to about 60% and the blue and green to about 75% and also cleared the short. The label on the CRT is chewed and faded; so, I don't know who made it. There is no maker listed on the reciept. I did double check and the set does use a 6AQ5 output tube. I think a mouse made his home in this thing. Sitting these sets in a less than perfect environment didn't do them any good! I'd rather remove a set from some little old lady's living room than out an old, unheated, damp building.

andy
11-29-2007, 05:39 PM
The stereo in that combo looks a lot like the front panel of this RCA table radio.

That CTC-38 looks like it could clean up ok. Any table top RCA color set is a rare fine these days.

I see the Sony is developing a green halo. I guess it was just a matter of time. Those were good sets, but tended to have weak red and blue guns. Even 20 years ago, every late 70's Sony I got had a green picture.

Chad Hauris
11-29-2007, 08:07 PM
Weren't the Sony Trinitrons some of the last sets to use the bonded CRT faceplace (accounting for the green halo?)
I'd check the circuit breaker and degaussing thermistor on the CTC-25...have seen both of these open and cause no B+ (they are both in the input to the rectifier) Also check for bad diodes/caps in power supply.

colorfixer
11-30-2007, 01:19 AM
I was wondering about the halo on the Sony as well.

I have the same set and had to change the tube from another dead SG powered set.

The original did not have a bonded face (I popped the original tube, and it definitely didn't have a bonded face :D ).

I have a 76 vintage 12" Sony monitor/receiver which was a "hangar queen" from a transmitter site with almost no hours on it, but the raster was very green. What makes them do this? I re-did the gray scale tracking and it must have at least another 15 years of daily use on my workbench without re-occurrence.

radiotvnut
11-30-2007, 10:19 PM
The Sony may not be worth repairing after all. After playing with it, I noticed it has several problems.

1. No color (sometimes, it would pop in for a second).
2. Washed out picture.
3. faint red retrace lines even with the red G2 control turned down.
4. Some faint vertical bars on the left side of the screen.

The CRT checks about 50% on the red and green guns and about 40% on the blue. That halo looks more brown in person. It sort of looks like burnt phospher but I can't imagine what would have done it.

I do have the sams and may play with it a little more. This will probably be one I give my friend to sell at the flea market. He always needs an old set to make people turn their nose up.

radiotvnut
01-12-2009, 11:52 AM
OK, thought I'd bring this thread back to life for an update. About 30 minutes ago, a brand new RCA 119834 flyback for the CTC38 arrived in the mail. I happened to see an ad in "Antique Radio Classified" from a gentleman who was selling a bunch of old TV parts. I emailed him; and, he had the part! Now, let's see how many years it takes for me to stick it in. Actually, the TV is buried at the moment; but, at least I have the transformer on hand. BTW, the transformer has a date code of 3/84. I wonder how long RCA kept that part in production?

AUdubon5425
01-12-2009, 10:41 PM
That CTC-38 looks a lot like the 19" set my parents had - the control panel is laid out the same, but theirs was just badged "RCA" and had a two-button remote (tuning fork type) and a woodgrained plastic cabinet. I believe they received it as a wedding present which would have made it a '69 or '70 model.

radiotvnut
01-12-2009, 11:01 PM
My set appears to have been made in early '69. Later that year is when RCA went with the modern logo that's still in use.

zenith2134
01-12-2009, 11:33 PM
What ever happened to the Sony? Dead I'm sure. I think that was the one with the SG- regulator and horizontal output. I had a KV-1712 like it from '77 with a toasty CRT.

radiotvnut
01-12-2009, 11:39 PM
What ever happened to the Sony? Dead I'm sure. I think that was the one with the SG- regulator and horizontal output. I had a KV-1712 like it from '77 with a toasty CRT.

Yeah, it went to the dump because it had too many problems, including a weak tube. I would have tried to repair it had the tube been better. The old Westinghouse B&W console got trashed as well. Bad tube and too much other damage (mainly from moisture). I gave the SS 19" Philco B&W to a lady that has yard sales. I think she still has it.

Findm-Keepm
01-13-2009, 10:56 AM
OK, thought I'd bring this thread back to life for an update. About 30 minutes ago, a brand new RCA 119834 flyback for the CTC38 arrived in the mail. I happened to see an ad in "Antique Radio Classified" from a gentleman who was selling a bunch of old TV parts. I emailed him; and, he had the part! Now, let's see how many years it takes for me to stick it in. Actually, the TV is buried at the moment; but, at least I have the transformer on hand. BTW, the transformer has a date code of 3/84. I wonder how long RCA kept that part in production?

RCA sold the 119834 at least until 1988, as my RCA Distributor Price Guide shows it. They probably were working off the one last production run in 1984.

Not to sound creepy, but I need a bad 119834 - my NOS one has busted cores - otherwise ok. I'll glady pay you for your bad fly and for shipping.

Cheers,

radiotvnut
01-13-2009, 02:32 PM
RCA sold the 119834 at least until 1988, as my RCA Distributor Price Guide shows it. They probably were working off the one last production run in 1984.

Not to sound creepy, but I need a bad 119834 - my NOS one has busted cores - otherwise ok. I'll glady pay you for your bad fly and for shipping.

Cheers,

Whenever I get it out, it's yours. I don't know how long it will be as the TV is currently buried and I don't know when I'll get a chance to dig it out.

Findm-Keepm
01-13-2009, 07:48 PM
That's great! I'm still two projects behind - the CTC-38 can wait, I'll move up a recap job to fill it's place.

Thank you so much!

If you need any RCA parts for your 38, I've got a bunch......99% NOS - been collectin'....

Cheers,

radiotvnut
06-25-2009, 01:11 AM
Well, I finally cleaned up the basement and dug out the CTC38 and I'm going to try and change the flyback sometime during the next few days. I discovered that the insulation on the old one has actually become conductive. Depending on how I place the meter probes, I read anywhere between 500Kohms and 1.2 megohms. I've got a feeling that this set will need a ton of work to get it playing correctly; but, I'm going to attempt it. Tube color TV's are not getting any easier to find and steel cabinet ones are certainly not.

Now, I have a question for those that have been around more CTC38's than I have. When properly restored, will this chassis be reliable enough for daily use or should this be a set that I only turn on every so often to make sure it still works? I usually watch about two hours of TV per day (thanks RTN). I know that I'll need to keep a few hundred 6GH8's on hand, LOL!

andy
06-25-2009, 10:29 AM
000

kx250rider
06-25-2009, 11:24 AM
And here is the Sony KV1911 "econoquick" set from '78. Were these decent sets? I sure hope it's not the one with the SG-whatever horizontal output.

Good news & bad news: It only has ONE SG-613 (Hor output SCR). The power regulator is a 2SC867, if I recall. Those are fairly good sets, and usually the UHF tuner would short the 12v B+ line to ground, and cause the VHF tuner to look bad. Also they're notorious for weak CRTs, unfortunately.

Hey; is that CTC-38 a 25" or is it the weird 22" version?

Charles

radiotvnut
06-25-2009, 11:49 AM
The '38 uses a 25" (23" viewable) CRT. The Sony has already been sent to the graveyard due to excessive problems.

radiotvnut
06-26-2009, 08:01 PM
OK, if I don't cool down, there's going to be one less CTC38 in the world. The flyback replacement went fine; but, replacing the busted horizontal efficiency coil is proving to be a bitch. RCA didn't design this chassis with easy service in mind. There's 10,000 wires running around the area where the coil is soldered and none of them are long enough to move out of the way. Every time I stick my soldering iron up in there, I wind up melting some wire insulation. I have a real problem with stuff that was not meant to be easily serviced, I don't care if it's 50 years old or 5 years old! What companies need to do is hire the people that have to work on their crap to design their sets, not a bunch of bean counters. I know I'll probably catch some heat from others over what I just said; but, I've reached my boiling point!

Keefla
06-26-2009, 09:49 PM
not to derail the thread or start a war but as a dealer mechanic me and my fellow mechanics in shops/dealers/service stations all over this fine country say the same damn thing 100 times a day, take the people that work on them and have them work with the designers! things today are put togeather with no thought that eventually they will need to be repaired!!

radiotvnut
06-26-2009, 10:29 PM
not to derail the thread or start a war but as a dealer mechanic me and my fellow mechanics in shops/dealers/service stations all over this fine country say the same damn thing 100 times a day, take the people that work on them and have them work with the designers! things today are put togeather with no thought that eventually they will need to be repaired!!

Another thing that comes to mind are radios from the '20's. Many of those had the transformer, capacitors, filter chokes, etc. sealed inside a metal box with tar. I guess they thought that no one would be repairing those, either. There are some parts of my CTC38 that are fairly easy to work on; but, where I'm at right now is not one of them.

I'm just glad I had sense enough, for a change, to walk away from it before cause more damage. I still would like to get this one going, if possible.

radiotvnut
06-26-2009, 10:33 PM
One other thought. I doubt the fine folks at RCA had any idea that someone would be trying to repair one of these sets 40+ years after it was put on the market. They probably figured on it being replaced in 10, maybe 15 years. The new flyback was made in '84 and the set was built in '69; so, at least they kept parts around for a reasonable length of time. Now, companies discontinue parts almost as soon as the warranty expires.