My "new" 1954 CTC2B 21CT55 21" roundie

[miniman82]

Ditto on the mega doorknob, mine got hot and leaked a bunch of wax but thankfully didn't take out the flyback. I shut it off and let it cool down and it never happened again, but I don't trust it. Gotta get a new one at some point.

[walterbeers]

I know which doorknob cap your talking about, and I felt it, and it seemed to be cool, at least after 15 minutes or so, and ran my HV probe around the back side of it, and no arcs between the metal frame and back side of the capacitor. Although, I still wonder if it could be leaky causing the problems. I have a CRT booster in which I can make extension cables out of it, and also an octal socket for the yoke, provided it handles the higher horizontal voltages going to the yoke. Convergence with the sub chassis removed should give me enough room to hook it up. My problem right now is finding a long enough HV wire with connectors in order to hook up the CRT with insulated plugs or sockets that won't arc to something close, or produce corona. I found HV lead wire on e-bay, but I need something to insulate the connections. The one end I can stick in a wire, in tape it and it probably would be fine. The other has to plug onto an exposed pin coming off the wire that goes straight to the CRT. I need to find something in which I can solder a terminal onto and plug into the wire going to the CRT, and have some kind of a sleeve to go over it that will insulate the connection. I also have the possibility of getting a color test jig in a couple of weeks. Doubt if it will work on the CTC2B, but maybe it will have some HV, or yoke connectors that I can use. Even if I could hook up the high voltage and yoke to it, at least it should give me an image, (although not converged) I could work with it to start with..

[Electronic M]

I'd just stick the plug end of the HV in a glass jar.....It is what I did when I needed to make a HV extension when working on my CTC-4.

[walterbeers]

Well, here is the latest as of Tuesday Nov. 3rd, 2015. I actually have a picture, color, sound and everything one would expect. Yes, I have had several problems getting there and still have problems to work out. All capacitors have been changed with caps from Capacitor World, with correct values. I did not re-stuff the cans, however I left the cans in there for appearance, and since most of the capacitors are so much smaller, there was plenty of room to mount them underneath. The big filter cans, I mounted smaller size ones on top, and I intend to put insulating sleeves over them to make it look close to original. I had to replace the horizontal output tube 6CD5 as it was weak, the vertical output tube as it showed weak on my checker, and when I got it one of the 3A2 Rectifiers was broken, so I changed all 3. Also one of the 12BH7's showed a short on my checker, so it was also changed with a NOS. I added a 5.1 ohm 25 watt resistor in series with the B+, and at my line voltage I have 405 volts, as the Sams calls for 400 volts, so I figure it's pretty close. I changed all of the white peaking coils, with values as close as possible, (most were right on), as half of them were open. I also had to change the big 2500pf 30KV doorknob capacitor as the one that was in there would arc and go off like a fire cracker. (oh yes, when it arced one time, it shorted the video detector diode 1N60 which I had to change). I now have 24KV at the second anode although the Sams says to set it at 25KV. HV won't adjust any higher. I was able to hook it up with a long piece of HV anode wire, an octal yoke extension, and used a booster as an extender for the CRT, although I patched the filament in directly eliminating the boost, as I didn't was to increase the filament voltage to the CRT. After powering it up on the bench without the CRT connected, I set the chassis on top of the cabinet, hooking everything up, even a speaker. I monitored the horizontal output current and it is running around 205ma. I had a raster, way off purity, but no big deal. I then hooked up a converter box to the antenna terminals and put the set on channel 4. I had a picture, not good, way off convergence, purity etc, but I was so happy, I actually had a picture. Of course I had to adjust the purity and center convergence. But then the next hurdle, I had no color. Checked with my scope for 3.58 osc. waveform and there was none. Started checking voltages, and the ones around the oscillator seemed to be within range, except for the color killer. I then concluded that probably the crystal was bad. Ordered a NOS crystal, soldered it in underneath, and I had 3.58 MHz waveform, but still no color. Got checking further, and found R211 12.5K 10 watt resistor open. Replaced it, and presto I had color, although sometimes the color was out of lock. I found that the crystal though needed to have it's case grounded like the original, so found a way to ground it, and now I have full tint range, and reasonable color. CRT looks good, and shows good emission on my Beltron checker. The next hurdle was that the picture was snowy, like watching a distant analog station. Found the 3.3 meg resistor on top of the tuner that supplies the RF agc was also open. Replaced it. Well, No snow! Oh yes, earlier in the restoration, I had to change the focus control and associated resistors. I had to compromise a bit on some of the values, but the focus looks good, and is adjusted to the center of the control. The next hurdle I haven't figured out quite yet. When I increase the contrast and or brightness the picture goes out of focus and pulls in from the sides, mainly the left side of the picture. I am still wondering if I could still have a bad horizontal output, damper, regulator, or horiz oscillator tube. It seems as if the beam current really pulls down the HV at higher brightness, causing the picture to narrow. That is where I'm at right now. Of course the cabinet needs to be touched up and or refinished, and I have decided I will not pull the 21AXP22 out, as I don't want to risk either breaking it, or it going to air. The top is the worst and it can be sanded and refinished with no problem as it comes off. I know of a guy that does woodworking and I might have him figure out what would be best to do, and do some work on it. Of course the trim, glass, pencil door, etc. all have to be cleaned up and polished. Here are some more pictures and screen shots. Oh yes, I was able to make a yoke cover out of a fairly solid Tupperware lid, cutting a hole through the center, and mounting the rings on it, gluing it all in place with silicon seal.

[Phil Nelson]

Originally Posted by walterbeers

I actually have a picture, color, sound and everything one would expect.

Wahoo! I hope you did a little victory dance around the workshop when you saw the first color picture.

Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html

[Electronic M]

Nice work!

[Titan1a]

Good show! Kudos!

[Username1]

Pretty cool ! ! Nice work !

.

[kvflyer]

That looks excellent! I would bet it would never have come out of a service shop with it working that well.

Congratulations are in order!

[Steve D.]

Walter,

Congratulations on a first rate job.

-Steve D.

[walterbeers]

Well, there still is a lot of work to do. I still have the width problem when brightness and contrast is increased, and my 25 watt 5.1ohm resistor that I am using in the B+ to drop the excess voltage, (since I used silicon rectifiers to replace the selenium's), gets so hot that it actually smells a bit. I may have to go to 2 separate resistors as I am afraid that the excess heat will cause it to open up. Then there is taking out the glass and cleaning up the cabinet, pencil box, and making it look "new" again. However I still want it to look original as possible. Hope I can get the cabinet looking nice, but had to get the set operating first. I may order a new damper, HV regulator, another horizontal output tube, and horiz oscillator tubes to see if that takes care of the width/ focus problem at higher brightness. Of course once I get the chassis mounted back into the cabinet, then I will try to set the purity and convergence as close as possible. There is a metal plate that the chassis sits on top of, and I hope to maybe mount it underneath somehow so if I need to work on the circuits from the underside that I don't have to pull the entire chassis. Any old retro TVs are an on going project, always hoping to improve upon it.

[ohohyodafarted]

Nice Job Walter,

RE: your issue with contrast and brightness. My CT55 does the same thing. I have never been able to figure out what causes this issue. Someone told me that the HV section is probably just not capable of supplying enough current when you drive the tube real hard. My set has a NOS flyback so I know that the flyback is not the issue.

I would bet that if you look at the HV level when you drive the tube real hard to the point where the picture pulls in, you will see the HV droping. I can drive mine so hard that I can cause the picture to almost fade away. My 21AX was rebuilt by Hawkey before they closed so it has very strong emission from the guns which easily can overwhelm the HV section.

I also have another issue that I never was able to track down. It takes about 15 minutes for the convergence to stabilize. I thought the problem was a leaky capacitor in the convergence chassis, but after rebuilding it, I still had the issue. I can speed up the stabilization by turning the brightness up real far and forcing the picture to shrink in and go out of focus. I don't understand the relationship between these issues, but after the set warms up it has a great picture.

[MRX37]

That is looking awesome, Walter.

Glad to see it up and running.

[BigDavesTV]

Looks great, congratulations! So nice to see one of these old classics displaying a nice picture again.

[technicolor]

Originally Posted by walterbeers

Well, here is the latest as of Tuesday Nov. 3rd, 2015. I actually have a picture, color, sound and everything one would expect. Yes, I have had several problems getting there and still have problems to work out. All capacitors have been changed with caps from Capacitor World, with correct values. I did not re-stuff the cans, however I left the cans in there for appearance, and since most of the capacitors are so much smaller, there was plenty of room to mount them underneath. The big filter cans, I mounted smaller size ones on top, and I intend to put insulating sleeves over them to make it look close to original. I had to replace the horizontal output tube 6CD5 as it was weak, the vertical output tube as it showed weak on my checker, and when I got it one of the 3A2 Rectifiers was broken, so I changed all 3. Also one of the 12BH7's showed a short on my checker, so it was also changed with a NOS. I added a 5.1 ohm 25 watt resistor in series with the B+, and at my line voltage I have 405 volts, as the Sams calls for 400 volts, so I figure it's pretty close. I changed all of the white peaking coils, with values as close as possible, (most were right on), as half of them were open. I also had to change the big 2500pf 30KV doorknob capacitor as the one that was in there would arc and go off like a fire cracker. (oh yes, when it arced one time, it shorted the video detector diode 1N60 which I had to change). I now have 24KV at the second anode although the Sams says to set it at 25KV. HV won't adjust any higher. I was able to hook it up with a long piece of HV anode wire, an octal yoke extension, and used a booster as an extender for the CRT, although I patched the filament in directly eliminating the boost, as I didn't was to increase the filament voltage to the CRT. After powering it up on the bench without the CRT connected, I set the chassis on top of the cabinet, hooking everything up, even a speaker. I monitored the horizontal output current and it is running around 205ma. I had a raster, way off purity, but no big deal. I then hooked up a converter box to the antenna terminals and put the set on channel 4. I had a picture, not good, way off convergence, purity etc, but I was so happy, I actually had a picture. Of course I had to adjust the purity and center convergence. But then the next hurdle, I had no color. Checked with my scope for 3.58 osc. waveform and there was none. Started checking voltages, and the ones around the oscillator seemed to be within range, except for the color killer. I then concluded that probably the crystal was bad. Ordered a NOS crystal, soldered it in underneath, and I had 3.58 MHz waveform, but still no color. Got checking further, and found R211 12.5K 10 watt resistor open. Replaced it, and presto I had color, although sometimes the color was out of lock. I found that the crystal though needed to have it's case grounded like the original, so found a way to ground it, and now I have full tint range, and reasonable color. CRT looks good, and shows good emission on my Beltron checker. The next hurdle was that the picture was snowy, like watching a distant analog station. Found the 3.3 meg resistor on top of the tuner that supplies the RF agc was also open. Replaced it. Well, No snow! Oh yes, earlier in the restoration, I had to change the focus control and associated resistors. I had to compromise a bit on some of the values, but the focus looks good, and is adjusted to the center of the control. The next hurdle I haven't figured out quite yet. When I increase the contrast and or brightness the picture goes out of focus and pulls in from the sides, mainly the left side of the picture. I am still wondering if I could still have a bad horizontal output, damper, regulator, or horiz oscillator tube. It seems as if the beam current really pulls down the HV at higher brightness, causing the picture to narrow. That is where I'm at right now. Of course the cabinet needs to be touched up and or refinished, and I have decided I will not pull the 21AXP22 out, as I don't want to risk either breaking it, or it going to air. The top is the worst and it can be sanded and refinished with no problem as it comes off. I know of a guy that does woodworking and I might have him figure out what would be best to do, and do some work on it. Of course the trim, glass, pencil door, etc. all have to be cleaned up and polished. Here are some more pictures and screen shots. Oh yes, I was able to make a yoke cover out of a fairly solid Tupperware lid, cutting a hole through the center, and mounting the rings on it, gluing it all in place with silicon seal.

Glad our caps worked out for you Walter and thanks again for your repeat business. Awesome job on that set.