Videokarma.org

Go Back   Videokarma.org TV - Video - Vintage Television & Radio Forums > Early Color Television

We appreciate your help

in keeping this site going.
Reply
 
Thread Tools Display Modes
  #1  
Old 03-09-2013, 08:48 PM
Zenith6S321's Avatar
Zenith6S321 Zenith6S321 is offline
VideoKarma Member
 
Join Date: Aug 2010
Location: Charleston, West Virginia
Posts: 303
21CT55 #2628 restoration

I'm finally beginning the restoration of my RCA 21CT55. I had intended to begin it about three years ago after I restored some vintage test equipment. Then I ran across Phil's excellent restoration web site. Then I found the Early Television Foundation site and realized my set was kinda rare. I had always thought it was special, but I had no history of early color TV development to know how few were made and that it was based on the CT100 CTC-2. Then I found Videokarma and learned how much I did NOT know about restoring old TVs. The depth and breadth of the knowledge of the members is a treasure. SteveK sent me a copy of the 21CT55 RCA Service Clinic document that is very helpful. I then decided that instead of starting with the 21CT55, I would warm-up with early B/W sets that I was extremely happy to find were actually available. I studied all of Bob Andersen's YouTube restoration videos and learned a lot. So I hunted, bought, and restored a RCA 721TS, a Dumont RA-103, and a RCA 630TS. I mixed those restorations with a Zenith 6S321 Stars-and-Stripes radio that I have used since the 60's, a 1931 Philco Model 90, 1928 Atwater Kent Model 49, and a 1924 Atwater Kent Model 20 radio. As I learned, I picked up additional test equipment along the way. Here is a picture of my restorations arranged in my living room with my 21CT55 waiting patiently. And a few pictures of the 21CT55. Its time has come.

Dave
Attached Images
File Type: jpg 100_2320.jpg (57.1 KB, 303 views)
File Type: jpg 100_0941.jpg (41.9 KB, 165 views)
File Type: jpg 100_0640.jpg (88.9 KB, 291 views)
File Type: jpg 100_2312.jpg (64.2 KB, 222 views)
File Type: jpg 100_2314.jpg (84.9 KB, 248 views)
Reply With Quote
  #2  
Old 03-09-2013, 09:59 PM
miniman82's Avatar
miniman82 miniman82 is offline
First Light: 1952-2011
 
Join Date: Jun 2009
Location: Great Mills, MD
Posts: 4,159
Heh, looks like the HV cap in your blew at some point. Interesting way to make the repair, with them all arranged in a circle like that laced with dope.
__________________
Evolution...
Reply With Quote
  #3  
Old 03-10-2013, 07:57 AM
Sandy G's Avatar
Sandy G Sandy G is offline
Spiteful Old Cuss
 
Join Date: May 2003
Location: Rogersville, Tennessee
Posts: 9,571
Can't wait to see the "Glorious Lollipop Color"....(grin)
__________________
Benevolent Despot
Reply With Quote
  #4  
Old 03-10-2013, 05:53 PM
Zenith6S321's Avatar
Zenith6S321 Zenith6S321 is offline
VideoKarma Member
 
Join Date: Aug 2010
Location: Charleston, West Virginia
Posts: 303
Quote:
Originally Posted by miniman82 View Post
Heh, looks like the HV cap in your blew at some point. Interesting way to make the repair, with them all arranged in a circle like that laced with dope.
I was college kid at the time (1974) and could not afford the right part. It functioned ok, but had a lot of corona, hence the slathered on corona dope. I hope to find a better replacement, but I have not started searching yet.

Dave
Reply With Quote
  #5  
Old 03-10-2013, 06:22 PM
ohohyodafarted's Avatar
ohohyodafarted ohohyodafarted is offline
Bob Galanter
 
Join Date: Sep 2005
Location: Whitefish Bay, Wi (Milwaukee)
Posts: 1,053
The original gray 30KV doorknob on my CT55 also went bad. I found a suitable 40KV doorknob on ebay. Mounting was slightly different, but was easily modified to work like the original. I also see that the discharging assembly that grounds the doorknob has been removed. I installed a low RPM cooling fan on the HV cage to keep the flyback cool.

Here is a link to the restoration pages of my CT55 on my web site.

http://antiquetvguy.com/Web%20Pages/...CA-21CT55.html

Good luck and welcome to the CT55 club!
__________________
Vacuum tubes are used in Wisconsin to help heat your house.

New Web Site under developement
ME http://AntiqueTvGuy.com
Reply With Quote
Audiokarma
  #6  
Old 03-10-2013, 06:22 PM
Zenith6S321's Avatar
Zenith6S321 Zenith6S321 is offline
VideoKarma Member
 
Join Date: Aug 2010
Location: Charleston, West Virginia
Posts: 303
I bought this set from the service manager at Electronic Specialty Company in Charleston, WV in 1974. My dad worked there as the accountant and I worked there a couple of summers during college. The service manager told my dad that the set was originally purchased by a doctor at West Virginia University through Electronic Specialty Co. They maintained it over the years and when it blew a flyback after the CRT had been replaced the service manager got hold of it when they bought a new set. He replaced the flyback, but had not completed the rewiring. The selenium rectifiers had been replaced with diodes before I got it. I bought it for the $75 from the service manager who had lost interest in the project. I found the 30KV capacitor shorted, so the first thing I did was fix that and a couple bad filter caps. That got the set working but it did not see much use. The CRT is a 21AXP22A dated 1957. My CR-70 shows its got emissions in the good range, so I am hoping I will not see purple in the neck when I get HV to it.

It also has a few of the white peaking coils that Nick found were bad in his, so I expect to be replacing mine.

Dave
Reply With Quote
  #7  
Old 03-10-2013, 06:35 PM
Zenith6S321's Avatar
Zenith6S321 Zenith6S321 is offline
VideoKarma Member
 
Join Date: Aug 2010
Location: Charleston, West Virginia
Posts: 303
Thanks for the link Bob! All advice is very welcome. I have the shorting bar along with others bits and pieces. When I got the set it had a chipped brightness knob, was missing the fine tuning knob, the volume knob, and the channel number insert. Here is a picture of the knobs I have, and another of a new brightness knob, a knob that I think is the correct volume knob, a fine tuning knob that I hope to modify to work, and an original "spare" peaking coil the service manager said I would probably need.

Dave
Attached Images
File Type: jpg 100_2306.jpg (63.5 KB, 73 views)
File Type: jpg 100_2308.jpg (82.6 KB, 88 views)
Reply With Quote
  #8  
Old 03-10-2013, 06:48 PM
Zenith6S321's Avatar
Zenith6S321 Zenith6S321 is offline
VideoKarma Member
 
Join Date: Aug 2010
Location: Charleston, West Virginia
Posts: 303
Quote:
Originally Posted by ohohyodafarted View Post
The original gray 30KV doorknob on my CT55 also went bad. I found a suitable 40KV doorknob on ebay.
Bob, thanks for the ebay tip for a capacitor. Would a 2700pF 40KV work ok as a replacement for the 2500pF 30KV?

Dave

Last edited by Zenith6S321; 03-10-2013 at 07:07 PM.
Reply With Quote
  #9  
Old 03-12-2013, 07:46 PM
Zenith6S321's Avatar
Zenith6S321 Zenith6S321 is offline
VideoKarma Member
 
Join Date: Aug 2010
Location: Charleston, West Virginia
Posts: 303
I've done some cleaning to the chassis. I used naval jelly (thanks bandersen) for the cleaning and to treat the rusted areas. The chassis "before" picture is above, here are some "after" pictures. Also is a picture of HV capacitors that I will replace with the 40KV 2700pF door knob capacitor to replace the mess. I have not yet figured out how to clean the HV cage, any suggestions? I compared my flyback with the two Bob shows in his restoration page: http://antiquetvguy.com/Web%20Pages/...CA-21CT55.html
I think mine is the same replacement Bob is using.

Dave
Attached Images
File Type: jpg 100_2301.jpg (73.3 KB, 109 views)
File Type: jpg 100_2328.jpg (64.3 KB, 97 views)
File Type: jpg 100_2332.jpg (92.2 KB, 107 views)
File Type: jpg 100_2338.jpg (111.8 KB, 110 views)
File Type: jpg 100_2342.jpg (122.7 KB, 150 views)
Reply With Quote
  #10  
Old 03-12-2013, 09:58 PM
ohohyodafarted's Avatar
ohohyodafarted ohohyodafarted is offline
Bob Galanter
 
Join Date: Sep 2005
Location: Whitefish Bay, Wi (Milwaukee)
Posts: 1,053
Looks like the photo of the fine tuning knob in the picture (if that is what it is) is wrong. That fine tuning knob is probably for a ctc5. You need a fine tuning knob like a CT100 uses. IF has a great big hole in the center (about 1.25" dia)

RE: HV cage. If you have an electroplating shop that does tin plate, I would take it there. Zinc can also be done but it doesn't look as good as tin plate.

Otherwise a simple paint job with aluminum spray paint looks OK.
__________________
Vacuum tubes are used in Wisconsin to help heat your house.

New Web Site under developement
ME http://AntiqueTvGuy.com
Reply With Quote
Audiokarma
  #11  
Old 03-13-2013, 06:43 PM
Zenith6S321's Avatar
Zenith6S321 Zenith6S321 is offline
VideoKarma Member
 
Join Date: Aug 2010
Location: Charleston, West Virginia
Posts: 303
Quote:
Originally Posted by ohohyodafarted View Post
Looks like the photo of the fine tuning knob in the picture (if that is what it is) is wrong. That fine tuning knob is probably for a ctc5. You need a fine tuning knob like a CT100 uses. IF has a great big hole in the center (about 1.25" dia).
Yes, I have not been able to find one, so I bought this one in hopes of fabricating a stronger central part and attaching it to the outer part of this one. The channel changing knob will fit within the outer grip area of this fine tuning knob.

Dave
Reply With Quote
  #12  
Old 03-13-2013, 07:26 PM
miniman82's Avatar
miniman82 miniman82 is offline
First Light: 1952-2011
 
Join Date: Jun 2009
Location: Great Mills, MD
Posts: 4,159
Quote:
Originally Posted by Zenith6S321 View Post
I think mine is the same replacement Bob is using.
Mine also looks like his replacement, but I'm unsure if it's just that the wax melted off Bob's donut or there actually was a different one. I always figured it was original.
__________________
Evolution...
Reply With Quote
  #13  
Old 03-13-2013, 08:48 PM
Zenith6S321's Avatar
Zenith6S321 Zenith6S321 is offline
VideoKarma Member
 
Join Date: Aug 2010
Location: Charleston, West Virginia
Posts: 303
Quote:
Originally Posted by miniman82 View Post
Mine also looks like his replacement, but I'm unsure if it's just that the wax melted off Bob's donut or there actually was a different one. I always figured it was original.
I was judging from the wider looking HV donut on his replacement flyback and its brightly colored lead insulators. Or maybe the old one discolored its leads when it died. Here is a shot of some numbers on one end of my flyback.
Attached Images
File Type: jpg 100_2350.jpg (69.5 KB, 98 views)
Reply With Quote
  #14  
Old 03-24-2013, 06:24 PM
Zenith6S321's Avatar
Zenith6S321 Zenith6S321 is offline
VideoKarma Member
 
Join Date: Aug 2010
Location: Charleston, West Virginia
Posts: 303
All of the original chassis mount caps tested open, leaky, or way off value. The "modern" (1977-ish) replacements that I had tacked in, way back then, all reformed nicely. I am not going to trust them, so I have started re-stuffing the old electrolytic caps with 105C caps. Here are some pictures of a few of them being re-stuffed. I have all but one of the chassis mount cans re-stuffed and I have started wiring them in. The 2700 pF door knob capacitor arrived and I think it will fit in the HV cage well.
Attached Images
File Type: jpg 100_2366.jpg (100.2 KB, 78 views)
File Type: jpg 100_2374.jpg (99.0 KB, 84 views)
File Type: jpg 100_2380.jpg (95.3 KB, 87 views)
File Type: jpg 100_2381.jpg (88.8 KB, 89 views)
File Type: jpg 100_2384.jpg (106.5 KB, 117 views)
Reply With Quote
  #15  
Old 04-07-2013, 04:49 PM
ohohyodafarted's Avatar
ohohyodafarted ohohyodafarted is offline
Bob Galanter
 
Join Date: Sep 2005
Location: Whitefish Bay, Wi (Milwaukee)
Posts: 1,053
Nice job on the re-stuffing!

I also use the same method, removing the can from the chassis and pealing back the rolled edge of the can to remove the tab ring. I much prefer this method over the method that cuts through the aluminum can above the base of the can. It's a lot more work using this method, but this method retains the original can in one piece, pretty much un-molested. And when re-installed on the chassis, it is hard to detect that it was re-stuffed.
__________________
Vacuum tubes are used in Wisconsin to help heat your house.

New Web Site under developement
ME http://AntiqueTvGuy.com
Reply With Quote
Audiokarma
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 10:32 AM.



Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
©Copyright 2012 VideoKarma.org, All rights reserved.