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 11-01-2023, 10:03 AM
Steve D.'s Avatar
Steve D. Steve D. is offline
VideoKarma Member
 
Join Date: Sep 2002
Location: Hollywood Hills, Ca.
Posts: 1,790
RCA CT-100 No raster

My RCA CT-100 powers up and delivers good sound. The 15GP crt filaments light up and all tubes seem to light up w/o any obvious gaseous blue color. Trying not to pull the heavy chassis and hopefully something obvious that can be addressed top side with the cabinet top lid removed. Just a shot in the dark I know. Any suggestions?
__________________
Please visit my CT-100, CTC-5, vintage color tv site:
http://www.wtv-zone.com/Stevetek/

Last edited by Steve D.; 11-01-2023 at 10:14 AM.
Reply With Quote
  #2  
Old 11-01-2023, 01:26 PM
Yamamaya42's Avatar
Yamamaya42 Yamamaya42 is online now
VideoKarma Member
 
Join Date: Nov 2018
Location: Round Rock TX
Posts: 2,585
Since you have not specifically given much details other than you have sound, and all tubes seem to be lit OK, but not much other than that is known, not much to go on.
So starting with the basics, is there HV, or not, 19-20kv?
If present, then each element on the 15GP22 should be checked to see if they are within their normal ranges, this should give you some idea where to start is one or more is way off target.
__________________
=^-^=
Yasashii yoru ni hitori utau uta. Asu wa kimi to utaou. Yume no tsubasa ni notte.
いとおしい人のために
Reply With Quote
  #3  
Old 11-02-2023, 02:02 PM
Yamamaya42's Avatar
Yamamaya42 Yamamaya42 is online now
VideoKarma Member
 
Join Date: Nov 2018
Location: Round Rock TX
Posts: 2,585
I see that it has a ballast tube, could one section of it have failed and you still have IF/Sound? How often do the fail?
__________________
=^-^=
Yasashii yoru ni hitori utau uta. Asu wa kimi to utaou. Yume no tsubasa ni notte.
いとおしい人のために
Reply With Quote
  #4  
Old 11-04-2023, 06:54 PM
dtvmcdonald's Avatar
dtvmcdonald dtvmcdonald is offline
VideoKarma Member
 
Join Date: Nov 2012
Posts: 1,191
Has it worked recently?

First, remove both horizontal output and damper tubes, clean pins, and lightly coat with Deoxit, plug them back in and recheck.

If that does not help, unplug CRT socket and check all the voltages except
focus and convergence ... be VERY careful not to get anything close to those two places.

IF they are OK, if you have a good HV probe (good to 20 kV) check convergence and focus voltages. Convergence is derived from the main
19.5 kV HV supply so it checks that.

Beyond those checks it gets more equipment dependant.

I've had no raster twice: once was a filament pin that was not contacting, the other was a damper tube pin not contacting.
Reply With Quote
  #5  
Old 11-04-2023, 11:19 PM
Steve D.'s Avatar
Steve D. Steve D. is offline
VideoKarma Member
 
Join Date: Sep 2002
Location: Hollywood Hills, Ca.
Posts: 1,790
Thanks for the tips.
__________________
Please visit my CT-100, CTC-5, vintage color tv site:
http://www.wtv-zone.com/Stevetek/
Reply With Quote
Audiokarma
  #6  
Old 11-05-2023, 08:05 AM
Pio1980's Avatar
Pio1980 Pio1980 is offline
VideoKarma Member
 
Join Date: Aug 2008
Location: Angel Station, Alabama
Posts: 63
I had a 21CT55 with a bad fbt and other problems ca 60 years ago that iirc the chasselis could be accessed from underneath the assembled set. Is this one similar?
You do have operational FBT function?
__________________
Goodness comes from getting the basics right, glory is to be found in tending to the details.
Reply With Quote
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 12:52 PM.



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