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 04-20-2007, 09:13 AM
jhalphen's Avatar
jhalphen jhalphen is offline
VideoKarma Member
 
Join Date: Feb 2007
Location: Paris, France
Posts: 350
Help Please! with an RCA CTC-9A

Good day to All,

I am seeking help for my French friend Wilfrid who is trying to restore an RCA CTC-9A color TV to working order. I will translate & pass on to him the infos.

The TV is complete, not recapped. Caps were sample tested with an ESR meter and appear to be in quite good condition. The set was brought up on a variac and produces a raster and some sort of video. We have the complete SAMS manual and a full set of spare tubes. H out 6DQ5 was replaced as the original tube was severely gassy.

In the 2 pictures shown here, the RCA is fed from the Aurora converter outputting monochrome 525/30 via a Steren 203-103 NTSC VHF Modulator.

My first question is: Could it be that the RCA is unhappy receiving a signal with no color burst ? i've asked Wilfrid to play a DVD in 525/30/3.58 MHz through the modulator to see if we get color. Will post results.

In the meantime, Thanks! in advance for any help/suggestions.

Best Regards

jhalphen
Attached Images
File Type: jpg RCA CTC-9 Premières Images-02.jpg (51.4 KB, 44 views)
File Type: jpg rca couleur vue dos capot ouvert 01.jpg (61.9 KB, 45 views)

Last edited by jhalphen; 03-13-2009 at 07:05 AM.
Reply With Quote
  #2  
Old 04-20-2007, 11:27 AM
Don Lindsly Don Lindsly is offline
Ex-Philco
 
Join Date: Jul 2005
Location: Colorado
Posts: 450
That TV will play fine on a black and white NTSC signal. From your picture I suggest setting up the color bias controls for grey scale and trying the AGC to increase contrast. If that does not make a significant improvement, then some troubleshooting is in order. Check chroma driver tubes as well.
Reply With Quote
  #3  
Old 04-20-2007, 12:58 PM
andy's Avatar
andy andy is offline
VideoKarma Member
 
Join Date: Jul 2002
Location: Austin, TX
Posts: 3,933
Be sure to replace any paper caps in the set, including the ones in black plastic. It looks like there's a vertical linearity problem (probably bad caps, or resistors).

The snowy low contrast picture could be caused by an open coil at the antenna input to the tuner. TVs from this era usually have two long thin plastic coils in the tuner which are there to match the 300 ohm balanced antenna input to the tuner's 75 ohm unbalanced input. They often go open when lightning hits the antenna. I've seen 2 or 3 sets with this problem. They aren't too hard to rewind if you have to.

Finally, as soneone else said, try going through the gray scale adjustment. Even with no signal, you can adjust that properly.
Reply With Quote
  #4  
Old 04-20-2007, 04:10 PM
oldtvman's Avatar
oldtvman oldtvman is offline
Larry Melton (oldtvman)
 
Join Date: Jan 2005
Location: Mishawaka, Indiana
Posts: 716
The basics first

Before assuming any type of color problem always make sure the purity and gran scale are correct. Turn down both blue and green screens and background controls and them set the purity to a pure red screen. Then bring the other color up to achieve gray scale. The other problem with those sets are burnt resistors in the screen circuits and leaky caps. Then can mask the problem and have you chasing your tail. After setting the bascis, check all screen voltages on the crt and make sure they are correct. If the crt is good the problems should be resolved
__________________
[IMG]
Reply With Quote
  #5  
Old 04-20-2007, 04:10 PM
oldtvman's Avatar
oldtvman oldtvman is offline
Larry Melton (oldtvman)
 
Join Date: Jan 2005
Location: Mishawaka, Indiana
Posts: 716
The picture on my avatar is on a ctc 9
__________________
[IMG]
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 02:47 PM.



Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
©Copyright 2012 VideoKarma.org, All rights reserved.