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 02-20-2011, 10:12 AM
DaveWM DaveWM is offline
VideoKarma Member
 
Join Date: Feb 2009
Location: Orlando FL
Posts: 5,607
CTC-16 combo

Picked this up today. Wood looks pretty good, needs a good cleaning on the metal parts. 6JE6 had a short on pin 8, CRT is weak but at least all three guns are about the same weak and it does come up so I should be able to test it out. Looks unmolested (all the screws were in the back, and the chassis topside looks good). I will do the soft startup in a bit and see how it goes. Worst case is I have a CTC16 in a termite destroyed cabinet with a good CRT that woull make an easy swap. Tube tuner with a SS power amp.
Attached Images
File Type: jpg front.jpg (31.3 KB, 180 views)
File Type: jpg back.jpg (52.0 KB, 144 views)
Reply With Quote
  #2  
Old 02-20-2011, 10:57 AM
bgk283's Avatar
bgk283 bgk283 is offline
Nipper Rules
 
Join Date: Jun 2010
Location: Long Island,N Y
Posts: 190
ctc-16 combo

Great score Dave,congratulations. I have that exact same one i picked up last year, as well as a similiar one that my parents bought when i was a kid that i fixed up. Ive got a soft spot for these things, if you need any extra parts or any questions i can help you with, feel free to get in touch.BTW, the model is called The Stockholm and its SAMS folder 818. take care Bruce
Reply With Quote
  #3  
Old 02-20-2011, 11:28 AM
DaveWM DaveWM is offline
VideoKarma Member
 
Join Date: Feb 2009
Location: Orlando FL
Posts: 5,607
roger that. I its on the variac so far so good. The chassis is super clean.
Reply With Quote
  #4  
Old 02-20-2011, 02:33 PM
DaveWM DaveWM is offline
VideoKarma Member
 
Join Date: Feb 2009
Location: Orlando FL
Posts: 5,607
1st try, got audio so at least tuner is working, HV would not come up, I stopped it when the HOT current went up to 300ma. Will be checking for drive next. a quick check of the HOT grid with a standard DMM gave -35v. Should have been more neg, but that may have been the loading of the meter. I will put a scope on it and see hot it looks. I pulled the shunt off just to make sure the HV was not getting shorted to ground.
Reply With Quote
  #5  
Old 02-20-2011, 03:05 PM
Kalamazoo-DJ's Avatar
Kalamazoo-DJ Kalamazoo-DJ is offline
VideoKarma Member
 
Join Date: Oct 2009
Location: Kalamazoo Michigan Area
Posts: 342
wow that is a nice set dave mine has been in storage I dont know when it will ever come back out
Reply With Quote
Audiokarma
  #6  
Old 02-20-2011, 03:52 PM
DaveWM DaveWM is offline
VideoKarma Member
 
Join Date: Feb 2009
Location: Orlando FL
Posts: 5,607
well, I checked the drive wave form good PP correct shape, then checked the voltage again, this time with my vtvm, hmmm does not go neg, double check with a VOM same thing, I think I was using the DMM and was seeing a +v grid not a -grid, damn digital displays. Well I smoke the DMM when I had it in resistance mode and connected to B+ argh so not sure what it is, but forsure the HOT grid has a positive bias. I let the tube cool off and, pulled the HOT and hooked up to the grid, the instant I plug in I get a surge of +vdc on that grid. It drops as the horz osc warms up. I figure the .01 coupling cap from the horz osc to the HOT is leaking. Will check that next. I just hope I can do it with out too much in the way of pulling the chassis out. Thats one thing about combo that can be a bear, all the extra wiring.
Reply With Quote
  #7  
Old 02-20-2011, 03:53 PM
miniman82's Avatar
miniman82 miniman82 is offline
First Light: 1952-2011
 
Join Date: Jun 2009
Location: Great Mills, MD
Posts: 4,159
What's pin 8 shorted to? -35 volts grid is too high, and would no doubt cause the tube to overload. My RCA manual shows -56, so something's amiss. First suspect would be a drifted 10 meg resistor (R169), which would put a more positive voltage on the grid.
__________________
Evolution...
Reply With Quote
  #8  
Old 02-20-2011, 07:27 PM
DaveWM DaveWM is offline
VideoKarma Member
 
Join Date: Feb 2009
Location: Orlando FL
Posts: 5,607
I think it maybe ok, I replaced the coupling cap, will reinstall in the set and try again. Prelim check on the bench looks good (cat current around 200ma). I am having some arcing from the HV rectifier filament leads to the cage, insulation breakdown, I will see if I can just dress them away for now and give it another try.
Reply With Quote
  #9  
Old 02-20-2011, 10:20 PM
DaveWM DaveWM is offline
VideoKarma Member
 
Join Date: Feb 2009
Location: Orlando FL
Posts: 5,607
this thing must have been some tv shop's tube dumping ground, 12 hard shorted tubes, evey pcb effected (even the tuner had a shorted tube) mostly off brand tubes (not orig rca's).

I am pretty sure I have all of them. there are one or two questionable looking caps some dipped caps that look like they have gotten very hot at some point, one sits right next to a power restor. The resistors look different from what I have seen on a lot of sets, they seem like they have a courser appearence, some of them are very hard to read, the color bands have degraded, not sure if its from heat or just age (I think when new they prob did not look all that great), but they all test very well.
Reply With Quote
  #10  
Old 02-20-2011, 11:00 PM
ctc17 ctc17 is offline
VideoKarma Member
 
Join Date: Jul 2009
Posts: 1,615
I have seen several shorted tubes in sets that sat unused for years. I wonder if its whiskers? Can whiskers form in a vacuum?
I have had good luck banging the tubes on the table or blowing the shorts open with B+ voltage. They never seem to reshort.
Reply With Quote
Audiokarma
  #11  
Old 02-21-2011, 07:33 AM
DaveWM DaveWM is offline
VideoKarma Member
 
Join Date: Feb 2009
Location: Orlando FL
Posts: 5,607
I remembered you exp with fixing the shorts, was trying that as well, no luck.
Reply With Quote
  #12  
Old 02-21-2011, 09:33 AM
old_coot88 old_coot88 is offline
VideoKarma Member
 
Join Date: Sep 2009
Posts: 2,541
Aw man, we sold a number of that exact model combo 'back in the day'. Seeing the pics makes it seem just like yesterday.
Trusting y'all already know about reflowing the two ground stakes on the far right end of the chroma board. They go open and kill the heaters on the 6GU7's.
Bill(oc)
Reply With Quote
  #13  
Old 02-21-2011, 10:09 AM
DaveWM DaveWM is offline
VideoKarma Member
 
Join Date: Feb 2009
Location: Orlando FL
Posts: 5,607
thanks for the heads up old coot, I will def do it.
Reply With Quote
  #14  
Old 02-21-2011, 04:13 PM
holmesuser01's Avatar
holmesuser01 holmesuser01 is offline
VideoKarma Member
 
Join Date: Jul 2005
Location: Asheville NC
Posts: 1,731
Dave.... Dave.... Dave....

If you keep finding all the good stuff, there will be nothing left for the rest of us... Just kidding...

One of my neighbors has this same set in the basement. I've been trying to get it for years. Her dead husband bought it, so it's not going anywhere. I've gently reminded her kids that I would restore the TV if they ever decide to let go of it.
Reply With Quote
  #15  
Old 02-21-2011, 04:44 PM
bgk283's Avatar
bgk283 bgk283 is offline
Nipper Rules
 
Join Date: Jun 2010
Location: Long Island,N Y
Posts: 190
ctc-16 combo

When i picked this up last year and removed the CRT for cataract repair, it was without a doubt the easiest removal i ever thought possible, the safety glass literally stayed on the floor when i lifted the tube. I hope you have fun with this Dave...
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 11:03 AM.



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