That CTC-11...

[freakaftr8]

email sent, Thanks Phil!!

Originally Posted by Phil Nelson

You can just about guarantee that all electrolytic and paper caps in a forty or fifty year old set will be bad. If they haven't failed yet, they will soon.

It's hard to resist the temptation to power up a set immediately, but it's more prudent to replace the filter electrolytics first. Powering up on a variac offers no real protection against burning up an expensive power transformer. Yes, I have done that, and it cured me of the temptation forever.

Some old electrolytics may "reform" after a fashion, but they are not reliable to use for the long haul, in my experience.

It's also a good idea to carefully clean the HV section, as nasadowsk suggested. HV can do funny things, especially in a set where HV components are coated with carbonized cooking grease & tobacco residue. I would do this even if you are not currently experiencing Bad Things from that section.

I have a CTC-11 on the workbench and a copy of the Sams. If you send me an email by going to http://antiqueradio.org/contact.htm , we can figure out how to get you a copy.

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

[freakaftr8]

Hey Guys, here is a head scratcher...

I overlooked this the other night. In the HV cage, where there is supposed to be a 3A3 there was a 3DJ3..
The difference in these 2 tubes is that the working plate voltage of the 3A3 is 47vdc. The 3DJ3 has a working plate voltage of 25vdc. What would be the reason for someone to use the 3DJ3 HV tube and does this cause any issues with the set? The tube is still reading barely in the green if I test it as the proper 3DJ3, but testing it as a 3A3 it goes way into the questionable are, of course..

[jpdylon]

assuming the pinouts are the same, the 3DJ3 is NOT a god sub at all. Its going to have a short life trying to act like a 3A3.

Wonder who changed it out and why they used an incorrect sub....

[freakaftr8]

Im not sure but there is a slight difference in the pinouts, although they all corrospond to the proper pins the 3DJ3 has a wire from the (filiment)? coming off pins 2 and 7 going to pin 1 where the 3A3 does not..

[freakaftr8]

The other thing I noticed, there seems to be no inrush limiter in tis set anywhere, but it doesnt have a degausing field either... So maybe it's not used?

[freakaftr8]

The other thing I noticed, there seems to be no inrush limiter in tis set anywhere, but it doesnt have a degausing field either... So maybe it's not used?

[jpdylon]

The auto degaussing didn't come in until the model 16 IIRC

[freakaftr8]

Oh my bad.. you learn something new every day, still dont know why this set has no inrush limiter, but it operates.. Here's a link to a thread started by Wcarrol and a pic shows the inrush limiter there on his ctc-11, where it looks as if either mines missing or that it never had one..

it's 8 posts down on picture 3

http://www.audiokarma.org/forums/sho...ghlight=ctc-11

[jpdylon]

Could have been it was broke and rather than replacing it with the right part they just bypassed it like smart people

kinda like replacing the 3A3 with a 3DJ3

[freakaftr8]

Yikes, didnt know you could bypass these... Is that safe? I know the one on my 16 is broken, I have it held together with a shower curtan hanger! (Redkeck inginuity)!!

[jpdylon]

Its hard on the power supply tranny and caps to bypass it, not to mention the power switch!

I would get a replacement.

[freakaftr8]

Well good news on the set, we ( I ) recapped it yesterday, all filters and some throught the chassis. All lytics are swapped out, nice (i mean breathtaking raster) better than my CTC-16, deep and rich contrast and I converged and adjusted yoke and purity degauss. Then I noticed the vertical shrinking... Probably out of tolerance resistors. But I picked up a toy for me today, look in rectangular forums under maggie console, so time to work on my own set!

[jpdylon]

good to hear its coming along well. I think he should pay you for your work, or at least offer to sell it to you for less

[freakaftr8]

Yeah man seriously!! Im thinking to myself.... Dude if I am going to do the work, supply beer !!! But it's time for him to work on his own tv. Maybe ill give him help, will work for pizza, beer, money!

[freakaftr8]

What is it with the vertical circuits of these old CTC chassis, it seems that every one of them have some problem, I looked in the vertical board for some resistors that may be out of tolerance, only 2 of them are reading 10% over, now usually when they read over I juist replace them. If they read under, usually it'sbecause they are in circuit and something is drawing down the resistince. All the caps seem to be ok on an esr meter. What has happened is the Vertical height is lacking about an inch on the bottom, about 10 minutes of being on the height dramatically squishes down on the bottom, and stretches on the top but shrinks as well making my think it;s in the linearity circuit.. I did change the resistors that go from the lin and height pots to the chassis though to no avail.