View Full Version : CTC-9A Getting Going Finally


kvflyer
07-07-2011, 07:22 AM
You may remember that I got an RCA CTC-9A last winter from a tip here. It was about 45 minutes from my house and boy, was it cold! It is in rather good cosmetic condition. I will start with a CRT replacement. The one in it, an RCA replacement, is about as dead as you can get. The only thing that it can supply is warmth from the heaters.

I got a CRT a few years ago, didn't even know what number it was until the guys at ARF identified it. The replacement CRT has a scratch on the face but it checks NOS. Most likely, that is the reason it was saved. I actually got it with about a dozen and a half other CRTs from a local closed repair shop. I was the only bidder on "That Auction Site".

Some time ago, I bought the odd-ball tubes that were bad and now have them all. I got new capacitors to stuff the electrolytics and that will be done prior to the first power. And that odd fuse setup that requires fuses with a bayonet end will be replaced with a new fuse holder that accepts standard fuses.

More to come with pictures...

kvflyer
07-12-2011, 06:09 PM
Last night, I took the out the first of three large electrolytic capacitors and stuffed it. Today, I stuffed the other two. I also replaced a 4 MFD @ 450 VDC capacitor that was on a board. It tested open.

Replaced the fuse holder so that it will accept the regular type of fuse instead of the odd-ball bayonet type. It is supposed to have a 3.5 Amp fuse. I put in a 3 Amp fuse because I didn't have a 3.5 Amp and it didn't blow. I consider that a good sign :)

Brought it up to 65 VAC with a variac and saw the filaments of the CRT light. Then, within the next 2 minutes, I brought it up to 117 VAC. It was drawing about 280 watts which is less than what it says on the back so I suspect nothing shorted. No stink, no smoke and I got a raster. It obviously has problems in the vertical section. The height and vertical linearity have some affect on the raster but as you can see, the linearity is way off.

All that I have done is to just clean a little and install the yoke and convergence stuff on the neck, power up.

The good sign is that I have a raster and both vertical and horizontal sweep. Don't know if I will have time right now to continue. But I wanted to get that dead 21CYP22 CRT out of it and put the "New" one in so that it didn't get broken. This is the very first round tube color that I have worked on since the 60s. Hope to get it going and watch Bonanza in Florida. I have done several black and white sets.

http://antiqueradios.com/gallery/d/146556-2/First_Power.jpg

miniman82
07-12-2011, 07:02 PM
Looks like you'll still have some recapping to do on the vert and horiz boards, but this is definitely a good start!

kvflyer
07-12-2011, 08:09 PM
Looks like you'll still have some recapping to do on the vert and horiz boards, but this is definitely a good start!

Absolutely! But that is the easy stuff. The raster makes me feel a lot better. Good flyback, yoke, horizontal is running, vertical is running. Got HV.

Since it has printed circuits for a lot of the circuitry, easy to test, easy to replace. I most likely have all of the caps. I did have to go to DigiKey to get the electrolytic caps. I wanted the correct values in a size that would fit inside of the cans. Success. I will say that the first electrolytic did test just about OK. But for how long??? It is a 1959 set and those caps are a ticking time bomb.

Mal Fuller
07-12-2011, 08:23 PM
To delete post

bgadow
07-12-2011, 10:06 PM
Very encouraging! Always a great moment, to see that raster for the first time. I can still remember the day I got my CTC-5 to wake up, after years and years of trying. What a moment!

Phil Nelson
07-12-2011, 11:04 PM
Yay! The rest should be straightforward, and probably a lot of fun, as you watch each section shape up.

I like a roundie cabinet that doesn't take up too much floor space.

Phil Nelson

kvflyer
07-13-2011, 10:01 AM
Thanks guys. My previous endeavors were a 7" electrostatic Motorola B/W, a 16" Admiral B/W Bakelite console, and an Emerson 14" B/W portable to name a few. This one will be fun to watch get better as each problem is "chipped away" at.