CTC-9 from North Hills CA
 

Hey all

well I decided to test the CRT in this set last night. I pulled the back off and to my surprise all the tubes appear to be original!! The boards are in excellent condition and no burning. They are really clean and the whole chassis looks like it has extremely low use. The flyback is pristine!! OMG this set is like new surprisingly. The CRT tested dead so I cooked it for a few on 8v with my sencore. The emission came up in the blue then the red. Green was still almost non existent. So I let it go overnight. woke up this morning to a surprise. All 3 guns on the 21CYP22 tested great! So also yesterday I checked out the chassis and looked for shorts. Pulled he horiz output tube and brought up the set slowly light bulb stayed dim. Got sound and held there with no shorts. This morning replaced the HOT and crossed my fingers. Viola. Bright vivid picture on my BK color bar and alignment tester! Nice color and the fly is staying cool. Later this week I'm going to order the lytics for the power supply. I don't trust 1959 caps.

Sounds like yours is at least as good as mine was, good stuff! Mine came up the same way, OG caps and all. Matter of fact, those were the only thing in the whole chassis I've changed, it's still on the original tube set (dates of '58).

Amazing! Now the CYP CRT is this the one with the frit seal?

All glass tubes use frit...

Lol. I know what I meant. Is this a glass and metal sealed CRT?

It's all glass, no leakage problems.

Only 21" metal one was the AXP, all others were all glass. Unless you count the leads for the gun, which I do not.

lots of pics please :yes:

I was doing some preliminary checks last night and the set went dead. Fly was not hot. No lights at all, acts like it's not plugged in, and i had no time to look into it yet. I was getting ready to pull the chassis and check HOT cathode current and write down filter cap values to order. So I will keep you guys updated. I have pics, just need to upload them.

hmmm sounds like a circuit breaker or on off swtich

No circuit breaker on this set. Just fuses. good call on the on off switch though. I will check it out tonight.

Check R193, 79 ohm cold, .49 ohm hot.

Don't have a SAMs on this one. Where is r193? This chassis is a CTC-9F

I think this is an inrush current limiter in the primary of the power transformer going to the power line. If it opens up you will lose all power into the set. I have a set which is either a CTC-9 or 10 which has this same problem...worked when first tested but then completely lost power.

:worthless

http://antiqueradio.org/art/temp/RCA...torDiagram.jpg

Freakaftr8, if you send me a PM with your email address, I can email you the complete Sams. My library lets me download 'em for free.

Phil Nelson

Well I swear pictures are coming!! I have camera issues at the moment. I did however pull back the chassis tonight and found the little inrush limiter fried off and laying on top of the video amp
Electolytic shorted maybe? All fuses check good.

It's probably just old, and fell apart. Mouser should have a replacement.

Actually think I found a close match in an old PC power supply. It's operating current is 5 amps.
And ohms at 2.5
I did a conversion and seems to me max inrush would be 67amps. I have to be doing something wrong in my calculation cause that's impossible.
Part number is 2R55A

Would this work?

think I used a CL-90 there.

opps, taking that back, prob need something that can take more current.

I have the RCA manual, and also the Sams if you like I can send them. Here's a picture of the RCA factory schematic, and a close-up of the power supply. I doubt it will show good enough detail on the main schematic, but hopefully the power supply will get you started.

That's such a great feeling to pull the back off a set and see near-virginity!!!! It's so the opposite of finding a couple of missing, tubes, and wires unhooked from the FBT, and a cluster of tubular electrolytics taped to a failed can, etc etc...

I think that set might have selenium rectifiers, but I might be off on that. The schematic looks like regular silicon diodes, but I'm not sure if there was a different symbol for seleniums back then. If it does, I'd bet they're leaking and need to be replaced with B+ diodes (and an adjusted value B+ resistor to compensate for the higher efficiency & higher raw B+ from the diodes vs. the seleniums). If they're leaking, they'd overload the B+ resistor and/or blow the a fuse.

Charles

http://i104.photobucket.com/albums/m...th_CTC9sch.jpg

http://i104.photobucket.com/albums/m.../th_CTC9ps.jpg

My CTC-9 has RCA 'tophat' diodes, those would be silicon.

Yes my set has "tophat" silicons also. Looks like they are good too.

Shawn, I remember the thermistor/current limiter was bad on the CTC-16 combo you sold to me. The wire had broken loose from one side of it. I ended up finding a "good spot" on it where I could resolder the wire (actually I think I did that on both sides), and it has been good since then. Maybe you can try a similar fix on this CTC-9.

Hey Chris

Wish I could but this Puppy literally melted. Both sides are wasted and the disc itself is destroyed. It really went.

On another note I now have my camera issue fixed and will be posting up long awaited pics tomorrow. Sorry guys for the delay.

Well I ordered a thermistor from Moyers today. Did some research and found it to be an RCAFR291 or 107291. .49 ohm hot. When I get it im installing it and checking some esr readings on the power supply. Im wondering if I cad a can short to ground. As I remember the cans all felt cool to the touch except the first one closest to the back of the set. The bottom of that can felt mildly above room temperature. Think my best bet would be to recap the set while I got the chassis out, nd do some general cleaning. As I said before the set is extremely clean and hardly any signs of heavy use at all. But dust hinders the appearance. Also, luckfully it doesn't appear to be a smokers set either. I have a bunch of pics I am going to put up and a few of the melted down thermistor.

if it has a power resistor on the lugs or sit near a big sand resistor that will make them warm as well.

Weel I recieved the thermistor today. Keep your fingers crossed for me.

Hey guys,
Well after cleaning the remnants out of the chassis from the old inrush limiter, I carefully removed the rest of the leads from the terminal strip and installed the new one.

Success! She is up and running once again!
Here are some pics and the present state in which she sits.

http://i845.photobucket.com/albums/a...9/DSC02768.jpg

Some more of the chassis after the inrush limiter crumbled apart.
http://i845.photobucket.com/albums/a...9/DSC02767.jpg
http://i845.photobucket.com/albums/a...9/DSC02766.jpg
http://i845.photobucket.com/albums/a...9/DSC02765.jpg
http://i845.photobucket.com/albums/a...9/DSC02764.jpg
http://i845.photobucket.com/albums/a...9/DSC02763.jpg
http://i845.photobucket.com/albums/a...9/DSC02762.jpg
http://i845.photobucket.com/albums/a...9/DSC02761.jpg

BTW, does anyone know how to remove the safety glass? It's quite dirty behind there..
Thanks!

wow that looks great!

That set is looking good!

As for the safety glass, you have to CAREFULLY pry the top and bottom gold trim off. The top pried straight down and bottom straight up. I like to protect the wood with blue painters tape but if you pry too hard the wood will get a dent, lay something flat under your screwdriver to spread out the pressure. The trim is also easy to distort so be careful and pry up small sections at a time until it comes loose, someone bent mine years ago but it still looks ok with only a few wavy spots. Once those pieces are removed, there will be four clips holding the glass, there are like small levers on them that you pull out. Pulling them will make the clip sort of bend in the middle but it's supposed to do that, if you look closely it will make sense how they come out. The cover of the sams has instructions too but they aren't very detailed.
I hope this helps, post a pic if you have any problems with it.

Make sure you change the horiz drive capacitor to the 6DQ5 HO. They were problem prone when the sets were fairly new. When they go bad, 6DQ5 gets red hot and ruins.

Thanks Julian, ill check it out.

Your inrush current thermister probably melted off. Its some ware around the base of the 5U4 tube.

70 ohm cold if I remember correctly.

Umm, it's a CTC-9.... :scratch2:


Mark, I didn't pry the bottom trim off mine. I just pulled the top one, then took the glass out by angling it forward and lifting it out. Saves the removal of the bottom strip, since it can be a PITA.

Yes this is a pita!! But nice and clean now! Now attacking the convergence. I must say out of all the vintage sets I own this ones the hardest to dial in!

Well I pretty much spent the night with playing with convergence coils, magnets and blue lateral. As well as purity rings. Looking good now but still not close enough. I'm trying to go for as well of a job as I gave my ctc-17 a year ago. That set in my case is perfect. This one is a lil pain but were getting close. Well as I was well into this project I noticed the vertical lin started slowly stretching out at the top. Most likely a cap going south for the winter.

All my round tube color sets do that, but I never figured out why. Maybe I'll dig into it this coming month, when I'm not so busy at work. You can see the lines start to get farther apart near the very top of the screen, but if I tweak the lin control to fix it, I come up short on height. :thumbsdn: