The CTC-9 is here!

[AUdubon5425]

I picked up that same set in a darker finish a few months ago. Yours looks ten times nicer than mine though! Great score.

And yes, my CTC-9 and 11 both have the original picture tubes, and both say "Colorama."

[Zenith26kc20]

Last night I finally finished recapping the horizontal board and ran the set up without vertival or horizontal output tubes. I had checked the electrolytics a bit ago but wanted to double check for heating. They were fine so in went the tubes and in went the chassis. It had horizontal frequency WAY off frequency when I first brought it up a while ago. I was greeted by a rock solid, in frequency picture. I still have vertical issues and a lot of adjusting (checking the HOT current for the first thing). I let it run about ten minutes and all seemed well. I'll get to the vertical next!

[Kevin Kuehn]

Congratulations. I love the all wood control panel on that set. When RCA started using the metal trim control panels, IMO it was the beginning of things starting to look cheap.

[hi_volt]

Very nice set. Drool......

[Zenith26kc20]

Started working on the Latham again the other night. After changing all the bad color tubes I decided to check /dip horizontal current. It is over 200 mils! Put the alignment tool in the waveform coil instead of linearity and promptly messed up the synchroguide peaks! Then the scope went south! Sat down and looked at the schematic and said, STUPID!
Last night brought the other scope home and realigned the synchoguide, got a great picture but still too much horizontal current! At 110 volts I can dip to 196 mils! Strange thing is the screen grid on the HOT is way to high. Around 150 volts. With high current I would think it would be low!
Any ideas?

[miniman82]

Check shunt regulator current, it may be dragging down your HV supply. If that's not it, the screen resistor may have drifted.

[Zenith26kc20]

High voltage 23 KV, screen voltage 160 volts, cathode current 201 milliamperes. Now the real problem, my Sam's Photofact is very different than the set. Screen resistors in Sam's says a 16k 4 watt with a 120k 2 watt in parallel. Mine has a 56k 2watt in parallel with the 16K. I put resistors in series with the 47 ohm to the screen grid to lower the screen to what Sam's says, and the cathode current dropped to 170 milliamperes. About 1 inch of width missing, poor focus, reduced vertical and a generally dismal picture. I reconnected everything as original and ran the set for 15 minutes. Glorious picture. After 15 minutes, shut it off and touched the flyback. Barely warm! Tried two meters for the current, analog and digital, both the same. Ohmed the screen circuits, all OK. Horizontal drive is -57 volts. The Sam's says CTC9F is in the bunch. Mine is a CTC9F. Anyone have an RCA schematic with these values?

[Zenith26kc20]

A few months ago I took the CTC-9 to Mississippi to replace the Zenith roundie for a while. It wasn't long till the 'smell of death" started to come out while it was playing. I pulled the chassis and reconnected it outside the cabinet and after a short while the smell appeared to be the power transformer. I had no time to work on it then so it sat until a few weeks ago. I got curious and pulled the B+ fuse and plugged it in. It sat with the filaments on for a while and the transformer got luke warm after about an hour. I actually forgot about it as I was working around the place and late that night I saw it lit in the dining room. The transformer was still just luke warm. Fast forward to last weekend. I brought another transformer set up to do B+ adjusted by the variac at 385 volts connected to "C2" with the B+ fuse still missing. It came right up, bright snowy screen. I hooked a converter box up to it and played it for about 9 hours. After a quick setup I was very happy with the picture!
Now I'm wondering if the set has a leaky silicon rectifer in the doubler. I did see a slight ripple in the picture awhile back but none this weekend. I remember a preamplifier years ago where one diode in a bridge went slightly leaky and killed the power transformer. I replaced the transformer and it still overheated. It took some doing to find the leaky silicon rectifier but once found the transformer ran at it's normal temperature (too hot for me but the manufacturer said that was normal)
My question is, how many of you have found a slightly leaky silicon rectifier? Except for that one I have never found another. They all have been dead shorts.
Next time I'm in Mississippi I plan to check/substitute the diodes and see what happens!

[miniman82]

Never any diode issues here, but anything is possible.

[Zenith26kc20]

I just wish I wasn't stuck in town this coming weekend. I itching to install two new 1000 PIV silicons and see what happens.