Ctc-12

[DaveWM]

this is the nice looking CTC-12 I picked up in Jax. It was extremely clean, clearly a non smoker and a inside set its whole life. Very plain jane faux wood single speaker, VHF only set. the faux wood is mint. When I got it I oped up the fly cage, to be rewarded with NO fly, just cut out with little care. the original plan was to take a working CTC-15 with a ruff cabinet and just swap the chassis, but the way the vert out is mounted in the 15 would not let it fit inside the 12 cabinet (I suppose I could swap out the degauss holder which I think is the only thing messing it up, but I figured I may as well get the 12 running as I like those chassis better).

I was also missing the focus coil, focus cap, and the 47meg load resistor (I had a 66 meg but decided I may as well use the correct parts). I had a correct coil but not the 130pf and 47meg 1 watt, found them at talon, so they are on the way. I prob could have rigged up some caps (I had 39pf 6kv) in p but I hate doing hack work.

I spent some time observing how a 12 is connected to the focus coil/yoke/damper, so I have a pretty good idea of how its supposed to go.

The chassis looks pretty unmolested, so I will do a slow power up montitoring the B+ volt/current and the HOT current when I get the fly back together.

The only repair I could see was where one of the jumper wires that normally runs on the top of the chroma board was missing, but found it installed on the bottom of the pcb. These wires frequently corrode and break resulting in a hue on the screen like one of the screen drives is turned all the way up. I may install it correctly if I need to do any cap replacement, which is typical on the difference amp grid coupling caps that get lossy from the heat.

there are a couple of the white ceramic tube caps I will cut the AC bypass cap out so it does not explode on me, will leave the others alone for now. I cant really test them as my cap tester does not go up that high, but I have left them alone in some sets and they are fine (not the ac bypass but the ones on the audio out and vert out primaries.

I tested the CRT by sticking in a working CTC-16 chassis just to see how the CRT looked, it tested not so good but is seemed to make a pretty good pic so maybe my tester is not so good. The best test for a CRT is in use anyway.

I had to splice on some wire to the focus and the red yoke lead, as it had been cut short by the hack tech that removed the fly. I was careful to make a neat splice and then slipped 3 layers of heat shrink over the spice.

the boost and damper connections were also cut short, but I will just replace the full length there as there are no connectors/sockets involved. I need to splice the bottom coil as the wire from the fly is connected under the covering (not a tab to solder too) and of course that wire was cut short as well.

Lastly there is a wire that comes from the sweep board that connects to where the focus load resistor should be grounded. I never noticed this on any other RCA sets, earlier sets had pots (no coil) and later sets used a boost diode to supply voltage for the vert sweep. Another reason to use the correct resistor (47 meg) I suppose.

I really like this set for its size, its not any bigger than a metal cabinet, and the CRT looks like a bonded face with NO cat, imagine that.