Twitchy RCA CTC17 1966 Screen

[jbunnelle]

Hi guys, many thanks for the checklist and recommendations! Yes, a fundamental understanding is what I need, so that book would be ideal, I will grab a copy. I started looking for an old set somewhat naively, but Damen took me aside, opened up the back of a couple of his sets to warn me of what I was in for, asking if I intended to make this my main set or decorative. In other words, doing due diligence as a responsible, conscientious collector, which I respected and understood. Having no background in electronics, it is intimidating for sure; when you said "respect for voltage", yes, that's an excellent way of putting that. I'm 43 so I did grow up at the tail end of these days, have memories of smoking sets and grandfather's accompanying tirade, the man in the van coming, etc. But I think I am up to the challenge! Thanks for the warm welcome.

[DaveWM]

some selected reading on things like ohm law and the understanding of the meaning of voltage current and resistance will be a good start. I am sure there is tons of reading material on the subject. You will also need some tools of the trade if you intend to work on the sets.

soldering iron and gun
hand tools including wire stripper and diag cutters, some precision screwdrivers.

diagnostic equipment should be at a min:

DMM (digtital multimeter)
a nice analog VOM like a simpson 260
a VTVM (vaccum tube volt meter)
an HV prob.
and and bunch of jumper (aligator clips on lengths of wire).

most of the older stuff (like the 260 and vtvm) can be had for a fraction of the orig cost, but may need some work themselves.

I mostly use the DMM and the 260, the VTVM is close to a DMM but I prefer the analog readings I get, also since they were used back in the day when much of the service literature was published, I trust the readings from them over a DMM for such things as voltage readings given on schematics.

the HV prob is handy for setting up color TV High voltage (and a safe way to discharge a CRT which can hold a high voltage charge and give you a nasty shock).

The main thing is safety. These sets were designed to be serviced by folks that had training (school or OJT) and can be dangerous so you really need to pay attention and be safe. Again there is a lot of data on this you just need to search it out.

[Findm-Keepm]

Looks to have some foldover, so the 50uF cap (C507) in the cathode circuit of the Vertical Output Tube (Should be a 6GF7) is BAD. Always get rid of the original, and check any replacements.

Cheers,

[damen]

Got him back up and running I pulled the vert lin. pot and took it apart and cleaned it tensioned the contacts and lubricated it and all is well again. We also replaced horizontal osc. 6fq7 tube that was a little weak. I added a picture of his set working a couple months ago when he got it from me.