whats the chances of the big power resistor in the back being good? just wondering if I need to start planning a power resistor buy....

More often than not they are still good. You should be able to verify that with an ohmmeter because the values are printed on the schematic.

But if there was a short in one of the B+ lines that resistor would overheat and eventually open. They were also notorious for insulation failure causing the resistance element to short to the metal housing of the resistor, I have seen more than one with a hole burned through it.

well its coming along, got the under chassis can and one of the top mounted cans restuffed, so two more to go. Tested a bunch of 6SN7's and the HOT all tested fine.

got thru about 1/2 the paper caps, ran out of .047's so will have to pick up some more. got the vert integrater done, that was kinda tight. I noticed the old caps were dressed pretty close to the chassis, I wonder if that was to help keep out horz pulses? Tomorrow I think I will bone saw off the two cans that are up front and easy to get at now that I have removed the 12LP4.

got the CRT masked off and sprayed with slick plate, wow, that came out nice. got the remaining caps so will press one.

Sounds good. Could you post some pictures?

will do soon Tom.

hit my 1st real snag, the tuner it TIGHT, i can turn it but its def froze up. Hoping some light oil around the shaft bearing points loosen it up. I have read here that its not a lot of fun to open up.

all film caps are replaced but for one .018 1kv that I did not have. hope to pick up tomorrow at the local surplus store or the hamification meet. then two more can caps to go.

I am not quite sure how old your set is. If the tuner is anything like mine, you have to disconnect all of the wires going to it and then unscrew enough screws to get it out of the metal box it is sitting in. You would need to either label the wires or take some close up pictures so you can get it hooked up again. If you do take it out, take the opportunity to spray some contact cleaner on the switches.

yea its inside a metal box, has an opening in the back where I see a term strip with several connections. I cant tell if the term strip is attached to the tuner or is just a tie point that would stay with the box the tuner is in. At this point its loosened up some from the lubrication, I was able to get at some of the internal bushing points with my oilier and an extenstion. Better now. I will for sure leave it alone until I get a chance to see how the set works.

The terminal strip is part of the tuner, and you have to disconnect the wires going from the chassis to that strip in order to remove the tuner. No telling what RCA engineers were thinking at the time, since they built the tuner area of the chassis in those years considerably stronger than it seems to need.

Detent failure and shaft breakage was very common on those, shops used to stock the tuner shaft/detent assemblies. Once you get the set working, definitely worth taking the tuner out to pursue freeing it up further and cleaning the contacts while you have it apart.

its pretty well freed up now so hopefully no problems there. I just have to sit down and do those last two caps on the front of the chassis.Still looking for my camera, its around here somewhere....

last two cans stuffed, I made up a series connected .1+.022 to get the .018 cap, so all that needed now is the test CRT installed and then will variac and hope the B+ voltage divider resistor is ok.

no joy. Vert is running (I hear it) but no horz. then the 820ohm section for the power resistor started to arc out and I lost my 135v b+. I got that back in line but will need to check the horz. the HOT is pulling about 50ma and the grid voltage seems too neg. I get the B&K analyst out and give it some drive and see. Normally with a neg grid I assume osc due to grid rectification of the drive signal, but this set has a fixed bias off the neg B+ so I cant assume anything. I do have plate voltage at the cap and the screen voltage is there but a bit low (perhaps due to lack of drive).

scope was easier so I checked the HOT grid, flat line, checked the horz osc tube, while clipping on the trans former I would get a signal but it was all wrong looking, moving the clip on from the scope caused the drive signal to suddenly appear and bingo I got a good HV and a bright raster on the test CRT. So now I can invest in a bit more time to resolve the power resistor and futz around with the horz osc coil. not sure if its a bad connection inside the can or around the can. I will start by just reflowing all the pins around it but its looking good so far.

getting triple images horz so looks like the horz osc is running off freq. May as well start by replacing the mica caps, I am not checked out on how to set the horz freq up on these old sets.

horz is locking in at 12.588khz. free runs around 12lhrz so clearly there is a problem in the feedback timing.

If it is anything like mine, there is a horizontal frequency coil and a horizontal stabilizer coil. Both are adjustable and both are in one can. In my case, the Sams had an adjustment procedure. If you have the same circuit, there is a quick adjustment procedure that does not need you to use a scope. You short out the stabilizer coil with a clip lead. Then adjust the frequency coil the get the right frequency. Then remove the short on the stabilizer coil and adjust that to again get the right frequency. I sometimes think that this method of adjusting the stabilizer coil yields a more stable set then the procedure using the scope.

I tried adj both the top and bottom coils, no help. I did notice that one of the coils is supposed to be 35 ohms, mine is 22 ohms. I also noticed that on startup I get a single pic very briefly then it goes to multiple. I could shift the free running freq some with the bottom adjustment but not much.