I've been blessed!

[old_tv_nut]

Update - I picked up the rebuilt 21FJP22 over the weekend. Now taking a good look at how I might mount it. It's less a question of knowing what I might want to do and more of how I can do it myself with nothing in the way of shop tools. I would not like to do it the way Tom did for a couple of reasons:
- The existing yoke mount is part of the poly cone in the CTC-5, not metal like Tom's pix;
- The example pix I have of a CTC-5 with factory kit show a metal shroud that is near the face of the tube and therefore away from the HV connector.

The shroud, which apparently is what holds the tube to the bezel, has four metal tabs that are screwed to the existing mount points for the 21AX, so the tie rods are not needed. It also has the yoke supported by the neck of the tube, so it seems the support by the cone is not needed. I tried the yoke on the 21FB neck, and while it's slightly loose, it seems like a small bit of shimming will fix that.

Now my problem is to figure out how I can fabricate the equivalent of that mounting kit.

Of course, if a good 21AXP22A would show up.....

[old_tv_nut]

Still working through cap replacements - replacing paper/wax caps with film types.

I got to the .047 600V that is across the line. I know this needs to withstand whatever mother nature and the power company might throw at it, so I'm wondering what exactly to use to replace it. Any suggestions?

[John Folsom]

I no longer replace the power line decoupling capacitors in sets. I simply remove them, along with any resistors from line to ground. I have not found operating old sets without these components causing any problems. This also seems to reduce the mild shock hazard this connection from line to chassis provides.

[radiotvnut]

Originally Posted by old_tv_nut

Still working through cap replacements - replacing paper/wax caps with film types.

I got to the .047 600V that is across the line. I know this needs to withstand whatever mother nature and the power company might throw at it, so I'm wondering what exactly to use to replace it. Any suggestions?

If you decide to replace it, go to www.justradios.com. They sell "safety capacitors" that are designed for this purpose. Of course, you could try the set without it, like has already been suggested. I've got many radios from the late '20's and early '30's with no line bypass cap and they seem to work just fine.

[old_tv_nut]

Originally Posted by radiotvnut

If you decide to replace it, go to www.justradios.com. They sell "safety capacitors" that are designed for this purpose. Of course, you could try the set without it, like has already been suggested. I've got many radios from the late '20's and early '30's with no line bypass cap and they seem to work just fine.

Thanks for the link - I just took a look and also will check them out for any others I'm missing.

[shimniok]

I don't know squat about vintage tv's except those I grew up with... but man that is gorgeous!!!

[old_tv_nut]

I just came across an ad for a 1964 Heathkit roundie, which gave me the idea that the construction manual might be a good source for an idea on how to mount the 21FJP22 in my CTC-5.

Any ideas where I could find a manual?

[old_tv_nut]

Looking at the RCA field service guide, I see there are diagrams of the CRT mounting for the 21CYP22 with it being held in place by the magnetic shield. However, although it mentions padding, it doesn't give any details, because in replacing the tube you would just use what was there from the factory. So, I know some more, but I'm still left scratching my head on how much and what kind of padding and where to put it.
The CTC-11, which is the first using the 21FJP22, has similar mounting, but padding is not even mentioned. CTC-12 and later use a mounting strap and special brackets that grip the edge of the screen. I don't think there's any way I could safely duplicate that.

[old_tv_nut]

OK, now I need some advice. Will be firing up the recapped chassis soon, and need to know what I can do with it disconnected from the CRT.

I think the yoke has a jumper wire that disconnects the power to the horiz output and maybe the vertical when the yoke plug is pulled. Correct?
Do I need to also pull the H output tube or anything?
What else doesn't work with the yoke pulled? AGC (due to loss of gating pulses)?

Thanks for any guidance here!

[stromberg6]

You need to connect a resistor to "absorb" the current normally drawn by the horizontal sweep/hv section.

From the Sams PF #358: "The high voltage should be disabled by removing the fuse (M3). Connect a 2500ohm 100 watt resistor from B+ side of C2A (filter capacitor) to chassis". That should do it.
Any suggestions from other members?
kEVIN

[John Folsom]

I do not recommend the resistor loading technique called out by RCA. It is an enormous bother with no real advantage. Much easier and better to just put the yoke on the bench along with the chassis and fire it up. This allows all the gated circuitry (AGC, color burst, color amp, color killer) to function normally. I take the loose end of the HV cable and insert it into a glass jar or drinking glass, and tape it in place. This insulates the end of the cable and makes the set safe to operate on the bench. This way, all the functions of the set are operating, and comprehensive fault isolation and troubleshooting can proceed.

[old_tv_nut]

Having everything working sounds best to me - have to be careful anyway, so the HV thing is doable. Not having the required 100 watt resistor clinches it.

[old_tv_nut]

Finally got the nerve to fire up the chassis, and I'm getting sound from the speaker, with no apparent overheating. Just using some clip leads for an antenna. Let it run a half hour. Power transformer is cool so far - worried me a bit because I found some brown stuff(wax?) had dripped out the bottom onto the wires. Flyback primary is a little warm, secondary is cold.

Still havne't figured out how to make a shroud-type mounting for the glass CRT - more head scratching to come.

Onward!

[zenithfan1]

I have some of that stuff oozing out a bit from the bottom of my power transformer too. I think it might be ok though, I think a lot tof them do it. There is also a bit dripping from the one in my 9. Just keep an eye on the temp.

[bgadow]

The power transformer in my -5 lost a lot of wax, too, but it hasn't given me any trouble and doesn't seem to be losing any more. Not many sets put the transformer in a box like that.