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Starting on an RCA140
#61

Mike,

This one looks like it actually "burned" burned, not just heated over long time.


Steve,

It is interesting phenomenon. Yes, dogbones, 95% I encounter or so, they increase in value over time, from 20-50% to all the way 100-150%.

But.

There is that place in some sch, where those are used as the immediate bucking resistors/dividers right after the power supply, and they conduct some significant current. Those are often 1W or 2W larger and large dogbones.

Like these in my RCA140: (R5/6/7) at the top of this picture

   


Or in Philco 60 (and some other Philcos) R19, 22 and 24. 

   

I have always found these dropping in value, unlike the rest of the resistors within the same radio.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#62

Other than one cap, which will go to outside potentikometer, which I have not put itn for that reasin (will solder it after the board is ready to be re-installed), this is how it looks now:

Top

   

Bottom

   

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#63

Hello Morzh,
That resistor board looks good !
Sincerely Richard
#64

Now is the time to start clearing and cleaning that mess that I showed before. Then the electrolytic cap restuffing and mulling over what to do about that cap can. Restuff / clip and bypass.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#65

Hello morzh, I have a General Motors console that I never finished working on, but I should. Its chassis had a big can like that too, about 3 inches square on my set, and I need to replace the voltage divider resistor.
Big wirewound one with open sections I already stuffed the sardin cans with new capacitors .

Sincerely Richard
#66

Big can by itself is not a problem; For instance, the Philco ones are mostly easy to handle. They have that panel where the cans are soldered to and that easily separates from the rest of the can which is bolted to the chassis. The hardest part is to remove the tar block. But the removal is easy.

With the RCA the very removal is the problem. Thick gauge metal can, being held by tabs of the same gauge that have to be unbent.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#67

Hello Morzh,
Yes, I have seen how that unit is mounted to the chassis .

Sincerely Richard
#68

Extracted the main elecxtrolytic cap. Ity is 16uF (10uF in the sch).
   


Now, this is the picture of the space under the tuning coils.
   

There are caps to be replaced.
The access looks like so:
   

This is the top
   

And the other side, also with caps underneath (no, not that BB). You could see it right above it.
   

Gonna be challenging.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#69

Hello morzh ,
Yes it will be a challege but I know your up to it .
Sincerely Richard
#70

I ain't up to it but do I have a choice?

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#71

BAD wire, bad!  Richard is correct, YOU can do this!  Joe

Courage will follow when Faith takes the lead.
#72

Well, today was somewhat busy, so, hopefully, tomorrow.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#73

Hello morzh,
Same here I have stuff to get done sunday too I just need to get some spunk in my repair .
Sincerely Richard
#74

Today I decided it was time to remove that RF assy.

After unscrewing the posts and snipping wires, it was still being held in place, and I almost gave up, but then I calmed down and found things that were holding it (wires to the tubes' panels). Actually not that many. There it is. The assy and what is under it.
Many wires are rubber-insulated, so will have to be replaced. They used a medley of wires, some with rubber insulation and some cloth-covered.


   
   
   


Other than that, I had to remove the interstage transformer and realized one half of the secondary is open (strange, usually it is the primary).
Also I tested the tubes, and 2A7, the pentagrid, the first I tested it, somehow did not even move the needle; then I took it out, checked the filament, gave it the look, and put it back. I worked, but it was SOOO weak, I do not think it is usable. Will have to buy a new one. Actually, might borrow one from the other two radios.
The rest of the tubes all test strong to very strong.

Also I desoldered/clipped everything going to the tuner cap. It is very dirty and needs to be washed.

So far this is it.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#75

Lurking   Following your restoration.




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