[ipwizard]

Im to the next project. I picked this 39-55 up a few months ago from a Craigslist ad. Seems to have been in Arizona a long time as the station call tags are for Arizona radio stations some are still on the air.

The cabinet is in pretty good condition. I don't plan on refinishing the cabinet on this one maybe some Howards and call it good.

[Image: http://i1129.photobucket.com/albums/m501...AG0183.jpg]

[Image: http://i1129.photobucket.com/albums/m501...AG0187.jpg]

[Image: http://i1129.photobucket.com/albums/m501...AG0185.jpg]

[Image: http://i1129.photobucket.com/albums/m501...AG0184.jpg]

[Image: http://i1129.photobucket.com/albums/m501...AG0186.jpg]

I could tell someone had worked on this radio before, the black plastic E-cap on the chassis was a giveaway, and all the lights that light up the station tags were all bundled together ad taped in a wad.
The power cord was completely junk bare wiring exposed so I hacked that off straight away. Scary thing is the kid I bought it from said he plugged it in and that the "bulbs" glowed. I'm suprised he didnt kill himself, or smoke the radio. Maybe he did cause some of the issues I found when I pulled the chassis?

[codefox1]

OK, so what's the question?

[ipwizard]

I pulled the chassis and right away noticed that one of the candohm resistors was fried (#41). Looked like it might have caught fire from all the black crap around the burned area.

I pulled the candohm out this is what it looked like:
[Image: http://i1129.photobucket.com/albums/m501...940c77.jpg]

Took it apart cause I was curious:
[Image: http://i1129.photobucket.com/albums/m501...15368e.jpg]

I replaced the candohm with another I had from a junk chassis ( I know. I probably should just replace it with modern power resistors.). Then I started the re-wire job there was no way I was going to power this thing up with all that nasty rubber wire. Whoever worked on it last wasnt to carefull and there was a lot of exposed wire where the rubber has flaked off so I skipped the testing phase and jumped to re-wire. A couple caps have been replaced and 2 e-caps re-stuffed along with some of the wiring at the time these pics were taken.

[Image: http://i1129.photobucket.com/albums/m501...bcc624.jpg]

[Image: http://i1129.photobucket.com/albums/m501...479f61.jpg]

[Image: http://i1129.photobucket.com/albums/m501...756af6.jpg]

That big freaking mess with the more modern e-caps and the resistors was a previous repair not my doing. I had to replace the octal socket for the 6J8 OSC/DET tube. The socket was cracked and socket 3 was pushing through the back of the socket. Luckly I had a spare from that junk chassis I got the candohm from (40-205).

[ipwizard]

OK, so what's the question?

No question just detailing my new project. Or is that not allowed?!?!
Wrong forum?

[ipwizard]

Pulled the power transformer and cut back the exsisting wrotten wiring and spliced on new wire. Covered the splice with heat shrink pushing it down in between the windings as much as possible. Once done I slathered on some liquid tape to seal and stablize the new and existing wiring.

The transformer looked like it got hot a somepoint some of the paper seperating the winding has turned a dark brown. It ohm's out ok, hopfully its still good.

[Image: http://i1129.photobucket.com/albums/m501...af0cb3.jpg]

[Image: http://i1129.photobucket.com/albums/m501...1d25ac.jpg]

[Image: http://i1129.photobucket.com/albums/m501...9bf692.jpg]

[Glenn Roberts]

I got one of those from C-list about a year ago. Do you have the mystery control to go with it?

Glenn

[Bob Andersen]

Nice job on the power transformer and good luck with the rest
I have the same chassis plus mystery control but no cabinet for the radio. I was thinking of leaving it out in the open to demonstrate how the mystery control works. Of course, I need to actually get it working first.

[Ron Ramirez]

Ditto Bob's on the power transformer, Keith. Liquid tape...great idea! In my opinion, lots of insulation in those power transformers is a good thing.

No question just detailing my new project. Or is that not allowed?!?!

I don't think Codefox meant any harm, it's just his sense of humor.

[ipwizard]

I got one of those from C-list about a year ago. Do you have the mystery control to go with it?

Glenn

No I dont have one for this set at the moment. I do have one for my 39-116. Im looking for one for this set which should help me when I sell it.

Ditto Bob's on the power transformer, Keith. Liquid tape...great idea! In my opinion, lots of insulation in those power transformers is a good thing.

I agree as some of those outer wires that have broken away from the wax flop around a lot and I worry they will break way down inside. I hope the transformer wasn't hurt when it was powered on before I got it. If it ohm's out is it a good indication the transformer will still be up to the task of powering the set?

[Ron Ramirez]

If it ohm's out is it a good indication the transformer will still be up to the task of powering the set?

Generally, yes, assuming there is no evidence of shorts between windings or any evidence of serious overheating (as in burnt fish paper insulation).

[ipwizard]

Some of the paper not seen in the picutes I posted are a dark brown, and it looks like some of the wax ran out of the transformer at some point. I dont know if that burnt up canohm hurt the trans. or what ever caused the candohm to burn. The bottom tap (candohm) which was closest to the burn is connected to the center tap of the 80 plate winding.

Schematic: http://www.nostalgiaair.org/PagesByModel...013299.pdf

[Ron Ramirez]

Hopefully the Candohm sacrificed itself and the transformer is OK, if it specs out OK.

You've gone to this much trouble already, might as well try it by bringing it up slowly on a Variac and keeping a close eye on current draw, voltages and such.

[codefox1]

Agree as usual, I like to put in an old fashioned analog current meter in line to see what is going on. Have a few in ranges from 5 amps on down. Nice old school tools.

[ipwizard]

Would it be worth while to power it up on the bench and check voltages. I know would be high with no load on them but i could atleast see if the trans gets warm or hot wihtout any load on it.

Worth a shot?

[codefox1]

Agree with all. I would also wrap as much electrical tape as possible without undue crimping of windings when the bells are tightened up again. BTW scour and spray the inside of the bells as well when you have them off. Also soak the bolts and nuts in oil so you don't bust them when you put it all together again. I think you're all set.