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  #1  
Old 04-16-2015, 06:04 AM
DeathOpie DeathOpie is offline
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I got directed over here from audiokarma. I took a flyer on buying an RCA Victor 99K radio. I've never really done anything like this before but I figured I'd give it a shot to either restore or modernize. I've been concentrating on the cabinet right now. Got it stripped. Needs a little veneer work on the side, near the bottom. It has some black streaks on the front that I've almost got taken care of using wood bleach. Almost ready for stain. The glass is intact and the push buttons are there. The bezel has a crack, but not too bad.

The electronics could be rough. There was a mouse house in it. One tube was shattered and there's a decent amount of rust. The speaker cone is really bad. Not sure what to do about it. I don't know much about these old style speakers. Anyway, I'll be checking in here for advice and tips. Here's a link to the post on audiokarma I made.
http://www.audiokarma.org/forums/sho...d.php?t=650608
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Old 04-16-2015, 08:24 AM
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Welcome aboard!
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Old 04-16-2015, 11:58 AM
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Welcome to VK.

I read your thread on AK and saw the pictures (I'm a AK/VK member that spends more time on VK). That set should be reasonably electrically restorable. Chassis rust like that is no problem you could leave it be and the set will be fine. The only time rust is a problem is when the metal turns to swiss cheese from it (at that point rare parts may be compromised). I've restored a few rodent condos, and as long as they have not chewed up the cardboard RF/IF coils/transformers there is little permanent damage they can do worth worrying about. Tubes for this era of set are easy to find if you browse the web, and some can be quite cheap. The caps should run you around 10-35$.

As for the speaker cone is it gone or just torn with a few holes no bigger than a a silver dollar? If it is the latter silicone caulk and coffee filter paper should be able to fix it. If the former test the voice coil and field coil, and if both are good look into having it re-coned (there are services that do it for ya). If voice or field coil are bad look for another speaker they are out there.
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Old 04-16-2015, 01:02 PM
DeathOpie DeathOpie is offline
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Thanks for the advice Tom. The speaker is ripped completely across one side and has a couple of other smaller tears. It just looks really fragile, but I haven't given it too close a look yet. I was trained as an electronics tech, but I haven't done a whole lot circuit level troubleshooting. I am pretty good with a solder iron though, so I'll give it a go. What should I look for on the speaker coils, just a low ohm reading?
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Old 04-16-2015, 05:04 PM
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Voice coil should be under 30 ohms Field coil (if present) should be somewhere between 200-5000 ohms.

I've fixed and seen fixed speakers torn from the edge of the coil to the outer frame. If enough of the paper is there it can likely be fixed. Paper of that age can be a bit fragile so don't bend it too much...Gentle persuasion is the key to lining it up for gluing.

Repair is often as simple as a recap, or occasionally some signal tracing.
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  #6  
Old 04-18-2015, 07:52 AM
DeathOpie DeathOpie is offline
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Some pictures. Decided to remove the veneer on the curved part. It was a real bitch. The old stuff has cracking and a lot of bubbling. Repair would have been tough. I've never done veneer before, so it should be fun.
Attached Images
File Type: jpg IMG_0443.jpg (73.6 KB, 28 views)
File Type: jpg IMG_0445.jpg (101.2 KB, 26 views)
File Type: jpg IMG_0446.jpg (115.7 KB, 27 views)
File Type: jpg IMG_0456[1].jpg (67.3 KB, 21 views)
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Old 04-18-2015, 06:40 PM
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I'd advise before you get into the cabinet work too far, do some checking on that chassis. Otherwise you might have a nice cabinet and no radio to put in it. Refer to the schematic and ohm out all of the coil windings for continuity. The coils look pretty moldy. Ditto the power transformer and output transformer windings. Tubes, caps, resistors, all can be replaced if bad, but bad RF coils can be hard or impossible to find, and power transformers can cost a lot.
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Old 04-18-2015, 08:36 PM
DeathOpie DeathOpie is offline
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Thanks for the advice Reese. If I never get the radio working its ok. This has been my training project. I got the veneer on today and it looks great, except it needs to be stained darker to match the rest of the console. If it looks good I'm happy. I could always modernize it. If I get the original radio working that would be great.
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  #9  
Old 04-20-2015, 06:50 AM
DeathOpie DeathOpie is offline
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Replaced the veneer and stained. The new veneer looks lighter in the picture due to the flash, although I may put on one more coat of stain before I put on lacquer. Do you guys usually use spray lacquer? That's what I planned on using, just afraid of a drip ruining everything.

Alright, why the hell is the picture sideways when it shows up correct in the folder?
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Last edited by DeathOpie; 04-20-2015 at 06:57 AM.
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  #10  
Old 04-23-2015, 01:24 PM
DeathOpie DeathOpie is offline
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I made a list of the paper caps to buy at JustRadios.com. According to their advice I ordered all the caps between .001 and 1 uf. The two bigger caps are in large cans listed as 16 and 25 uf and appear to go to the speaker. I think I'll order them too, but what voltage should I get. It's not listed on the schematic. Would 450V be adequate?
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  #11  
Old 04-23-2015, 01:45 PM
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Yes, 450V will do. I have a 111K, with the same values, and used 450V caps.

Cheers,
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  #12  
Old 05-03-2015, 07:59 AM
DeathOpie DeathOpie is offline
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Well, it's done cosmetically. Came out pretty decent for my first go round. I found cloth with gold thread in it. I like the way it came out. I thought it might be too dark but it looks good. I'll see if I can get the electronics working now.
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  #13  
Old 05-09-2015, 04:06 PM
DeathOpie DeathOpie is offline
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Well, I did a cap replacement and patched up the speaker and replaced the ac cord. Fired it up with a dim bulb tester with rectifier tube out. Looked good. Put the rectifier tube back it and the bulb is glowing pretty good and and no sound. Damn.
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  #14  
Old 05-09-2015, 06:26 PM
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Did you check the audio output transformer?
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Old 05-09-2015, 10:33 PM
Titan1a Titan1a is offline
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I have an electrically restored 1939 Zenith 7S363. When I first saw her I felt a rush right up my spine. It initially cost $150 for the purchase but took another $450 dollars in parts and labor. I have cabinet work in the pipeline but have other expenses pending. It's playing now. Warm, rich tube sound! No other radio in the house, including two surround-sound receivers sound better! Yeah, I'm on the lookout for another.
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