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Picked up a 42-380 for 25 bucks. Cabinet isn't too bad except for some chips in the veneer at the rear edge of the sides. I think they can be repaired. The radio works pretty well. The faceplate is warped but all knobs and buttons are there. I cleaned the pushbutton tuning mechanism as it was filthy and very sticky. Now I cannot get most of the pushbuttons to stay in once engaged. They just pop right back out. I have to physically hold them in. Is there some way to cure this? Thanks again.
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Good deal! 
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Very likely the pushbutton mechanism needs the mixture of old grease and dirt cleaned out of it. Most of the time these have a spring loaded bar that catches the shaft of each pushbutton as it's depressed and lets go of the previous button at the same time. So either that bar is not catching or the shafts are so gummed up that they won't go all of the way in. If you are planning on restoring this set electrically I believe you will have to remove the pushbutton assembly to access some capacitors and resistors that are buried under it, that would be an ideal time to take it out and wash the mechanism down with varsol/mineral spirits, degrease, and then relubricate the appropriate parts.
Regards
Arran
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Did you ever see an old time watchmaker take apart a mechanical watch, throw all the parts in oil, and get it back together again? I thought the first one was a madman. He had a shop, and worked behind the front window of the shop. Fix did my very old chronograph for equivalent of $5 then, $25 now, I reckon.
So you can refurbish that switch mechanism. Many were designed to operate without lubrication, just springs and gravity to lock down little detents. A little diversion from electricity for many of us. Designer was also probably a madman.
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City: Kokomo, Indiana
This set has been on the back burner for a while. I have been stripping the cabinet off and on as weather and time permits. Other than a little loose veneer, and some chips in the sides at the back edges, it's not too bad. I stripped off the photo finish junk. It was pretty rough and I hated the color. Actually the wood underneath is figured decently and I believe once finished, will look nicer than it did with the fake stuff. As this set is pretty common, I'm not worried about absolute originality. I found a site that offers unbacked veneer "sampler packs". I'm going to order one of those as it looks to be enough walnut "sample" to do what I need, and if it's too thin I think I can double it up.
I had used some electric motor cleaner on the switches...because it's what I had. It helped some. Took forever to dry. Yesterday I found some deoxit (?) contact cleaner. It is a red color. After spraying down the switches with that stuff they work pretty good now. I made a tuning dial pointer for it out of some really thin aluminum sheet that came out of an old laptop case. Painted it red with some leftover red touch up paint that I had from the wife's Miata she had a few years ago. Looks great too. The set was working, but low on volume. I did a little "freestyle" aligning (I have no test equipment yet) and now the thing works pretty well considering I haven't re-capped it yet. No hum. Still need to re-string the dial. That'll be a weekend project.
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You are certainly a very creative and resourcefull person, and we can all learn from your techniques. Of course you should re-cap and re-carb for long term reliability. Ancient signal generators and modern digital frequency counters are available for less than a surf.n.turf dinner for two.
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Yes, very innovative!!! That is what makes this hobby great!
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City: Kokomo, Indiana
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City: Clayton, NC
Or craftsmanship.....
Something I personally value is craftsmanship. It is something I am constantly learning, mainly from the examples of things done by others.
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Magic Smoke...ever heard that term? Well...after running the 42-380 for a couple of hours the other day while aligning it and just listening to it...I decided, yesterday, to re string the dial and attach the home made pointer. After an hour or so of fiddling I was done and everything worked smoothly I decided to fire it up (pun intended) and set the pointer on the dial string so it lined up with the correct channels. I turned it on and while waiting for it to warm up I noticed that the 6X5G tube, the rectifier, looked like a sparkler internally for about 1 second, then the Magic Smoke escaped from the bias resistor strip under the chassis. I said many creative and colorful things similiar to shucks, darn, heck fire and so on. After that I got fed up and went in the house. Briefly looking at the schematic I'm guessing one of the filter caps shorted out. I'll add it to the list of non-working radios now that need troubleshot and repaired. Fun Fun Fun 'till your daddy takes the T-Bird away.
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The 42-380 should have an 80 rectifier. 6X5s were in other 1942 models, possibly you have an undocumented variant OR someone has "modified" it.
The 6X5G tube had a bad reputation for internal shorts that would fry other components in your power supply circuit, including the power Transformer. STRONGLY recommend you replace it with a 6X5GT or metal variant.
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State, Province, Country: Indiana
Personally, I would go a step further and replace the 6X5 with silicon diodes. The 6X5 is just too unreliable.
--
Ron Ramirez
Ferdinand IN
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Agree with Ron, the 6X5 is one of the most notorious of the bads, and is mentioned at least once a week on radio forums. Just can't stand much abuse, but runs for decades in test equipment and other light load applications.
But you do need to make sure filter caps and paper caps have been changed out and installed correctly. Diodes will somewhat raise the B+, so you might want to add a shunt resistor to tame it. One of the bolt on 25 watt types to dissipate heat to the chassis is usually a good and practical soloution. Value? More of an art than a science, but Mr. Ohm will get you in the ballpark. OK, 150 ohms or so, probably. Fuse the set if it has not been done already. Best.
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With the Holidays (and the end of the world looming)....   I haven't had time or cash to put into the radio deal. I have every Monday off and last Monday I got bored and decided to work on the 42-380 cabinet some more. Sanded it some more and then wiped it down. It really didn't look too bad. I glued down the loose veneer on the top. Then for giggles applied some pre stain wood prep. Then I temporarily installed the reproduction escutcheon I got from Larry Bordonaro at Old Time Replications (beautiful piece). The wood on this thing is very nice. Even the areas that had the photo finish has some decent wood. There was a few areas where the wood color was much lighter than the adjacent wood so I applied stain in those areas, little bit at a time and immediately wiped it off. I did this until the overall color evened out as close as I think I can get it. Now I think all I'll need to do is repair the chipped veneer at the back edges of the sides, and clear lacquer it. Pleasantly suprised considering how crappy it looked when I bought it.
Can't wait for warm weather so I can finish the cabinet. Hopefully soon I can get the chassis working again. I know, I know, sorry but I just can't post photos at this time. After the wife opens her Christmas present, then I should be able to...............
Not really informative I know...just rambling.
(This post was last modified: 12-19-2012, 06:49 AM by Groundhog74.)
Posts: 227
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Update on my 42-380 project: With the weather warming up I was able to get the cabinet finished. Not a museum quality refurb (I call it a refurb, not a restoration. Restoration to me means it's back to original factory new condition, this is not), but I like it. Did not re-do the photo finish as the wood underneath was quite nice. I ordered some 6X5GT's from John Kendall's Vintage Electronics. I ordered 4 but he had a note on the page stating he was overstocked and he would send 2 for 1. So I got 8 for the price of 4!!! Cool. Figured since the set smoked, I may need several until I got it running again. Replaced the toasted 6X5GT, repaired the Candohm resistor that smoked and replaced the weak tubes with some known good ones I got from another 42-380 junker I got for 10 bucks. It's alive again, but just barely. I get 1 channel (a local channel about 5 miles from home) and there is very little volume. I still have a weak 7B7 tube in the socket adjacent to the 2 XXL tubes. I'll get that replaced and start on the re-cap soon as time permits. Prior to releasing the magic smoke, the set received fine and had volume to about the medium level I would guess, not full booming volume. Something else must have gotten toasty during the "smoke test". At first this unit was purchased just because it worked and was real cheap, but it's kinda growing on me. The wife says it's one of her favorites looking radios right now.
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