Anybody ever have a Philco that didn't need to be rebuilt?
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About 10 years ago I bought a 37-670 table model without the longwave band at a fleamarket. The case would have been perfect except for a small cigarette burn on the top. The seller assured me that the set worked fine. I figured yeah sure, I heard this before. I tried the set at home and sure enough the set played perfect. I was sure that if I pulled the chassis I would find new filters stuck underneath. I checked and it was all original. Even today, the set still plays perfect. The only thing I did to it in the 10 years is to replace the metal 6J5's and 6F6GT's with original Philco branded G type tubes. I never did anything yet about the burn on the top edge. The only thing I can guess is that the set was used regularly over the years and it kept the filters formed. Anyone ever have a set like this work well with no rebuild?
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Fred I purchased a 46-1209 from a guy in Cleveland and it played fine and was totally original. It was just starting to pick up an audible hum when I sold it on ebay, the buyer was totally pleased.
Fred,
I've got a 42-321 still running on completely original electronics. It's got a couple of non Philco tubes but even the filters are original with no hum. It was a lucky bad picture buy on ebay, great radio, even had a Installing and Operating instruction sheet folded up next to the chassis.
Chris
Sure! My 511 still runs on its original components. I wouldn't trust that 'condenser pack' to last long seventy-five years on though.
All I've done so far is to replace the tubes with the original S-type tubes and get all the info I need to restore it. It looks to be a real chore!
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Hi Fred,
Not a Philco, but I do have a 1946 Zenith 8G005 TransOceanic which is 100% original and still playing strong.
I have had a few 1930's radios which seemed to play OK at initial testing, but I never had nerve enough to play them regularly without at least a partial recapping.
The problem with playing original radios like these is the possibility of damage to major components if caps should fail. Not so much of an issue with my T-O, since it is an AC/DC radio with no power transformer at risk, and neither the rectifier or output tubes are particularly rare or expensive. But this is not the case with a nice AC radio like your 37-670.
The problem with electrolytic filter caps is that they can fail two ways, they can either become leaky, or they can short. When they leak this shows up as increased hum, telling you something is wrong and giving you the chance to replace the filters. Usually no harm is done if dealt with promptly. Shorting is more rare, but certainly does happen. Unfortunately when it occurs it is usually without any warning, and depending on whether it is the input or output filter cap which shorts the speaker field coil, rectifier tube, and/or power transformer are at risk. At a bare minimum, if I were operating a 1930's radio with original filter caps I would install a line fuse ahead of the power transformer. In the event of a short this would hopefully protect the transformer, but not necessarily the rectifier tube or field coil.
Another issue is the coupling caps to the power output tube grids. If leaky (and yours most certainly are, to some extent) this is upsetting bias on the output tubes, might not be too noticeable for a while, but if it gets worse the output tubes and output transformer are at risk.
Each person has to make his own decision on whether to leave an original radio "as-is" or not. If played only very rarely, maybe it is worth leaving it original and taking the risk. But if played more often, my best advice is AT A MINIMUM to replace the electrolytic filter caps and the coupling caps to power output tube grids.
If a person decides to leave the radio original and plans to play it on even the rarest of occasions, he should at least use an AC ammeter and see how much current it is drawing. If substantially over nameplate rating this is a sign that its power supply is being stressed and it should not be played again until serviced.
Poston
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Poston is right, guys. If you run an AC-powered radio (with a power transformer) on original components, you're taking a gamble every time you power it up - and, eventually, your radio is going to lose.
When I was young and foolish, I had a Model 96 lowboy that was still running on original components. All was well until the day I turned it on and BOOM! Bye-bye, power transformer. I replaced it with a power transformer from a dead 112, but the radio did not get played again until every bakelite block and metal can capacitor had been rebuilt. Lesson learned, and never forgotten.
It does amaze me to find 1937-era aluminum electrolytic capacitors which are still good, and still full of their liquid electrolyte. Do I leave them in the circuit? Absolutely not! They get drained and restuffed with new electrolytics.
--
Ron Ramirez
Ferdinand IN
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Yes my Philco 610 shouldered tombstone has only had some tubes changed . The 3 original liquid filled filter capacitors are still in place , the chassis looks like new .I have had this radio a long time and played it as pleased with no trouble .
I just played it 2 days ago & its still fine .
I have had several 50`s radios that worked fine after cleaning the controls .
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I'll have to side with Ron and Poston on this one. If it's an AC powered radio and it's over 40 years old, I automatically change the electrolytics. I know of someone who cooked the transformer in a beautiful 37-61 cathedral because "it played with a little hum" and they didn't change the caps. Come on now guys, is saving about 8 or 10 bucks on capacitors worth risking it? 
Tom
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Actually, this wasn't a debate on whether to rebuild or not. It was more a statement on sellers claims and in my case goes back before there was an ebay. Many times a seller would assure you a set works works when it was really nonsense. I was amazed that this 37-670 actually worked. It still does even today although it will get rebuilt when I get time.
And talking about weird sellers, about twenty years ago, I found a junk store in the Manyunk section of Philadelphia (which today is built up with night clubs and art galleries) and the dealer only wanted to sell me his "Philasonic" TV which was actually a 17 inch Predicta. He wanted too much money; I turned it down.
Fred R
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Yes, a PT-93, that was used in the movie "Seabiscuit", and is all original, and plays very well. It needed to have one tube replaced after about 6 months.
Which to me still qualifies as original.
Dan('  ')
I found a 41-280 with a near mint unrestrored wood cabinet on eBay in November of 2006. The dial face and push buttons had shrunk and looked terrible. This was probably why no one bid. After confirming that re-production parts where available I bid and won the radio for $25. After I got it home and poked around the chassis I decided to power up. The power cord was so dried out that it literally turned to dust when you bent it. I used a temporary plug and wire.
I have been fiddling around with old vacuum tube equipment long enough to know what happens when you slam it with full power after its been sitting for years, so a few years back I built a bench test power supply that uses the power limiting feature of a light bulb in series, a variable transformer, in-line fuse, GFI receptacle, ammeter and a voltmeter.
Many times as you begin to dial in power with the variac the bulb goes bright. That's when I am thankful I built this gadget. I've never done any damage to a set even if there is a catastrophic failure so long as you stop there.
Back to this 41-280. I powered up to about 25 volts and looked and sniffed, then 50 volts, 75 and 100. After a while I heard some audio, I tuned in a local strong station and it came in so load and clear that I had to turn the volume down.
This radio is 100% un-restored except for a tube I replaced later on and maybe one that someone else did years back. I can't explain it. I haven't recapped yet so when we listened to Christmas music over the holidays it was through said bench power supply in the bulb safety mode.
I get no AC hum, no tuning static, no scratch in the volume and only a slight inconsistency in the middle of tone control range. I even get reception on short wave with the built in antenna.
I suppose the environment in which this radio has lived all these years must have been perfect for wax and paper caps and some how the electrolytic caps didn't un-form. Again, a total mystery.
I've purchased all of the replacement caps and will do the swap eventually but continue to enjoy listening to this grand old lady in her 65 year old original glory.
Chris[/i]
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Not that I'd trust farther than I could throw it. ;)
All need restoration - some live on borrowed time, most need it.
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I can think quickly of two of my Philco sets that needed no rebuild when I got them (the WHEN) is the key here!
First, my 112 came from an AWA convention about 15 years ago. It's pretty close to as-new, and I carefully fired it up, fully expecting filters to be gone, or something like that. Not so; the set took off and played like new. It'll someday get new filters, if nothing else, and a line fuse.
Second, my 42-400. Bought it from friends; the original owners. It's the first radio I ever heard FM on, and that was back during the war. Bought the set from them when they were done using it, and it worked flawlessly. That was 1948. O.K., it does need re-cap now, but the original question didn't restrict me on date or age acquired!!!! They replaced it with a TV combination 49-1076.
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