I'd like to see if this radio works. It's not an original, I'm told, my car was a radio delete, but it looks good in the dash. There are two pieces to it, connected by silver braided cables. The only two electrical connectors I have seen are the yellow and gray wires coming out, and they are twisted together and not connected to anything. Anyone familiar with a radio like this? If it powers up will the tubes glow or something? There is no speaker hooked up, no idea where those outputs are.
A guy gave me a radio for my '51 Ford a few years ago. He had it in his garage and was going to throw it away. It was the correct DeLuxe (8 tube) radio for the car, so I accepted it. I installed it and guess what? It didn't work. I had an "Ace up my sleeve" however, as my best friend is an "electronical genius" who cut his teeth on these things.. What I found out from him is that it is not the tubes that go bad, but the old paper and foil capacitors. He finally got it fixed (with all of the original tubes) by replacing all of the capacitors with new units, and installing a solid state vibrator. The result? It worked great if you liked crop reports and foreign language news stations. Save yourself a lot of time and money, and either leave it alone or convert it to modern guts so you can get FM and even play stuff from your phone.
Generally it is the electrolytic filter capacitors that need to be reeplaced, not paper in oil caps, which shouldn't have to be replaced unless they become leaky (electrically leaky, leaking DC onto the signal path). Sorry I can't help you with your questions, not familiar enough with car radios. Typically tube amplified radios need to have a speaker load attached whenever the radio is powered on. There should be an output transformer to transform the high impedance output from the tubes into a low impedance for the speaker (4 - 8 ohms probably). So don't hook it up if you don't have a functioning speaker attached. Also, those dried up electrolytic caps I mentioned above, they can arc and explode making a bit of a mess, so I wouldn't try powering it up if I were you. I'd get it to somebody who knows those radios and let them go through it first.
DONT STICK YOUR FINGERS IN THE CAP BANK...... If you never had any experience with tube equipment let some one else do it..
Right at the end of the tube era they used (somewhat) better blocking and coupling capacitors. But the older style waxed capacitors made of paper & foil should be replaced. The electrolytic power supply capacitors are always toast. The high value 1M ohm resistors are often defective by now, and unfortunately even the silver-mica capacitors are showing their age. I wouldn't mess with those unless the radio doesn't work, or work very well, when you're done replacing the power supply and coupling caps. The tubes are pretty tough, but they will get smoked with a defective power supply. There is a "vibrator" and buffer capacitor as part of a car radio power supply that will need attention. Btw you might not see many or even any of those tubes glow due to their construction and the "getter", the silvery stuff on the inside of the tube.
Don't power it up with any unknown wires left open or short circuited, you make permanently kill the radio. The tubes' heaters will glow when working., but may be hard to see. If you have a Ham radio club in your area, a lot of these blokes started fooling around with this stuff when they were pups. Someone there may be able to help you with a repair. There is a multitude of things which go bad in valve (tube) equipment, as mentioned, condensors (capacitors), resistors, transformers, valve sockets, etc., but they sound great when working well!
I might have a match to that radio, I’ve one that has the same knobs on it. I’ll look for it this weekend. If it’s the same as yours you can have it. Might work, or have parts you can use in it.
My dad repaired TV's and radios as his hobby in the tube days...Remember him going to the drugstore to use their tube tester until mom gave him one for Xmas....
I remember doing that with my dad, that's probably how I get the bug. I recall he would pick up a sheet of numbered stickers, with 2 of each number. Then he'd take the back of the tv set and apply 1 of the numbers to a tube, and stick the matching number onto the socket. Then he'd do that for the rest of the tubes, and put them all in a paper sack and take them down to the local drug store (Thrifty Drugs, probably some So Cal guys remember that chain) put them one at a time in the machine and test them. Those that failed were replaced from a rack of tubes above the tester. I even did this myself with my first tube guitar amp back in about probably 75, the machine was still set up in the Thrifty Drugs, and the replacement tubes still there. Damn, those were the days. I still have that guitar amp, I even posted about it in the Antiquated. I too now have a tube tester, which I use for the tube guitar amps I work on. It's not nearly as good as those machines they had in the drug store, but it does help to have it sometimes.
Televisions ran certain tubes really hard, especially Color TVs. The horizontal sweep tubes, or something like that. They wore out quick. Radios and stereos, many of the tubes lasted thousands of hours. Rectifiers and audio outputs not so much. That's why some of them have reached Arm & Leg price status. The story I heard, was the "U-Chek-It" testers at the drug store were often adjusted or calibrated to falsely indicate a given tube was a bit on the weak side - in order to sell more tubes. The most important tube test is a tester that is accurate for finding internal shorts, the thing with vacuum tubes is they may be "weak" but will work perfectly fine for years depending on the circuit. A vacuum tube may also test "good" on a tube tester and not work in a particular circuit. But a tube with internal shorts should always be discarded. More sophisticated tube testers also employed a "mutual conductance" test that more realistically determined whether a tube would actually work. Most times, replacing tubes in a radio is not necessary and a waste of money.
Get it to a tech that can inspect it and put it on an oscilloscope. I have one for amplifier repair and biasing vacuum tubes but don't really use it. My tube equipment is currently in good condition. As stated, the power capacitors need to replaced, at a minimum if it has any age on it at all. It's a cheap fix if you can find an honest tech. Joe
I've got an old tube console stereo at home that has the stereo and record player in it and I just loved the mello sound it put out. A couple years ago it started were it would warm up and then the sound would start fading in and out. I figured its probably a weak tube but I never pulled it apart to check. All this talk about tubes I think it might make a good winter project. I do miss and love the sounds it had..
"Probably just needs a Tube" Yeah no, that is hardly ever what they need! Replace those power supply electrolytics. They had an intended lifespan of maybe 10 years or so.
I can tell you a couple of things about it from the size of some of the components I see. The big tubes are the audio output tubes and are probably 5881's which 2 of are rated at over 50 watts of audio out. The size of some of the wiring is another giveaway to lots of booming audio. The large size of transformers is another clue. When working at normal listening volume, the system will be a current hog probably taking 20 amps just idling. It should really sound good though if you use quality speakers. A real bass thumper. One thing though, it is going to be expensive if you have to do any repairs or restoration.
radio bill posted above. You may want to check him out here: https://www.jalopyjournal.com/forum/threads/am-fm-radio-conversion-w-aux-in.1002575/ He was polite enough to not promote himself.
I once re-tubed a Bogen J50 amp with NOS tubes. As much to preserve the originals as anything else. It was not hard to find all mid 50's American tubes for it. They weren't that expensive either, considering. Try the tube numbers at these places: https://tubedepot.com/ https://www.thetubestore.com/ https://vacuumtubesinc.com/ As has been said, you will likely need to re-cap it. That's harder (think soldering), but not too spendy either. Some of the above tube vendors have caps too. I found a parts manual reprint on Ebay that had the cap list in it. Big help, ID'ing what you need from what you have can be tough. If you have the values, there are a bunch of electronic sources. If you dive in and do it yourself it's fun and educational. And a bitch. If you have it restored, get your wallet out. It is labor intensive. Good luck ! Mike
Yeah, a really great way to destroy vacuum tubes (and $$& transformers) is to plug it in and "see if it works" or, continue to operate it with a defective power supply (electrolytic capacitors). The high voltage power supply is basically made up of the Rectifier and those large silver "cans". This is always the Achilles Heel of vintage equipment. Most vacuum tubes themselves are pretty tough and long lived, within their voltage limits. They even used vacuum tubes in proximity fuses for artillery rounds. But they will be quickly roasted without a "Tune-Up". A fresh power supply will almost always get the unit going again reliably and safely. Be careful, tube gear has lethal voltages therein, it will bite you!
You cheated and only showed the "Good" side! Flip that chassis over and see where the real wiring is done! As Mike said, tubes are available, new and used. I found a tube tester, and hundreds of tubes, learnt how to test them, and am slowly converting them into car parts!
For some beginner tips and tricks as well as in depth restoration of vintage or classic Radio, Television, & Audio gear etc it would be pretty tough to improve on https://www.antiqueradio.org/
I had heard of the website you referred to but had never been there. I enjoyed reading about the SX42 restoration. Kind of reminded me of replacing the screen by pass ring on a 4-250 socket in a KWS1. I haven't done any in the last couple years but for many years restoring old radios was a favorite winter project when there was no racing going on.
I can tell one of you guys is itching for me to send you this for a HAMB tech thread. So I just removed it. Dang thing weighs 10lbs.! I think the front of the car went up 1/2". So what's next? I guess I should at least put some juice to it. There's the two yellow and gray wires coming out of the radio, and two wires coming out of the transformer (?) on the tube unit. Would those be speaker?
The larger of the 2 transformers is the power transformer, the smaller upright mounted one is the output transformer, the gray wires coming from that are the speaker wires. You did read @Truck64 's comment about rebuilding the power supply before trying to fire it up, right? If those electrolytics are dried out, and they probably are, you might get a big flash when you plug it in. Or, you might just get a loud hum. It's usually best to replace the caps first before applying power to an old amp that's been sitting for years. Some guys try to "reform" them by bringing them up slowly with a variac. I've never attempted it, I just replace them.
Yes, the brown ones should have the value printed on the case somewhere, the metal can will have probably 3 - 4 caps inside of it and the values (capacitance & voltage) should be stamped on the case. The individual caps are fairly easy to find, a multi-cap can with all of the correct values is harder to find, but you can use individual caps in place of it. I've even gotten creative and opened up & gutted the can and stuffed with new caps of the correct values when I wanted to maintain the appearance. I've seen others post links to some sources above, I didn't see this one: https://www.tubesandmore.com/ Or this one: https://www.mouser.com/
OK thanks Blues. Not seeing many numbers but I'll leave it on the bench for awhile and see how inspired I get. A lot of options for aftermarket radios. I'm not that big on car audio, just thought as long as it was there.
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