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Originally Posted by steve gibson
My wife picked this up at a garage sale for 25 bucks. Everything is there and in excellent condition. Not working at present- short somewhere but all tubes are ok. I have spent the better part of a day trying to find information. I think it is a model 53. I have found a model 52 and 54 listed and they are very similar. Thumbwheel dial, 9 tubes, cool push button unit behind one small door. 2 knobs. Any ideas? I would really like to find a schematic.
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Steve, that radio looks like a 1929 Zenith, one of the first consoles they made with push-button tuning. I saw one like it on one of the antique radio websites. Twenty-five dollars is a very good deal for a set like that; in fact, I think the former owner was a bit too generous as this model is or may be quite rare, and should have gone for a lot more. However, since most people running garage sales know little or nothing about the true value of these radios, you can often find rare antiques priced ridiculously low, high, or even going for next to nothing, depending on how badly the seller wants them out of his or her house. I've never seen one up close, but if your Zenith console is the model I think it is, you have a unit that can fetch a good price on ebay if you can get it working.
I'd look on the antique radio websites such as Phil's Old Radios, et al. for information regarding the schematic; in fact, you may find it at Nostalgia Air (nostalgiaair.org) if you have the exact model and/or chassis number. There used to be a site, called "The Zenith Oracle", dedicated to information on the older Zenith radios; I don't know if it's still around (I don't remember the URL), but if you can find it, it will be another great source of information on the company's now antique broadcast receivers dating back to the '20s. Another way to find the info you're looking for is to do a Google search on "Zenith model 53" (or the chassis number) and see what turns up. You might look on Yahoo for a group specializing in Zenith radios; you never know, you might find a few leads there too. Another source is your local public library; many libraries have files of Sams Photofacts, although trying to find one for a 1929 radio of any make could be frustrating as I don't know if Sams was even around in the 1920s, let alone whether libraries of the period carried such folders.
BTW, if that radio has a short in it, don't plug it directly into an outlet and turn it on. The power supplies in many of these older radios were not fused; a short anywhere in the chassis could damage the power transformer or other components or even start a fire. If you want to plug it in just as a test, use a 60-watt light bulb (the size will depend on the current drawn by the radio) in series with the AC line cord, then plug it in. If the bulb lights dimly, go ahead with your testing; no harm will come to the circuitry. However, if the bulb immediately lights to full brightness and then burns out with a flash like a camera flashbulb as soon as you turn the radio on (or worse, as soon as you plug the cord in the AC outlet), your radio's power supply definitely has a short or other problem which must be corrected before your tests can continue. As a start, I would check the low-voltage rectifier tube for shorts, if there is one; next, check the input filter capacitor in the power supply (if it is shorted it will cause the radio to blow a fuse as soon as it's plugged in); after that, test the power transformer for shorts (however, if you notice that the transformer is running extremely hot, not just warm, after the radio has been on just a short time, the transformer is definitely shorted); and finally, if your Zenith has a field-coil speaker, check the coil for shorts. The field coil is part of the power supply and will overload it if it is shorted. Needless to say, pull the plug in a hurry if anything starts smoking or smells hot in, on or around the chassis! That is another dead giveaway there is a big juicy short somewhere, one that can cause serious damage to the radio if left unchecked. An example: I have a Zenith Transoceanic transistor portable in which the battery case, and the batteries in it, became extremely hot after just a minute or so; the problem turned out to be the AC adapter jack, which was positioned in the cabinet in such a way that it was putting a dead short across the entire battery pack [eight D-size batteries for a total of 12 volts]. The batteries were pumping out as much current as they could deliver to the short; the radio wouldn't play, of course, until I repositioned the jack in the cabinet and insulated it. Now, everything works fine. This is just an example of what a short in a power supply can do in a battery-powered circuit; multiply that by ten or more and you have the effect such a short can have on a high-current AC supply used in a tube-powered radio such as your 1929 Zenith.
Please forgive me if the foregoing sounds elementary, but it is advice I'd give anyone trying to repair and/or restore any kind of vintage or antique radio, TV or electronic gear. I am not trying in any way to insult your intelligence or anything of that sort. I don't know you or how much you know or do not know about electronic servicing, so I'm just offering this advice as a precaution, and out of force of habit.
Good luck and very kind regards,