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  #1  
Old 05-07-2023, 06:24 PM
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Electronic M Electronic M is offline
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Most radios that didn't have a loop antenna (pretty sure the resistance cord sets predated this) expect roughly a 100' longwire antenna to work correctly.

If you have strong local stations and only care about the locals sometimes you can get away with 6'-30' or wire and or a loop antenna off a newer radio.
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  #2  
Old 05-07-2023, 06:28 PM
fumplet fumplet is offline
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yeah the instructions just say one can coil up the antenna wire and put it inside the set so I dont know if radio has more issues or I just need more wire which I was adding wire up to about 8 feet and then no more gain.
This weird reed speaker really does sound like junk.
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  #3  
Old 05-07-2023, 07:18 PM
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Quote:
Originally Posted by fumplet View Post
yeah the instructions just say one can coil up the antenna wire and put it inside the set so I dont know if radio has more issues or I just need more wire which I was adding wire up to about 8 feet and then no more gain.
This weird reed speaker really does sound like junk.
Some early table radios (late 1930s-'40s) had an external wire antenna and a resistance line cord. The "resistor" in the line cord was a length of wire, which caused the cord to become very warm when the radio was on; the cord had to be placed so that it did not contact anything flammable. My grandmother had one of these radios, a Sears Silvertone table set, years ago in her summer cottage; it worked well, but it overloaded like crazy on one local radio station. The station was a 50kW flamethrower, and the transmitter was just a mile or less from the cottage. I am amazed to this day the sheer strength of its signal did not keep lights on in the place, as 50kW AM stations often did years ago.

My grandmother died some time in the 1980s, and the cottage was torn down shortly thereafter. I wish she would have held on to that radio, as it would have been a collectors' item today.

BTW, I wouldn't coil up any resistance line cord as it becomes very warm, even hot (!), when the device it is connected to is operating.(This is why these cords are often referred to as "curtain burners.")This can and will cause a fire if the cord is anywhere near anything flammable, as I mentioned. The other reason these cords must not be coiled or pinched under anything is the cord can and will become very hot where it is pinched/coiled, causing the resistance wire to open in a very short time. The length of these cords is carefully calculated when the device they are used with is manufactured; lengthening or shortening the cord will alter the value of the built-in line cord resistor, possibly damaging the tubes or other parts of the device in short order.
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Last edited by Jeffhs; 05-07-2023 at 07:59 PM.
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  #4  
Old 05-07-2023, 07:24 PM
fumplet fumplet is offline
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Line cord went missing from previous owners anyway but I did see what was left of it snipped off at chassis. resistance wire wound around a core. I have one other curtain burner radio, a montgomery wards airline? has a ballast resistor on the backside of it that gets smokin hot when running. Still on the hunt for low volume.. Is it the radio, me, the radio stations, or a combo of all 3 or 4 or 5 issues. Voltage checks next as the schematic lists a few to check. As far as the reed speaker Im not even sure I wanna touch it.
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  #5  
Old 05-07-2023, 07:27 PM
old_coot88 old_coot88 is offline
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Does the speaker use a field coil, or permanent magnet?
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  #6  
Old 05-07-2023, 07:57 PM
dieseljeep dieseljeep is offline
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Quote:
Originally Posted by old_coot88 View Post
Does the speaker use a field coil, or permanent magnet?
The thing uses a permanent magnet speaker, referred to as a magnetic speaker, such as the early RCA "tapestry" speaker. Farm radios generally used them, even Zenith. It doesn't use an output transformer.
It's best to see schematic. It has a choke in power supply.
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  #7  
Old 05-08-2023, 08:39 AM
fumplet fumplet is offline
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Quote:
Originally Posted by old_coot88 View Post
Does the speaker use a field coil, or permanent magnet?
It has a horse shoe magnet or at least i think it is a magnet. and only one coil. I think the b+ goes through it. There is a single rod attatched to the cone sandwiched between inner and outer cone shaped washer. This rod goes to I think a flat piece of metal that sits inside this coil. This rod from the speaker is rather small about the thickness of a 32nd. I dont know if I should attempt to remove or dissassemble this speaker yet. Should just post a photo but not sure how to do that yet either.
.

Last edited by fumplet; 05-08-2023 at 08:47 AM.
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Old 05-07-2023, 08:10 PM
dieseljeep dieseljeep is offline
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Quote:
Originally Posted by fumplet View Post
yeah the instructions just say one can coil up the antenna wire and put it inside the set so I dont know if radio has more issues or I just need more wire which I was adding wire up to about 8 feet and then no more gain.
This weird reed speaker really does sound like junk.
I think those instructions are for moving the radio around! When operating, it should be unwound for the entire length of the wire.
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