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This might be a long shot on this forum, but I’ve got an old shortwave radio with tubes, and I’d like to power it to try it out.

How do I determine what is the input source it expects? The input wires are kaputt and they look like they had been wrapped around a battery terminal. It is hard to say for sure.

What were those plugged into normally? A crank? 110V AC? How can I tell?

I don’t have a model number or manufacturer, but the headphones that come with it are made in Montreal, Canada.

front view

enter image description here

enter image description here

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    \$\begingroup\$ Start by identifying the tubes, and which pins on the tube sockets any of the supply wires goes to, and then you'll have a solid start. \$\endgroup\$
    – hobbs
    Apr 29, 2023 at 6:36
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    \$\begingroup\$ You should also look on the bottom of the chassis and see if there are electrolytic capacitors with voltage ratings. They will probably need to be replaced, but the voltages may give a clue to the voltage(s) required. It does look like it is battery powered, in which case it may have had a fairly high voltage (90 V?) "B" battery for the B+ plate supply, and another low voltage battery for the filaments. Looks to be an interesting antique in very nice condition. \$\endgroup\$
    – PStechPaul
    Apr 29, 2023 at 7:12
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    \$\begingroup\$ I'd add that you should find a good radio club. There are one or two of them in NYC, for example. Contact them. Let them help you do this right. \$\endgroup\$ Apr 29, 2023 at 10:47
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    \$\begingroup\$ Two types of batteries often powered these radios: A-battery (for tube filaments) and B-battery (for plate DC supply). Battery (perhaps more-than-one each) connection points we can't guess. Some of those connection points may be for the antenna wire and antenna ground. \$\endgroup\$
    – glen_geek
    Apr 29, 2023 at 11:45
  • \$\begingroup\$ You have to find out the types of valves used, then you have the datasheets for them. You should read the datasheets very carefully to find out the voltages and currents needed for heating the cathodes of the tubes, too much current will destroy the heating filament, too small heating current prohibits any current from cathode to anode. The anodes voltages are less critical, some volts more or less are no problem. \$\endgroup\$
    – Uwe
    Apr 29, 2023 at 15:38

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I have found THIS on RadioElec: enter image description here

As you can see, there are multiple voltages going up to 120V, but chances are you need 2 or 3 of them, not all of them, and possibly not over 80V.
You would need to take a high-resolution picture of the bottom of the board so that we can try and figure out what goes where and guess the voltages.

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