MY WORK::Restore the ATWATER KENT MODEL 10C BREADBOARD RADIO in 1924

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I did some almost whimsical shopping. On eBay, I saw a radio ATWATER KENT MODEL 10C BREADBOARD RADIO. I bought this radio because I wanted to listen to some sounds on this radio. Since this radio has a circuit to drive the horn speaker, I also purchased a horn speaker made by the same manufacturer.
This radio employs a structure in which an electronic module is screwed onto a breadboard for stretching bread dough and wired behind. That's why the breadboard radio is named. The width of this radio is about 750mm, which is quite wide. The height of the horn speaker is relatively high, about 500 mm, so it seems that it will be difficult to place it.
When I received the radio I purchased, I found that it needed some repair due to disconnection. The vacuum tube UX-201A was bundled with it, and none of the five tubes broke.

This radio has a three-stage tuning circuit. The connection between the coil of the tuning circuit in the first stage (upper photo) and the variable capacitor (lower photo) was broken.

Then, in addition, the horn speaker also had a broken wire that seemed to have a fuse.

It took some time to repair. The reason for this is that the lead wire at that time had an enamel core and could not be soldered unless the enamel paint was removed with sandpaper. It took me a long time to notice this.
Next, you need a power supply to sound this radio. At that time, it seems that it was used with battery power. At the moment, it is difficult to obtain this battery device, so I made a power supply device by combining SW power supplies. Four types of voltage are required: DC5V (for vacuum tube heater), DC22.5V, DC48V, DC27.5V (for AM transmitter). I made it by combining one 5V SW power supply and three 24V SW power supplies.

I'd like to repair these, play an AM broadcast program, and go for a test, but my room is a room in an apartment, and the radio waves of the AM broadcast hardly come in, so I can't hear anything. For this reason, I purchased a self-made kit for the AM transmitter (https://www.marutsu.co.jp/pc/i/1345494/) and confirmed that sound was output via the AM transmitter.

However, this AM transmitter requires as many as three expensive 9V (006P) batteries, so I decided to take power from the SW power supply, including the heater power supply for the vacuum tube 12AU7.

At last, the restoration was completed and I was able to listen to it. At that time, I was playing a song from the 1920s that was in the public domain or royalty-free.
Well, I'm a little worried about noise, but I was able to confirm that it works as an AM radio.

The AM transmitter is equipped with a connector that is supplied from an external power source instead of a battery, and then stored in a case so that it can be placed vertically.

And I secured a place to put it. Somehow, I emptied the shelves so that I could put a set. Now you can hear the sound at any time.

The sound source of this site may be good for the music you listen to on this radio. There is also music from the same era as this radio.
Free Music Archive: Old-Time / Historic
that's all.

[TRIAL AND ERROR]