Subminiature Tube Superheterodyne Radio

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This is my first homemade superheterodyne radio, and the first radio I've built that works! The circuit is based on an AA5 (All American 5) and WA2ISE's modifications. Most of the parts were strapped off an old AA5 Motorola radio. Some other parts came out of my junk pile. Below is the schematic diagram of my radio.

I had several issues with the power supply design, since I did not have some of the tubes. Therefore, the 145VDC B+ supply was separate and the tubes' filaments ran in series from a 25V transformer.

If the oscillator coil does not oscillate, then reverse the connections on one of the coils. Some oscillator coils may have only four terminals (two coils), so use a 56pF capacitor from the grid of the 6111 and the oscillator coil (see schematic below).

For the power output tube, a 5902 is recommended for more power. I didn't have that tube so I used a 5702 instead. Also make sure the speaker is a reasonable size so it doesn't draw too much power, or the output tube may get stressed.

Pictures of my homemade subminiature tube superheterodyne radio:

Subminiature tube radio

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