Back to Agent Sonya and Her Vacuum Tube Homebrew Rig

How difficult is it to build a single tube ham transmitter? Honestly, I don't know because I haven't tried.

The gang and I are out camping this week and thoroughly enjoyed listening to the latest episode of the Soldersmoke podcast as we were out exploring the area around Baker, NV. In the podcast, (episode 260), Agent Sonya came up again. (Here's the Soldersmoke blog post for the podcast.) I have to say, I'm still a believer. Maybe it's time to put my money where my mouth is though. So, this week, the kids and I will be researching:

The article in the 1936 radio handbook on page 111.
Whether or not we can still get our hands on a functioning 6C6 tube and socket.
Can we find a crystal that fits into a socket like the ones advertised in the back of the handbook?
Can we maybe bring the plate voltage 6A6—aka a 53 tube—down to something more manageable than 450 Volts?
How does the circuit function and how does it depend on plate voltage anyway?
What sort of oscillator does the circuit employ?

Speaking of which, here is the circuit.

In the handbook, the article gives me the impression that a 6A6 and 53 tube are interchangeable. However, looking at the 6A6 datasheet—which cross references the 6N7—I can't find any higher plate voltages than 250 or so.

Looking at the 53 data sheet, I finally found this

More research will be done!

References

Very pretty blog post on the 6A6

Page 23 of the handbook above discusses different types of tube amplifiers.

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