Gerry O’Hara wrote:
I have no idea Ed, but it is a nice design. Are there any manufacturers names on any of the components? Have you had it working?
I will power it up in the next couple days. The only worry may be a leaky phone condenser by Signal depending on its construction. Other parts are tube sockets by King, audio interstage by Amertran, rheostat by Klosner, Fil-Ko-Stat by DX Instruments and knobs by Accuratune. No markings on the variable caps.
It is probably a homebrew. The parts used are high quality, for instance the variable grid leak is mounted on a stamped brass bracket that is held in place by one of the connecting grid thumbnut on the tube base.
The surprise is the Eveready "C" battery. Handwritten on it is "cash, 36 cents, 16-3-1932" For fun I put a digital meter on it. The 4.5 volt section measures 4.2 volts and the 3 volt section 2.9 volts.
I will post further when I fire it up.