Someone posted this on the GloBugs list with another QRP tube rig from the '50's. This one used no transformer, and gained my intrest- and rapidly, that of others. Unlike another one tube wonder (the AC-1) this one no longer has a parent company controlling copyrights to the name. While we could not find the circuit diagram for it, enough information is given for us to deduce a probable way it worked. The circuit diagram below is the result of my efforts to recreate it's circuit. Given the expense and general difficulty in obtaining transformers used for even small tube transmitters, this looked like a winner for a peanut whistle sort of transmitter for the glowbug enthusiast.
The inductance on the PI network should be according to this chart:
| BAND MHZ LOW END | L, uH |
| 3.5 | 22.8 uH |
| 7.0 | 11.4 uH |
| 10.1 | 7.54 uH |
| 14.0 | 3.95 uH |
| 21.0 | 1.78 uH |
NOTE that the 730pFd cap is simply a pair of 365pFd tuning capacitors, in a commonly available 2 gang tuning cap such as is sold by midnight science ( http://www.midnightscience.com/ ) They also sell the single game unit used to tune the plate. Plug in coils and matching 5 pin sockets are available from AntiqueElectronicSupply (TubesandMore.com) AS ARE A GREAT MANY OTHER PARTS OLD AND NEW AT MILDLY STIFF BUT NOT OUTRAGIOUS PRICES- AND THEY HAVE A lot OF STUFF AVAILABLE. I do business with them fairly regularly.