Voice powered transatlantic 20m test

AA1TJ's historic attempt to span the Atlantic with just a "voice powered" TX (powered only with DC generated by rectifying audio from a LS into which he was shouting) started at 1500 UTC on Tuesday Nov 10th. Power out was about 15mW QRP from the coast of Maine, USA. They had a 2el vertical antenna aimed at Europe and a good clear sea path, but unfortunately the test was unsuccessful, although they did make contact (not voice powered though) with Europe on 160m QRP. For a report see http://www.QRPme.com .

AA1TJ's "Code Talker TX" - all voice powered

Mike Rainey continues his work on purely voice powered transmitters, in which just the energy in his voice is used to power the RF circuits i.e. no batteries or PSUs at all. He's achieved well over 100kms on 80m this way using a form of CW derived by whistling into a loudspeaker to generate the energy needed. Here is an example of his signal received 109kms away. He can clearly be heard "keying" (actually whistling!) the words of "Mary had a little lamb" in CW.

161kms voice powered QSO by AA1TJ

Just got an email from Mike Rainey AA1TJ describing his TX powered only by his voice. He achieved a distance of 161kms with a germanium transistor oscillator putting out a few mW of power. The power for this was generated by rectifying the audio signal from the loudspeaker used as a microphone. In the end Mike resorted to a sort of MCW mode shouting CW into the LS but W1VZR copied this and made a recording. Mike is also looking at a receiver using "RF harvesting" to allow a receiver that requires no DC power source other than that derived from off-air RF.

Mike's amateur radio pages are at http://mjrainey.googlepages.com/radio