30 Jan 2010

AA1TJ's success with the XBM80-2

Mike Rainey AA1TJ has built his version of the XBM80-2, but LESS the audio stage, using instead his 600 ohm magnetic headphones via a transformer, and has managed some QSOs well over 100 miles. He changed the emitter resistor to 15k to reduce the signal radiated on key-up (backwave) as well as made a link coupled bandpass filter output/input circuit. This would reduce the amount of AM breakthrough usefully.

1 comment:

Ham Radio Accessories said...

I appreciate update on AA1TJ.