Category Archives: Broadcast breakthrough

Second order Butterworth BPF

I decided that the broadcast breakthrough was just too strong to live with for my little direct conversion rig, Mrad-40.  I’d made a band pass filter (BPF) already, but it’s roll-off wasn’t stiff enough to knock down shortwave broadcasts, especially … Continue reading

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Fixing some wiring mistakes

  The little Mrad-40 is really blasting audio now — now that I’ve fixed two major wiring errors! The audio now is too loud for headphones and can power a small speaker.  But I’m using the amplified speaker anyway just … Continue reading

Posted in Broadcast breakthrough, direct conversion, Mrad-40 | Leave a comment