Test of a DC conversion RX for 40m band
Receiver for 40m HAM band (7.0-7.2 MHz), with direct conversion. This RX uses "harmonic mixer". The frequency of the oscillator is 1/2 of the received frequency and it is doubled in the mixer. This design was popularized by Russian radio-amateur Vladimir Polyakov.
http://599.cz/dc_rx_polyakov.html
Timestamps:
00:00 Title
00:15 Listening to the telegraphy
00:35 Schematics
01:11 Assembled PCB
01:37 Tuning and listening to telegraphy
03:50 Listening to some digital signals
05:00 Listening to SSB voice
09:30 Some AM stations outside the HAM band
09:55 Strong Germany SSB station