Portable field radio 5 band DDS QRP (Ukrainian edition)


The schematic of the radio almost like PFR-3A, but for 5 bands with 5 Low Pass Filters and 5 Band Pass Filters and with rotary encoder for freq tuning
IF filter is on 4,9125 MHz
As microcontroller we using Arduino Pro Mini board and LCD0802 as a display
There are two adjustments:
AF – audio freq (volume)
RF – works like attenuator. Some voltage closes transistor between antenna and BPF. Very useful at 40 meters
Tuner is Z-match

 

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