Friday, May 20, 2011

The 50MHz RX "MINIMALIST"

Fits like a tone control transmitter, frequency meter...

2 comments:

coffeeCup9NZ said...

what is the function of the two diodes back to back?

Calvin said...

This is a direct conversion receiver using a Polyakov detector (the two anti-parallel diodes)... The third harmonic of the 8.362 MHz crystal is exactly half of the frequency of interest and mixes with the incoming rf to give a baseband output to the crystal earpiece... Google "polyakov direct conversion receiver" to learn more...
8.362