11 Sept 2015

Simple 28MHz WSPR (or PSK31) RX

Facebook is throwing up memories from 3 years ago and one of these was a schematic for my WSPR RX for 10m, using low cost 14.060MHz crystals with a Polyakov mixer (injection at half signal frequency) The circuit worked well and could also be used for PSK31. Essentially this is a direct conversion receiver, but it mattered not. Even if you bought all parts new it is very inexpensive.  3 years later I would replace the 2 diodes by Schottky ones as these are now low cost and need less injection than the silicon ones shown.

1 comment:

Jan, OZ9QV said...

I like the subharmonic (Polyakov) mixer - simple in use, as long as you set the oscillator amplitude correctly. No square waves, or it will not work.

Has been used with a 5.0688 Xtal oscillator for receiving QRSS on 10.140 MHz.

When I get my shack in order I am thinking of using this for a multi band QRSS receiver.
73 de Jan