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.