How do you build a BFO for a shortwave Radio?
I was on amazon looking to buy a better shortwave radio and this guy on there said "I did build a separate little circuit called a bfo. When I hold this next to the radio, I can understand radio amateur transmissions (around 7 mHz). " and I would very much like to be able to do the same, So how would you build such a thing. Thank You. All the best.