Found this on my old HDD. Actually have tried to build this a few years ago but couldn`t get it to work.
1) Does anyone know the specs for SK3126? Couldn`1 find a datasheet anywhere, tried using a normal signal diode first, the 1/2 of BB204(IIRC)
2) BF245 is supposed to be a useable replacement for MPF102, any reason why it wouldn`t work in this circuit?
3) Is the second LC stage a doubler/tripler/whatever or simply a tuned amp?
4) What`s the frequency range this thing could be useable in?
Thx!