Found in American documentation from the 90s, this circuit uses common FETs. It has a range drift sensitivity adjustment.
This twisted pair exciter circuit uses 80's components. The circuit is from a documentation of the time, but...
Based on Radio Shack 276-137, this circuit was found in the December 1995 issue of Electronics Now magazine....
Placed near a telegraphic transmitter (CW) and with a small antenna or pickup, it reproduces the...