For signals up to about 500 kHz modulated in amplitude and transmitted by the power network, the figure shows the receiver. The circuit is from a Radio Electronics from February 1989.
The circuit shown is from an old publication, from the 70s, but can be assembled with TIC106 SCRs...
This receiver is from an old English magazine from 1965. The transistors used are germanium, no...
This circuit is from Delco Radio found in a 1968’s documentation. The transistors are of the time...