This converter has coils according to the reception and converted frequency bands. We found it in the October 1989 Radio Electronics magazine in an article that teaches its construction.
This circuit can be used as a rhythmic light or as a control shield for incandescent lamps from...
We found this circuit in a European publication from the 1990s. Transistors are still common types...
Settings like this can be found in this section and on this website, but from different sources of...