Found in a QST magazine from the 90s, this circuit broadcasts on different amateur radio bands depending on the coil. Data for the coil and crystal are provided next to the diagram.
This is Heathkit's CW-30, a miniaturized 4-transistor receiver for the citizen band or 11 meters. The...
I found this circuit in a Lujy 1962 English magazine. The circuit is still viable by simply using a...
Found in a Popular Electronics from the 90's, this circuit is used to indicate the operation of...