Found in documentation from the 1970s, this circuit uses an oscillator and a display to warn of speeding. The circuit applies to cars with contact breaker.
This two-transistor circuit is from a Radio Electronics magazine from April 1965. The transistors are...
This low power circuit for the FM band was found in a spy book from the 90s. The tunnel diode is...
We found this circuit in a Gernsback documentation from 1960. The circuit is intended for...