This circuit identifies the polarity of DC signals and if the signal is AC. The circuit is from 1969 US EDN documentation. Operational may be equivalent.
This circuit consists of a power audio amplifier used in the modulation of AM transmitters. The...
Two or more 4013 can be cascaded to perform a divide-by-4 (-8, -16, etc.) as shown here. The...
Using an integrated circuit from the time, this circuit was found in Radio Electronics from the...