The circuit presented is a Japanese commercial radio for AM with 50 mW of output power, powered by 9 V. The circuit is from the 60s, having been found in documentation of the time.
The circuit in the figure uses the four current amplifiers of the LM3900 to generate a sawtooth signal...
This circuit was found in an old Motorola documentation from the 70s, as it uses one of its...
This circuit for an optical audio link using LED or LASER was found in a 90s QST magazine. The circuit...