This dual-gate FET RF signal mixer circuit was found in a 1980s documentation. The circuit is intended for applications in superheterodyne receivers of the time.
We found this oscillator that operates on the third overtone in a 1975 amateur radio...
This complete single cell protection system is suggested by Linear Technology in its 2005 manual....
Using an RCA integrated circuit, this instrumentation amplifier was found in a November 1970 Radio...