This MOSFET circuit for microphone applications was found in the December 1969 issue of Radio Electronics magazine. The transistors are uncommon today.
We found this simple transistor tester in a French publication in 1981. It uses a common analog...
This circuit was found in the September 1984 issue of Radio Electronics magazine. The circuit is...
We found this circuit in Ferranti's 1974 transistor manual. The components are from the period. Note...