This circuit with a differential pair was found in the August 1974 Radio Electronics magazine. The frequency is determined by L1 and the variable capacitor.
We found this bench circuit in a Radio Electronics magazine from July 1962. The transistors are...
This circuit is from an 80's documentation. The circuit makes use of a component of the era, the...
This Linear Technology circuit can measure currents from 100 pA to 100 uA. The circuit is from the...