This Linear Technology circuit can measure currents from 100 pA to 100 uA. The circuit is from the 80's, using a component of the era. Transistors are general purpose types.
We found this precise crystal oscillator for the 144 MHz band, depending on the crystal used. The...
We found this circuit in a 1967 El3ectronics World. The transistors are from the era but can be...
This circuit open and close the relay in intervals adjusted by the potentiometers. The capacitors...