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.
This 1987 circuit uses a common ignition coil to generate high voltage to power a fluorescent lamp that...
This circuit is from the American magazine that no longer exists Science & Electronics,...
This circuit is from a 1975 technical documentation on filters. The FET can be a BF245 and the...