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 circuit from Radio Electronics from February 1983 shows how to use a clock radio in home...
With this converter it is possible to tune the signals of the 15 MHz WWV.in AM receiver. WWV is...
This variable frequency oscillator generates signals that have a recurrence frequency determined by...