Found in a 90s Electronics Engineering, this circuit makes use of components of the time. The critical component is the microwave sensor diode.
This multiple switching power supply was found in the April 1991 issue of Radio Electronics...
This circuit makes the simple test of SCRs that have a low maintenance current, with those of the...
Some old multimeters have a high resistance scale that has an internal circuit powered by a 22.5 V...