This circuit with two transistors was found in ancient European documentation. Transistors support equivalents. The indicator on this circuit is an ordinary 50 to 100 mA lamp.
We found this circuit in the June 1992 issue of Radio Electronics magazine. The sensor is a common...
This circuit converts a positive CMOS supply voltage to a negative one. We found it in a 90s...
This tone control was obtained from the CA3140 datasheet, originally created by RCA. The CA3140...