Found in na 1970 EDN this circuit has a parallel regulation providing a symmetrical output of 15 V. The transistors are from that time.
The purpose of this 2000 documentation circuit is to decode SSB (BLU) signals to be audible on...
This circuit was found in a Popular Electronics of the 1980s. The microammeter may be the lowest...
This high selectivity circuit for single tone decoding was found in 1970s documentation. The coil...