We found this circuit in an old English documentation. Transistors support modern equivalents. The circuit converts signals in the 5 to 15 MHz band for tuning into a common medium wave radio.
Found in na 1970 EDN this circuit has a parallel regulation providing a symmetrical output of 15 V....
This configuration found in a 1976 publication can be elaborated with more modern operational...
This ultra-simple meter uses an output transformer and a small speaker as a microphone. The...