In the figure we have the configuration of series regulator protector suggested by Motorola in 1968 documentation. The transistors are of the time, being able to be used modern equivalents.
This circuit was obtained in Motorola documentation from 1969. The components are from that time. In...
We found this circuit in a Poptronics of the 90s. The circuit operates from 100 kHz to 30 MHz and...
We found this amplifier with 50 MΩ input resistance in the May 1989 Radio Electronics magazine. The...