Found in a 1968 EEE, this circuit uses transistors from that time. The output is 300 ns. Transistors can be replaced with modern equivalents.
This circuit is suitable for low impedance m icrophones. Gain is given by the 2M2 resistor. This...
This sensitive circuit was found in old documentation. The SCR can be any of the 106 series and...
This preamp with several inputs using germanium transistors from the time was found in Japanese...