This audio mixer was found in an old American documentation. The potentiometers are 1M and the input capacitors are 100 nF. The circuit requires power supply voltages from12 to 18 V.
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...