We found this micro amplifier in a technical documentation from National Semiconductor. The circuit can be used on an experimental phone, being powered even by alternative power sources.
The circuit shown was suggested by Analog Devices (www.analog.com) in its Application Note AN-411...
We found this circuit in Radio Electronics magazine from January 1958. It uses a neon lamp as the...
This circuit has two high-impedance inputs. The gain is high and more inputs can be added. Use a...