This amplifier for hearing aid was found in a 1968 documentation using an integrated of the time. The power is from a battery, the consumption of 1.65 mA and the power of about to 1 mW.
Suggested by an American documentation for 1969 neon lamps, this circuit provides SCR control with...
This circuit was obtained in a 1976 amateur radio manual. The circuit can be made with a 2N2222...
This circuit was taken from the 1974 Ferranti transistor manual. It is intended to use a common...