This is the commercial circuit for the TRF-44 amplifier sold in Japan in the 1960s. The circuit provides a few hundred milliwatts and is intended to be used as small, battery-powered turntables.
This circuit of a 1978 American publication monitors a telephone line by triggering a relay. The...
Found in 1965 General Electric technical documentation, this half-wave circuit controls shunt type...
The power supply shown in the figure provides voltages between 0 and approximately 15 volts, with...