This amplifier uses a 1975 integrated circuit, which is uncommon today. The circuit has a gain of 30 dB and uses a transformer-less output with 9 V power.
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...