This symmetric 30 mA x 15 V power supply was found in the Ferranti transistor manual from 1974. Transistors are common types at the time.
This amplifier with a few watts of power was found in a Japanese technical documentation from the...
This high impedance headphone amplifier was found in American documentation from the 1990s. Any...
This small audio amplifier was found in the May 1994 issue of Electronics Now magazine. The power...