This circuit was found in the January 1999 issue of Electronics Now magazine. The circuit uses an integrated circuit from the period and has earphone listening.
In the figure we have a way of using a solar cell as a source for circuits with tunnel diodes. The solar...
This equalizer was found in the May 1978 issue of Radio Electronics magazine. The component values...
This circuit for high-impedance magnetic headphones was suggested as an experimental amplifier for hearing...