This circuit was obtained in a Popular Electronics of the 90s. The circuit uses integrated from the time, uncommon today. Note that the speaker has a higher impedance than ordinary speakers.
The integrated circuit used in this project is not common today, but the circuit can be adapted to use a...
This low current source without a transformer is intended for applications where insulation is not...
This dimmer for high-powered incandescent lamps was found in a 1967 General Electric manual. The...