5874E)
This circuit uses an optocoupler to switch a load on the power grid. The circuit is from Electronics Now magazine, July 1995. The CA3059 is not common today.
This voltmeter has an input resistance of 200 M ohms (47 M ohms resistors can be used in series to...
We found this circuit in an old documentation, but the components used offer no difficulty in obtaining...
This old 1967 audio preamp uses germanium transistors. It was found in Japanese documentation at...