This circuit uses a lamp driven by the Hertz loop and measures its brightness with ordinary photovoltaic cells. The circuit is from a Radio Electronics from February 1964.
The RCA integrated circuit used in this control is uncommon today. The circuit is from an...
We found this circuit in a Popular Electronics of the 90s. The circuit uses a touch sensor formed by...
We found this circuit in a European schematic from the 90s. The used integrated circuit can still...