This circuit allows the activation of a remote telephone bell made with a common piezoelectric capsule. The circuit does not need power, as it is powered by the line call signal itself.
This circuit is from an American cookbook from 1977. The circuit generates a voltage of...
In the figure we have the simple way to implement the NO-OR or NOR function with common diodes and a...
We found this configuration in an integrated circuits manual. The transistor, which can be of any...