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.
The time constant of this circuit is 100 x R1 x C1, which leads to the possibility of obtaining times...
This circuit with a double-gate MOS transistor was found in a Popular Electronics from the 90's....
We found this circuit in the 1994 Linear Applications Handbook from National Semiconductor. The...