This circuit was found in a 90s Popular Electronics. It produces a muted tone similar to that produced by a bell. The signal must be applied to an amplifier.
The circuit in the figure uses the four current amplifiers of the LM3900 to generate a sawtooth signal...
The presented circuit was suggested by the 1994 Linear Applications Handbook from National...
This circuit was found in a Motorola documentation from 1968. The load current is 10 A. The...