We found this circuit with transistors in a Philips documentation from 1968. The double transistor can be replaced by discrete married types. The power supply is symmetrical.
This circuit for the 1750 m band was published in the September 1989 Radio Electronics magazine. The...
The purpose of this circuit is to disconnect the battery in case of an excessive charge current,...
This circuit was originally designed to operate with the alarm CIR12065 which has a tone output. It...