We found this circuit in the October 1988 Radio Electronics magazine. The circuit is still current due to the components used, and changes can be made.
This circuit is recommended for alarm systems since it has a good output stage. The circuit is...
) Suggested by Philips in a 1968 documentation this circuit has very high 10 ohm on-load voltage...
No information is given about the transformers in this circuit suggested by Motorola in a 1968...