This circuit was found in Motorola's 1967 documentation. The circuit makes use of power transistors of the time. For pulse pickup an appropriate pickup coil is used.
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...