This circuit, obtained from old documentation, doubles the frequency of the pulses applied to the input. The circuit must be powered by a voltage of 5 V.
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...