This circuit was found in a 80s American documentation. The zener diodes determine the points of action of each stage and the transistors can be general purpose types.
This circuit was obtained in a 1982 English magazine. The purpose of this circuit is to make an...
This is a change from the previous interface, also used an uncommon operational one today. The...
This circuit uses a capacitor to momentarily reduce the anode-to-cathode voltage of the SCR for...