In the figure we have the way to use the transistors of an old-paired pair as a trigger circuit. The circuit is by Philips from an old documentation.
This circuit can source up to 1,000 V from a 9 V battery. Output current is very low, some...
This circuit detects the presence of strong signals from spy transmitters, enabling their...
This circuit of a publication from the 70's uses a different type of power that we had already...