Monostable trigger arrangement

A monostable trigger arrangement comprising:

• a monostable trigger stage for producing an output pulse;
• a bistable switching circuit means having its output connected to said monostable trigger stage, and responsive to a control pulse for switching said bistable switching circuit means from an untriggered state to a triggered state and to an erase pulse for switching same from said triggered state back to said untriggered state, for controlling said monostable trigger stage to release an output pulse only when said switching circuit means is switched to said triggered state, said bistable switching circuit means including a thyristor connected across a pair of voltage supply terminals and having a single gate electrode for receipt of said control and said erase pulses, said thyristor being rendered conductive, and thus switched to said triggered state, in response to a control pulse applied to said gate electrode, and being rendered nonconductive, and thus switched back to the untriggered state, in response to an erase pulse applied to said gate electrode.