By 1948, Pepperl + Fuchs was expanding into other electronic production, leading to the development of the first proximity switch in 1958 and the first transistor amplifier with an intrinsically safe control circuit.
12.
There may be less power available to maintain flight overall, but the minimum safe control speeds remain the same as they would be for an aircraft being flown at 50 % thrust on all four engines.
13.
Blasting caps are ignited utilizing hand-held intrinsically safe control boxes which employ a series of safety interlocks and switches which require a strict radio sessioning handshake protocol between the unit which ignites the cap and the unit used by the Master Blaster controlling the shot, ensuring that the emplaced Tovex, detonation cord, and caps cannot ignite prematurely.
