Stephen, I use 110/220V selector switches which you might see on the back of a PC powersupply or HP test equipment. The first in the list:
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available from a multitude of sources. The second item I would prefer over twisted wires. As far as keyed switches, have you ever locked your keys in the car, or misplaced them? Get to the launch site and no key. There's not a fun thought. We dropped an allen wrench in the dirt and it quickly became invisible. Some sifting turned it up, but I'm fond of the 'everybody has a screwdriver with them' method of arming anything.
Joel. phx
What do you guys do to arm your electronics. Do you use key switches? If you
> do what type. Do you twist wires? Do you use another type of switch? Please
> elaborate.
>
> --
> Stephen Corban