A safety tip I'll add;  Shorting the firing leads except when launch
is imminent isn't a bad idea.

  Also: You can use a pair of big 3PDT switches, wired with an
appropriate flashlight bulb (or buzzer) and a resistor, so that in safe
mode, the input wires are across the bulb/buzzer, and the output wires
are connected together, through that resistor, to reduce any chance of
static or induced RF currents;  In "Fire" mode, it's just a
straight-through connection from the controls to the launch pad.

  Put one or even two of these in series (Set one 10 feet away from the
control station, one 10 feet from the rocket launchpad) is an safety
trick that I like (The 1k resistor can be a short, I've heard arguments
re: RF transmissions as to which is safer, but not kept up on that;
Twisted pair wire isn't a bad idea if you do use a short.  Probably
pretty safe either way, so long as your wires are kept close together!)

  As you walk down range, with safety key in your hand, you flip the one
& then the other safety to "Safe" and then continue.  Hard to get an
accidental launch this way!  Then as you walk back to the launch
console, you flip each to "Fire" as you pass.  AGAIN, do not flip the
circuit to "Fire" if the light bulb there is lit or the buzzer's
buzzing, as that's a really bad sign <G>

  I sketched this for a guy who had a blasting permit and had some idiot
handle his blasting box while he was putting in 30 pounds or so of ANFO
explosives to blow a big stump; His has LOUD buzzers so he knows when to
panic <G>  It's not a bad design for model rocketry; maybe a little
over-paranoid to use two, but one of these set to "Safe", 10 feet away
from a Multi-F engine cluster would make ME for one a lot less paranoid
about sticking my face in close to examine the ni-chrome ignitor
connections!  Safety console keys can be faked, I value my eyes.  (I
always used a pre-soldered rig with a paper clip loop etc. for even
3-C-engine clusters, less mis-fires that way.  Just 2 connections &
you're set.)

  Mark, mwillis@nwlink.com

Dr. Ed Edmondson, Jr. Ph.D. wrote:
>
> I am really glad to see that all you picsters are so easily amused :-)).
> Technical people with a good sense of humor are hard to find.
>
> <snipped>