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is mounted so that it slides sideways, not up and down. This will prevent G forces from possibly
causing the switch to "bounce", interrupting the power to the Proton, which is not a good thing.
Any slide switch that you use must be rated to at least twice the G forces that you are likely to
see... a $1 Radio Shack special isn't going to cut it, spend a few bucks and get a high-quality
switch.
You can also use a "push-on, push-off" type switch. Many users have had good success with
them, also mounted laterally. You can put the switch just behind one of the air ports, and actuate
it by pushing a small pin/wire through the hole. Just like with slide switches, spend the money to
get a good quality switch.
A better option would be a more positive switch, such as a rotary switch or a screw-type switch
that locks down positively. Since the major forces on rockets are almost entirely along the
longitudinal axis of the rocket, the contacts on a rotary switch are unlikely to be interrupted by G
forces. A popular choice is the Schurter 033.4501 rotary switch, they cost about $5. This is a
special-purpose rotary switch originally designed to be a 120v/220v power supply selector
switch, but it works very well for our purposes. You can get them from a number of online
rocketry suppliers, or you can order one directly from Allied Electronics, a direct distributor for
Schurter products. They're actually about a buck cheaper from Allied, but you'll have to pay
shipping, so chances are pretty good that you're gonna come out ahead if you buy it from one of
the rocketry suppliers because you're probably buying a bunch of stuff from them anyway.
Featherweight Rocketry and Missile Works also make good small screw-type switches, they use
a screw to positively lock down the contacts and completely eliminate any possibility of the
switch being jarred open. You can also make your own screw switch, Google around and you
can probably find some good examples.
Finally, if you want to avoid moving contacts altogether, check out our Eggtimer WiFi Switch
(www.EggtimerRocketry.com). You can turn it on or off using your mobile device too,
independently of your Proton. It may be a bit larger than other switch options but the
convenience of not having to fumble around looking for the switch inside the AV bay more than
makes up for the minor weight and size penalty, and you can safely arm your deployment
electronics from up to 200' away from your rocket. And yes, the WiFi Switch will not interfere
with the WiFi signal from your Proton.
Proton Battery Options
For most installations, we recommend using a 2S 7.4V LiPo battery. You'll need one that's at
least 300 mAH, since the Proton draws 85 mA (it's WiFi... that's the nature of the beast). You
CAN get away with smaller batteries, IF (and ONLY IF) you connect the fully-charged battery
up right before flying. We've used batteries as small as 180 mAH in testing, but we have several
fully-charged batteries on-hand and we change them with a fresh one after each flight. With a
larger battery, you can take your time... a 500 mAH 2S LiPo is about the same size and weight
as a 9V alkaline battery, and will last all day. That's what we use for all but the skinniest of
rockets. For 3" or larger diameter rockets, we like the skinny packs used for Airsoft guns...
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