the SWITCHED battery terminal, effectively completing the igniter circuit with the high-
resistance continuity-check circuit of the WiFi Switch. The WiFi Switch uses optoisolators to
isolate the higher-voltage from its circuitry, and there’s a 10K resistor in series so it typically
draws under 1 mA of current… you don’t need to worry about it firing your igniter, but it’s
plenty enough current to tell the optoisolators to turn on.
To make life easier, we’ve tried the WiFi Switch with a number of popular altimeters, and
we’ve posted connection diagrams on the Eggtimer Rocketry web site. If your altimeter isn’t
listed, drop an email to us at
, chances are good that we can
tell you how to hook it up.
