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does buck work on its own
yes
no rails are shorted (probed in advance)
reasonable power supply current
does hot plugging with battery kill it
doesnt die
how does it look onscope?
looks good, see photos
Does it power rpi
yes
(pin order is correct on the header and variant is satisfactory)
Software Testing
does killswitch kill uart when harness breaks?
does pixhawk uart comms work when killswitch disabled via shorting header pins
does pixhawk uart comms work with killswitch disabled via pixhawk gpio?
do power leds work
do uart indicator leds workdoes killswitch work
Flight Testings
does it work on a flight test?