Both the primary (PF Stratologger CF) and secondary (MW RRC2L) altimeters are wired up identically. The electrical bus connections (4-40 standoffs) in the center of the sled are for cable strain relief, allowing the use of thin gauge wire from the altimeters to the bus and tougher lamp cord from the bus to the aft bulkhead (only) for the two sets of DROGUE circuit e-match terminals.
What size airframe did you use this in? 75mm (3") Blue Tube.
Whats the mounting method of the switch? 2x, 4-40 standoffs (inboard side of mag switch) with 2x, 4-40 socket head cap screws securing the Featherweight switch to the standoffs. The switch's mounting screws double as terminals for + in (from LiPo) and +out (to altimeter + in). The single mag switch screw hole closest to the edge of the sled uses no standoff, just a cap screw and nut to hold the two negative cables to the mag switch - circuit.
I'm trying to follow the wiring. Are you switching power or ground to the altimeter? My wiring scheme uses red* for + and black for -. (I only use the apogee DROGUE circuits on the altimeters; MAIN function is handled by a Jolly Logic Chute Release.) By design, the Featherweight mag switch switches + only. The battery's negative cable goes to the switch's - terminal, while a separate - cable runs from this same switch terminal to the altimeter's - in. (In other words, the negative circuit is always hot on both the switch and the altimeters.)
*In my photo, on the mag switch that services the Perfect Flite altimeter, its + OUT cable looks black, but that's just black heat shrink tubing. The wire is actually red. It, and the negative cable from the mag switch too, run underneath the altimeter to the altimeter's + and - power in terminals, respectively.
Best of luck using these well-engineered Featherweight magnetic switches. But you won't really need luck. They are rugged, reliable, and worth every penny for the simplicity and extremely low space claim they lend to building an avionics bay.
