Before igniting a spirited discussion on the subject of wiring a panel, I'll cheerfully disclose that I have no formal training and have a hard time trying to explain how an electron moves from one place to another. This said, how do we resolve an apparent conflict. The technical wizards at Garmin say in no uncertain terms that with shielded cables (comm primarily) the shield must be grounded at both ends. Other technical wizards at L3/Goodrich Avionics(WX500 Stormscope) are adamant that shielded cables (Tx/Rx) must only be grounded at one end. In the case of the Wx500 talking the the MX20, the Tx cable is to the shielded at the processor end only and the Rx cable shielded at the MX20 end only. Never mind the fact that the WX500 install manual calls out for these cables to be shielded at both ends.

I suspect there may be a ground loop potential in here somewhere and would welcome feedback from anyone one on the list who actually makes a living do'in this stuff day to day.

I've got the WX500 up and running on the bench and haven't blown the thing up yet so maybe there's hope. ):

Angier Ames
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