I need some help from the more erudite amongst us on the subject of putting
diodes across inductive devices.

I understand that these devices are operating coils of relays like the
starter relay, master relay and any other relays that are used in various
operating circuits of the a/c.  I have relays for the flap jack and heavier
circuits that I do not wish to switch direct like pitot heat, dual landing
lights, main supply to hydraulic pump as wll as relays to control the supply
to the essential bus and power distribution bus.  I have basically followed
Jim Frantz's diagram in the Dec/Jan 1998 of LNN.

I also believe that a diode is needed on the key switch/starter/mags, but
again I do not know where or why.

I have three questions:

1.    What do the diodes do for me when installed?
2.    What will happen if I do not use diodes?
3.    How do I install them (which way do                         they face)
and what size/spec diode do I                 need?

Any help will be most welcome.  As you can see I am down to the final
details.  This year maybe!!!!

Ian Crowe
C-FKRO