On Dec 8, 9:20*am, Tuno wrote:
The + 12V power lead to my B40 fell out the back of the unit at some
point and made contact with ground during its subsequent tour of the
area behind the panel. The (?)-amp, 5x20mm fuse in the instrument
panel was blown, as well as the 0.25 amp fuse of the same size on the
back of the B40.

I know the purpose of the panel fuse is to protect the wires, and the
B40 fuse is to protect the instrument (I think). Can I safely use a
0.25 amp fuse in the instrument panel and maybe a 0.5 amp fuse in the
B40? (The B40 is the only item on that fuse; the radio, LX and 302
have their own.)

Btw I've checked the B40 manual and can't find any mention of fuses.
Is 0.25 amp the correct fuse?

Thanks

~ted/2NO

Ted,

The fuse is 2 amp. Sometimes if +12v power touches the case of the
B40 a fuse link on the circuit board on the back of the unit is
blown. You can check this by following the circuit and using a
voltmeter.

Richard
www.craggyaero.com