Slight whine in radio

You need to fuse at both ends for proper protection. Both battery and component end need to be fused on both Pos and Negative leads on all electrical equipment.

 

Yes, what kd5rdx says.
I actually put a 50-amp fuse in the "big red" lead at the battery, to protect the wire against dead shorts along its run. Then I put a proper sized fuse for the radio close to the radio.
I just use a proper sized fuse in the "big black" lead at the battery, since a dead short to ground of the ground lead won't let out any smoke, but a fault in the system's ground that tries to use the radio as its ground path is already a problem. I don't want a small external load to keep going through the radio's ground lead, and a 50-amp fuse might not blow.
So, a caveat in my earlier suggestion that only produces 4 connections in each power lead actually skipped one of my steps (and two more connections, at the smaller fuse).
Hope I didn't confuse things for anyone.
-- Handlebar --