[R-390] R-390A fuse installation

[Miles B. Anderson]

The easiest place to put a B-plus fuse on an single-fuse R-390A is at the
cathode of the rectifiers (tube or solid state) underneath the power supply
subchassis. In fact, if you clean up the ends of the fuse cartridge with
steel wool and are reasonably quick with the soldering iron you can just
pigtail the wiring onto the fuse itself without bothering with a fuse post.
Just be sure to cover the whole thing with an insulating sleeve -- my choice
cambric "spaghetti" tubing but shrink tubing will work fine. That way, you
don't have to open the wiring harness or bore a hole in the back panel. The
second B-plus fuse, which is on the drop side of the filter capacitors is
really unnecessary.

Miles Anderson, K2CBY
16 Round Pond Ln
Sag Harbor, NY 11963