Grig

Just opened my 1541 fuse holder and yup, it's a slo-blo alright. 1A slow-blo. Funny the schematic doesn't mention that. But anyway, wouldn't hurt of course, throwing a fast acting fuse in there. Will either blow more often or not. Added protection if anything.

Common practice back in the day, if you didn't have something like a 1amp slow on hand, would throw a 2amp fast in.

A couple of years ago I had some C= PSU with a broken fuse but only had fast blow at hand. Those were worthless, they blew as soon as I applied power. Then I got some slow bloe ones, and the PSU still works.