Hi, I'm new to the group, but my daughter has a Honda now so I'll be
lurking.
I didn't find anything on this exact problem in a search so:

Vehicle is a 1998 Civic DX 5spd.

Dead battery prompted a test of the alternator, which wasn't charging at
all.
Replaced alternator, and externally charged battery overnight. The car
started fine the next morning, and it worked fine for about 1/2 a day,
charging between 13.8v and 14.2v, then the speedo quit working, then that
evening the headlights were dim.

Next morning, battery was weak again, I charged the battery for a while,
then started it, but now there is a no charge condition again, verified with
a Fluke meter at the battery, but not at the alternator.

A brief check of the fuse block under the dash revealed a blown 10A fuse,
Alternator / Speedo. Replaced it, had a charge at the battery, then blew the
fuse when moving the vehicle in the driveway.

I suspect the vehicle speed sensor has a bad connection or is
malfunctioning. Any other ideas before I dive back in tomorrow?

Thanks in advance!

Spdloader