FoxhntrPat states:

>Volks- my Diehard battery fluid is above the plates, the terminals look clean
>& well connected.  No battery or other warning lights have come on, but I
>guess they can't be counterd on.  Radio & CB work but turning key produces no
>starting sound whatsoever.  I've been drifting down my hilly driveway to
>jumpstart.  Am I right that my Tugboat ('90 syncro westy) doesn't have a
>catalytic converter this would harm?   I'll plug in the trickle charger
>(snip)

I had a situation very similar to yours, albeit in a Toyota.
Started it up, drove to destination, took care of business,
jumped in, turned the key and...nothing.  Totally dead.
Had the electrical system checked; no problems found.  Battery
appeared to be OK also, but since it was one of those sealed,
no-maintenance deals there wasn't much to do with it.
I ended up getting an Interstate battery and getting some cash
back on the DieHard, and the problem never returned.

I'd check the voltage on your battery first; I think a "normal"
charged battery is somewhere around the 12.4V+ range.  Since
yours is dead and you're trickle charging it, I'd measure after
it's sat around for a little while.
Personally, I'd ditch the DieHard & get an Interstate, but
that's just my opinion, and I'd only do it if I knew there
was nothing wrong with the rest of the electrical charging
system.

Good luck
Norman