[Amps] inexpensive HV fuse

[Herzog]

back in the 50's  I had saved my favorite piece of RG8 coax.
I saved a foot of it just to use for fuses.  Who knew what wires other 
vendors used.
One strand of it's shield would blow about equivalent to a 4 or 5 amp 
fuse. My meters were crude, and how long did you want to wait to see if 
you had a thermal fuse, or a fast blow.

I just drilled a hole in each of the blown fuse, (
that I didn't want to go to the store again, as of course the new fuse 
blew too.).  and threaded the wire thru, using my mom's needles.  I 
soldered the end to the metal cap.
This worked fine, even though I never cleaned out the old blown fuse 
inside.  probably works just as well for higher than the 250 volt 1 inch 
standard glass tubes.  Test the blow point of your wire yourself with 
the wire open air and a variable low voltage supply.  The voltage of 
whatever your are replacing should be a big enough gap.

It is big challenge to get anything small enough to protect a tube's 
grids; and even a bigger one for those semiconductors!!!
===============

RE: Response time, guys!!!
Any thermally operated fuse is TOO SLOW to protect the tube.
Besides, the spring can carry many tens of Amperes before it heats up enough
to melt.
You'll probably blow up diodes and tube and God only knows what else!
Alex	4Z5KS