In article <3uonft$gnm@news.sas.ab.ca>, ghalinda@freenet.edmonton.ab.ca
says...
>I'm going to build the flash power pack described in the December 1994
>issue of Camera and Darkroom, to use with my Nikon SB-24 and Vivitar 283
>flashes. The article recommends starting with 2 1/2 amp slow-blow fuse,
>and going up in 1/2 amp increments if it blows. The power pack holds 4 D
>cells in series, giving 6 volts output. Does anyone have any advice on
>which fuse to use, and if the trial and error method is safe for my
>expensive flashes? Any other tips on this homemade power pack, or on
>better alternatives? What about using C cells to save size and weight?
>I'm also looking for ideas for a carrying case that won't look gaudy
>when I use the pack to shoot a wedding.

The SB24 works so well with nicads that I stopped using external packs,
and I no longer have to deal with the heavy packs and awkward cords.
(Recycle time is about 3 seconds max, though usually the ready light
doesn't even go out - and a set of nicads lasts many rolls.)
Radio Shack now sells an excellent 850 ma/hr AA nicad, though regular
500 ma/hr AA's have worked well for me. Learn how to properly charge
and discharge nicads. [I have never had any of my 20 or so cells go
bad]). If you wish to make the pack described above, the method of
sizing the fuse seems o.k. I would not bother with C cells. Put the
pack out of sight in the camera bag, or in a small belt case.
Alternative packs: 5 "D" 4 amp/hr. nicads in a pack (large, and
awkward to keep batteries in sets); or a 4 amp/hour sealed 6-volt
lead-acid battery (heavy, no "memory", compact, cheap [about $15]
and self-contained). (Handle carefully if near full discharge,
which should be avoided, if possible.) I would recommend using
fast-blow fuses with the "D" nicads and lead-acid batteries to
protect YOU in case of a short. You may need a much larger fuse
size, like 6-8 amps with fast fuses to avoid losing the fuse
during the high start-up current when the flash begins to recycle.
And I would recommend putting 2 1 ohm, 10 watt resistors (Radio
Shack, again) in parallel, and the pair in series with the fuse to
save the flash from the high currents available from the low internal
resistence of the big nicads and the lead-acid batteries.
Hope this helps.