Bruce: Interesting FD trivia. I have some observations based on your
reporting of the relevant rules.
The field-day rules about not charging batteries -- even from solar
cells -- while in use do seem a bit foolish. But the foolish rules can
be sidestepped with a bit of foolish circuitry:
|\ |
solar _______| \|____________________________________ radio
cells | | /| | equipment
| |/ | |
| |
| |
| |\ | |\ | |
|___| \|___ battery battery ___| \|___|
| /| being in | /|
|/ | charged use |/ |
This may require periodic swapping of the in-use and being-charged
batteries. This can be done either manually, or with relays, or with
solid-state switches. The first case will require shutting down the
equipment for a minute or two. The last two cases avoid this, provided
that a (big enough) capacitor is put across the load. But, to toe the
line with the rules, the switches better be break-before-make.
In fact, it looks like solid-state battery switching could be used even
if the batteries are being charged from a generator, or, for that
matter, from commercial mains. I wonder if the ethics of this parallel
those of using a "spider"?
Bottom line: compromise. Solid-state switching of batteries being
charged from commercial mains appears to comply with the letter --
though clearly not the spirit -- of the rules. So, don't do it. In
return, lean heavily on the spirit when interpreting the prohibition
against charging in-use batteries. That is, assume it wasn't meant to
be appled against charging from solar cells. --John/K2MM
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