On Tue, 7 Feb 2006 15:56:18 -0600, "john graesser"
wrote:


wrote in message
roups.com...
Need to charge some SLAs and other lead acid batteries for field day Im
trying to make
something work without buying a new battery charger, so here goes.
I need to charge a alot of different voltage lead acid batterys
6,8,10,12, ect. I have a
old charger that only puts out 12-14vdc, I have a 10amp 120vac
powerstat (variac) im thinking
of adding to the input of the transformer to reduce output . Will this
work?
Im not sure about the inductance & operating a transformer @ 1/2 or
2/3 the normal 120 vac
input voltage, im wandering if this will effect efficiency or if it
will work at all.

To get battery credit, didn't the batteries need to be charged by something
other than power line current? I thought they had to be solar, wind, water
etc charged so that you couldn't just plug in a battery charger into a wall
and charge them the easy way.
Not to put a damper on your using batteries for field day, but you might
want to check the rules. Here we use a big diesel generator for the radios,
but some wanted their logging laptops plugged into the wall instead of the
generator and a spirited argument broke out whether that negated the credit
for not using lines power.

If he's using batteries and not recharging them with a motor generator
or the power line, then he's running battery power and gets a
multiplier of 5. Where they were previously charged isn't an issue.

He can still charge them:

6.9. Batteries may be charged while in use. Except for Class D
stations, the batteries must be charged from a power source other than
commercial power mains. To claim the power multiplier of five, the
batteries must be charged from something other than a motor driven
generator or commercial mains.

But doesn't get the multiplier.

The spirit of the thing is that the contest is a test of emergency
preparedness. If he had the foresight to have a bank of batteries
charged when the power failed, then he is "prepared."

Considering that it's a bit warm at the end of June in Tucson and half
the mountains in the state were on fire (wait till this year, 110 days
without rain and counting), I stayed home and ran 1E. I could actually
(and did) run for quite a while on just battery power but I
periodically ran the Honda generator to charge it.

Still didn't do to badly. One man, one band and only 17 hrs on the air
and still third highest number of QSOs in my category in the nation.