bolt thrower wrote:
: I am completely ignorant when it comes to solar power.

Check out http://www.homepower.com

: I have a 9vdc 200mA wall-wart for my scanner.

: I want to run the scanner off of solar power when I can.

: I assume a 12v solar panel will not work, and a 75w panel will be
: overkill...

You're comparing apples and oranges. 12v is 12 volts and 75w is 75 watts
.... many 12v panels are 75 watts. There are plenty with fewer watts and
some with more. By the same token 75 watt panels come in 12v and 24v
versions (maybe others, I don't know)

Besides, like wall-warts, a power supply only needs to be rated at an
equal or higher value (in watts or amps or mili-amps) than the device
needing power. The device will only use as much power as it needs. So
you can run a scanner off a 9v power supply that can handle 300 watts
... if you could find one.

: I also assume that a handful (6 to be exact) of 1.5v solar cells
: wired together will give me 9v with plenty of mA's to run the scanner.

Like regular batteries voltage and mA's are seperate values. If you have a
1.5v solar cell it will handle a certain amount of current .. for the sake
of argument say .. 50 mA. Putting 6 of them in series give you 6 volts at
50 mA. Putting them in paralel give you 1.5 volts at 300 mA. It all
depends of the value of the cells you find. I doubt you'll find individual
cells powerful enough so that you only need 6.

As someone else suggested .. I think your best bet would be to get a 12
volt battery and charge *that* from a 12v solar cell. Get an adaptor from
Radio Shack to convert 12v (it'll have a cigarette lighter plug on the
end) to 9v. Or if you're handy with electronics get a voltage regulator
chip and wire it up properly.

That way you can run your scanner with "solar power" any time of the day
or night!

Richard in Boston, MA, USA