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Ok so I am new to this and I am working on a project that I really need some help on, it is probably simple for some however I have struggled for a while, so here it goes: I want to wire a valve which is currently powered by two (2) AAA batteries, to a 12volt larger capacity battery and a solar panel to keep the battery charged. I have researched this quit extensivly and what I ahve found is that I need to use some 10k ohm resistors so make the output 3 volts but I have yet to wire it correctly. Any help on this would be greatly appreciated and since I have found this site I can practice wiring it together so I quit wasting parts.

@dyoung180,

Welcome to CL.

More research needed.

Google:

solar battery charger circuit schematic

http://www.circuitstoday.com/car-battery-charger

http://electroschematics.com/6888/solar-battery-charger-circuit/

http://electroschematics.com/4746/solar-charger-circuit/

http://www.rrp.infim.ro/2007_59_1/art07Azooz.pdf

Then you need to regulate the 12V down to the 3V of the original two AAA batteries.

It is unwise to use a simple dropper resistor if the load current varies widely.

You can regulate both solar panel to 12V car battery and 12V to 3V using linear or switched mode converters. Switched mode converters are usually more efficient.

Why not use two or maybe three NiMH rechargable batteries (two will give you only 2.4V , three will give you 3.6V) instead of a 12V lead acid?

Ok thank you for the links and the info I will definitely try this way and let you know.

you could try a "LM350" variable voltage regulator it will handle 5 amperes which will cover any small motors or coils you may be driving resistor networks put off heat which can be problematic not to mention waste