That's not true at all, it does not mess with the voltage divider. Reducing the value of R1 reduces the current through R2 and providing the ratio of R1 to R2 remains the same it's fine.But the 5-10mA does vary a little with load, AND it only goes through R2, not R1 so it messes up your voltage divider.
No, you'll need a switching power supply to boost the voltage. Check out www.national.com and use the WEBENCH Designer on their home page. It'll give you a few options that you can do. Or you can try +5v to +12v converter (but I didn't look at it enough to see if it'll work with a 6.5v input though I suspect that it will)Can I use the LM317 to effectively boost voltage from 6.5VDC to 13-14? I have a small home-built solar panel that I'd like to use to charge a 12V battery. If so, what resistor combination would be most effective? I have looked at spec sheets, and am having difficulty deciphering the jargon.
I am new to electronics, and would appreciate any and all help.