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erco
08-19-2011, 05:46 PM
Need 5V for a project? Don't have a lot of time? Don't have a lot of money?

The heck with Sizzler! Search "emergency charger" on Ebay to find a variety of cheap DC boosters to generate 5V from one AA battery:

http://www.ebay.com/itm/Blue-Emergency-Battery-Charger-Mobile-Phone-MP3-/270595802314
http://www.ebay.com/itm/Smart-Emergency-Battery-Charger-Nokia-SAMSUNG-phone-/250809928765

or two AA batteries:

http://www.ebay.com/itm/Battery-Emergency-USB-Charger-F-iPhone-4G-3G-3GS-8136-/290557875368
http://www.ebay.com/itm/AA-Battery-Emergency-Charger-iPhone-3G-iPod-Touch-/160589409068

No telling how long they'll last in continuous use, but for $2-3, it might be worth the gamble for light duty use.

HollyMinkowski
08-20-2011, 01:41 AM
Thanks for this link.
That might be useful. I wonder what the
efficiency of the upconversion is? It would be interesting
to see how long I could power a small 5v AVR
project using this and a single 1.5v D size alkaline.

I tried 3 AA cells but the V was not high enough
to run the 1284p at an overclocked speed. 5.5 or
5.7 seems to work OK and this thing says it is
in this range. 4 AA cells delivering 6v is a tiny bit
too much.

I still wonder about the upconversion circuit in those
little single LED flashlights you found on ebay several
months ago. They must put out about 3.5v or so to
drive the white LED from 1.5v. They might be useful
for powering a Prop.

erco
08-20-2011, 02:15 AM
THAT'S the Holly I'm talking about! Stepping up with the BIG IDEAS!

john_s
09-02-2011, 01:28 AM
Idea (little one) - a single push button switch to turn it ON / OFF instead of that old style slide/toggle switch.
Perhaps even to walk through the 3 functions using the same tiny pushbutton... any takers :-)