P.O. got so excited by all the responses from the TicTac flashlight project that he sent us another of his creations. This time it’s a LED lamp created from the scraps of an old 9v battery and three LED’s. No need to use a resistor here as he’s used three 3.5v LED’s which adds up to a required voltage of 10.5v… which the battery can’t supply. The benefit of this is that you don’t have any losses in a resistor and the battery will end up lasting longer – but the LED’s will not operate on 100%. Take it or leave it, this is a great project that involves few components and has a compact and robust design. |
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May 15th, 2006 at 5:49
cost me £2 to make=0
May 1st, 2007 at 8:18
These 9V batteries are poor performers & costly. IMHO humble AAs, although larger,are far superior & DIRT CHEAP. You can hack a cheap 3 x AA switched battery box & fit a white LED for ~ US$2 all up (including batteries). It’ll still be giving out light nearly 1000 hours later too!
July 21st, 2007 at 15:15
Shure, you can make it every way you want – My intention is to let people think (and you did – THANK YOU). But I have had my 9V battery lamp in 2 years now (as a emergency lamp – not light every day) and the battery is still fresh – I think this is compact, simple solution of a handy lamp.