A Solar Powered Reading Light

Using the basic Solar charger developed here, we can build a very simple and effective reading light. Bright enough to light a small room, it is more than bright enough to work by, and a day's recharging is all it needs to provide over 2 hours of use. 

A garden-variety solar cell (2-volt, 20mA) is all that's needed, and the entire circuit consists of ten basic components.

Step 1 The Parts List

The  components required are:

BC327 PNP transistor
BC337 NPN transistor
1N914 or 1N4148 Low power signal diode
10K resistor
5.6-ohm resistor
100uF 6v capacitor
330pF capacitor
100uH inductor (A larger can-type is chosen for its lower internal resistance. Thanks to acmefixer for bringing this up!)

1 x Red LED 20mA
1 x White LED 100mA. A wide angle unit (90-degrees or more) is recommended here to avoid glare and hot-spots. I also chose the piranha style so I can get the 90-degree angle when I assembled it.

Connecting and Mounting hardware.

Comments

[acmefixer]

QS, what I'm really interested in (and see no info on) is what is the battery holder and where did you get it from??

[qs]

It's made from a cut down 'AA' holder. The details were previously posted under 'My Blinkie Thingie' here.