Making a basic solar powered string of led lights isn't too difficult. This instructable will require no electronics knowledge and no programing.
What were will be doing is upgrading some old battery powered mini lights to LEDs and then using some basic components, charging the batteries with a small solar panel. With the aid on 1 IC and 1 inductor, we can automate the string so it turns off and charges during the day and turns on at night.
Let's get started.
Step 2: What we will need.
I'll tell you what I used, but you can improvise your own parts.
1 Battery powered light set with battery box.
1 Solar Panel 2.0v @ 80mA (I'm using two 1.2v NiMHs in parallel. If you want to use one -then you need 2v @ > 20mA.
1 IC (QX5251F) Will discuss this one later on
1 Inductor 220uF (This is not exact and you can change it to meet your desires.)
10 LED's (White, Blue, Green or Pink) (Red and Yellow are a little different, but you can use them if you really want.)
A soldering iron.
Step 3: Let's make an LED string.
You don't have to make your own string. You can buy battery powered LED string on Ebay for about $2 - $4 depending on the number of LEDs. Then you can just hack the battery box which you'll see in a few steps.
If you have an old Christmas string mini lights, they need to be Battery Operated. If you use AC powered ones, the wiring is not in parallel. You can cut up the AC strings and rewire them in parallel, or you can just get two long wires and solder on the LEDs.
Anyway here is a close up of the prep.