Simple automatic solar light is great electronic hobby project which is quite different and simple. As we know, that every electronic hobby contains a unique method to be followed. It has also a principle which should be followed for making this project. This method works efficiently in providing higher brightness during the night.
In the project, we will make automatic solar LED light for small solar charger. Well, this hobby needs to have one LED light which gives brightness in higher. But during the day it will charge the battery as well. This is the method which provides great backup for lighting the LED.
We will use 2AA hybrid battery with voltage 2.4 v at 500 MA. There should be current 50 MA- 80 MA. Avoid white LED. A Relay can be used in this circuit, but it requires high current 80 MA, Whereas are solar cell has only 10 MA hence we use transistor rather than relay.
During the day, the Solar will supply voltage to diode D1 to transistor Q1. So it does not have bias current to base of Q2 when it is off, LED goes out.
At that time, The solar current will be charging the batteries. When there will not be sunshine it will not work that time.
Conclusion about automatic solar light-
After following whole the principle we will be able to get light from LED. But keeping in mind, all jobs must be done carefully.