Solar Cell Working - Principle of Solar

The circuit illustrated below is used as Solar Cell. You can get plate from your old faulty solar calculator. Carefully dissemble plate with out tearing its 2 wire. Connect both wire to a LED through a switch. When Solar Plate is kept in sunlight and switched ON you will see LED glows .
Please make sure for the correct polarity of LED. Theory :
When energy is added to pure silicon, for example in the form of heat, it can cause a few electrons to break free of their bonds and leave their atoms. A hole is left behind in each case. These electrons then wander randomly around the crystalline lattice looking for another hole to fall into. These electrons are called free carriers, and can carry electrical current
Solar Plate can be made by :
Step 1
Stain the Titanium Dioxide with the Natural Dye
Step 2
Coat the Counter Electrode
Step 3
Add the Electrolyte and Assemble the Finished Solar Cell

 

How Solar System Works ? Learn by Animation

Source : circuiteasy.com/

A Simple Walkie-Talkie Circuit Diagram

Click on the image to Enlarge 

Simple - Build the transmitter.

http://www.zen22142.zen.co.uk/Circuits/rf/2bjttx.htm

Then the reciever.

http://www.electronics-tutorials.com...o-receiver.htm

Tune them both to the same frequency and use a switch to change between transmit and recieve mode.

White-LED Voice Transmitter and Receiver

Click on the image to Enlarge

Components for the transmitter

Normal 1W white LED

Condenser microphone

74HC4046 PLL IC

CA3130 BiMOS Op Amp IC

100 kohm

5 kohm

50 nF

1 kohm

2 Mohm

100 pF (x2)

5.6 kohm (x2)

Components for the receiver

Centronic OSD100-E (Eye-response photodiode)

74HC4046 PLL IC

CA3130 BiMOS Op Amp IC

33 kohm

0.1 uF

240 kohm

5.6 kohm (x2)

100 pF (x2)

10 uF

1 nF

100 kohm (x2)

250 kohm trimpot

Mono audio socket (to speakers)

Two 9V batteries.


Waveforms Taken at White LED Output

Fig. 1. Waveform without voice input.

Fig. 2. Waveform with voice input.

Waveform at the Receiver

Fig. 3. Waveform at receiver output (i.e. at the audio socket).

Circuit Schematics

 

Pictures of the Project

 

 

Video Demonstration

Source : extremecomputation.blogspot.in