Wednesday, October 29, 2014

Mini Breadboards. How to use them

In this post I will try and show how to use a small breadboard.

The first picture here shows a small breadboard, with 170 points for connection. They come in many different colours, this one just happens to be green. The colour makes no difference to the operation.


 
I have added some row numbers and column letters to help clarify things. Most mini breadboards won't have this written on them. They don't need it, they are so small, but for the purpose of making things really clear I think it will help.

On each side of the central gap, the rows are connected together. This is done by a strip of metal formed into a "U" shape under the pin holes. So if I place a wire in (Row 2, column B) and a wire in (Row 2, Column C) they will be connected together.

 There are no "Power rails" on a mini breadboard, so I like to connect + and - into (Row 1). As you can see in the above diagram, this makes all of (Row 1 Columns ABCDE) -ve and all of (Row 2 Columns FGHIJ) +ve
Now we can go ahead and make a circuit! The blue lines represent "Jumper wires"
In this diagram I have connected a jumper wire from +ve to an unused row (Row 1,Column I to  Row 8, Column I) then a resistor bridges the gap by having legs pushed in to (Row 8, Column H and Row 8, Column B).
A second jumper wire connects  the resistor to a new row (Row 8, Column A to Row 5, Column A).
To complete this circuit, an LED is inserted. The longer leg is pushed in to (Row 5, Column B) and the short leg into (Row 1, Column B). If you have cut your LED legs, its easy to see which is the leg that goes to -, there is a flat edge on the rim. The flat edge indicates the - side.



 
To get a second LED to light you can connect them in "parallel". To do this, add your second LED with its legs into (Row 5 and Row 1). You can choose any of the pin holes still available on the left hand side, just remember what we said about the flat edge.

Another way would be to connect them in "series". To do this, remove the second jumper wire we put in. (The one on the left). Replace it with your second LED. Orientation matters! Make sure the - leg of your new LED is in the same row as the + leg of the first LED, and that the + leg of the new LED is in the same row as your resistor.

 Buy Mini Breadboards on our website here
http://www.mallinson-electrical.com/170-point-solderless-mini-breadboard.html


That All Folks! Experiment and have Fun! Please let me know if you are having problems, or would like a fuller explanation on basic electronics.