Setting up a new breadboard
Before you use your new breadboard there are a couple of things you should first understand about how it works, and then possibly perform a couple of initial activities.
Breadboards come in various sizes and are usually specified by the number of holes or tie-points they have. The 840 tie-point board is a pretty standard version and you should try and start with a board around that size. You will be amazed at how quickly you start to run out of space but even on this modest size board, you can construct some quite complex circuits.
The breadboard holes will accommodate most wire ended components or components with pins if they are at the common 0.1" (2.54mm) lead spacing. Where you may struggle is with some of the components with either odd lead spacing or with thicker leads. The humble 1N4007 diode for example is a very tight fit on some boards. It is possible to use surface mount components but you will need a carrier board to mount them on first.
More details here on carrier boards and in the rest of the breadboards section of this site.
Breadboards come in various sizes and are usually specified by the number of holes or tie-points they have. The 840 tie-point board is a pretty standard version and you should try and start with a board around that size. You will be amazed at how quickly you start to run out of space but even on this modest size board, you can construct some quite complex circuits.
The breadboard holes will accommodate most wire ended components or components with pins if they are at the common 0.1" (2.54mm) lead spacing. Where you may struggle is with some of the components with either odd lead spacing or with thicker leads. The humble 1N4007 diode for example is a very tight fit on some boards. It is possible to use surface mount components but you will need a carrier board to mount them on first.
More details here on carrier boards and in the rest of the breadboards section of this site.
Each board usually has two power distribution strips; one top and the other at the bottom and the tie points on these strips are connected horizontally.
The centre of the board consists of columns; 64 on the 840 board with each column having 5 tie points, an insulated break and then another 5 tie points.
The image on the left shows how the tie points for the power distribution strips (red and black), and then columns (yellow). There is NO connection between the 5 points in the top columns and the 5 points in the lower columns.
The boards are usually made from three modules (the two distribution strips and the main board itself) that are locked together and it's possible to separate the boards into their separate parts if required. The individual parts have interlocking lugs and sockets on them allowing you to lock together multiple boards in pretty much any combination you wish. However, boards from different manufacturers often will not interlock correctly.
To separate the boards modules, hold the middle of the board with one hand, grab the distribution strip with the other and gently break or "snap" the two apart. There is usually a sticky foam pad underneath that will crease as you start to bend the sections apart. Run a sharp knife blade along the crease and the sections should then come apart easily.
Notice how the distribution strips in the image on the left have the negative at the top, and the positive at the bottom. There is no standard and they can be either way around. They also often use blue for negative.
Another "feature" that manufacturers like to include for your "convenience" is that the distribution strips sometimes have a break in the centre.
The picture above is of one of my breadboards. You will see that there is a break in the two red and blue lines indicating that the left and right sides of the rail are not connected. I've got some boards where the red and blue lines are continuous BUT there is still a break.
When you purchase a board CHECK and don't assume the pretty painted coloured lines are correct.
Usually it's a good idea to insert a couple of wires to link the two red and two black rails together. You can always pull these wires out of you need to use separate voltages for the two strips; sometimes when using operational amplifiers that require +ve, 0v and -ve for example.
The picture shows the power cable that connects to my PSU plugging into the top right. Because of the two bus interconnection wires shown, power is available on both top and bottom buses and this will make your projects neater and simpler to construct.
On the underside of the board there is usually a thin piece of double-sided sticky foam. There is a plastic backing that you can peel off and allows you to stick the board down and is useful if you want to create a large bread boarding area from several boards interconnected.
Be warned, if you do stick the boards down they are really difficult to unstick.
When you purchase a board CHECK and don't assume the pretty painted coloured lines are correct.
Usually it's a good idea to insert a couple of wires to link the two red and two black rails together. You can always pull these wires out of you need to use separate voltages for the two strips; sometimes when using operational amplifiers that require +ve, 0v and -ve for example.
The picture shows the power cable that connects to my PSU plugging into the top right. Because of the two bus interconnection wires shown, power is available on both top and bottom buses and this will make your projects neater and simpler to construct.
On the underside of the board there is usually a thin piece of double-sided sticky foam. There is a plastic backing that you can peel off and allows you to stick the board down and is useful if you want to create a large bread boarding area from several boards interconnected.
Be warned, if you do stick the boards down they are really difficult to unstick.
What's on the inside
The above image is of the middle section of a board that I've had for many years. It's actually no longer in regular use as it's basically worn out. Notice how over time it's started to curl up at the ends. It "was" stuck down to a piece of wood and formed part of a large breadboard but for some reason the plastic started to warp.
I flipped the board over and used acetone to remove the rubber backing revealing the metal contact strips.
If you look at where the contact strip has been removed, you will see that it sits inside a channel or grove. This provides excellent electrical insulation between adjacent contact strips and so it's impossible for the lead of a component to accidently make contact with another contact strip.
Looking at the inset image of the contact strip you will notice that the ends are slightly flared and this is to help guide the wire or component lead into the contact correctly. However, it's possible for the lead or wire to catch the top of the contact and if you push too hard you can bend the contact out of shape. If this happens you will get all sorts of odd results in your projects. If when inserting a wire you don't feel it "grab" you should be wary of that contact as it may be making a bad electrical connection.
It is possible to replace or even sometimes repair contact strips but it's a fiddly and messy job especially if the backing foam is particularly stubborn.
If you look at where the contact strip has been removed, you will see that it sits inside a channel or grove. This provides excellent electrical insulation between adjacent contact strips and so it's impossible for the lead of a component to accidently make contact with another contact strip.
Looking at the inset image of the contact strip you will notice that the ends are slightly flared and this is to help guide the wire or component lead into the contact correctly. However, it's possible for the lead or wire to catch the top of the contact and if you push too hard you can bend the contact out of shape. If this happens you will get all sorts of odd results in your projects. If when inserting a wire you don't feel it "grab" you should be wary of that contact as it may be making a bad electrical connection.
It is possible to replace or even sometimes repair contact strips but it's a fiddly and messy job especially if the backing foam is particularly stubborn.
Neat or birds nest
There are two basic ways of wiring projects on a breadboard.
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Method 1 - The neat way.
Notice how the wires lay on the board and are all nicely routed and bent at 90 degree angles. Yes it's very pretty and nice to look at but it takes an age to do. You have to individually cut each wire to exactly the right length. Breadboards are there to allow for rapid prototyping and experimentation and this method is more suited for an art project in my opinion. However, if you do like this approach there is an interesting Kickstarter project from some kids that have designed a really simple tool to help. https://www.kickstarter.com/projects/1094241997/ohmkara-breadboarding-multitool-electronics-protot Method 2 - The birds nest. This, believe it or not, is my preferred way of wiring a project. It's fast to do and you can concentrate on what you are trying to accomplish rather than trimming wires to 1mm length precision but it requires care. A long pair of pointy tweezers will make your life a lot simpler when the board starts getting busy like in the image on the left or if you have large hands and find it tricky getting your fingers into tight spaces. You grab the wire or component lead close to it's end with the tweezers, guide it over the right point and just push it in. In no time at all you will become very proficient at this. |
Interconnection wire
Use insulated 1/0.6mm (1 solid strand with a diameter of 0.6mm) copper wire. It has good current carrying capacity, is easy to work with and obtain and fairly cheap. It's also available in a good selection of colours. Do NOT be tempted to build even a simple circuit using wire of all the same colour as I promise you will end up letting the magic blue smoke out of your components very quickly.
I found the below image of somebodies project on the Internet.
I found the below image of somebodies project on the Internet.
You can see from the image that there are several power distribution bars with two on the left and then one top, middle and bottom. This is quite a common configuration, but now look at the wire colours used.
In the top left red circle the designer has linked both rails of the vertical bus on left, to the top horizontal bus using two white wires.
In the middle red circle a white and blue wire has been used, and in the bottom left circle a green and blue.
From this it's impossible to tell which is positive and which is negative.
Now look at the black IC in the middle of the centre red circle. The top left pin is +5v and the bottom right (hidden under a dark green wire) is 0v. Both these pins are connected to a bus rail using a short orange wire.
Looking at the colours, it would appear that orange, white, light green and dark blue are used for both positive and negative.
This is lazy, carless and a recipe for disaster.
Typically you should use red for +ve and black for 0v. If you have multiple voltages in your circuit then you need to decide which colours carry which voltages and STICK TO IT.
Don't be tempted to grab the first piece of wire that you see on your bench that's the right length.
Remember that when you've finished with your project you can reuse the wires you've cut so over time you will end up with quite a nice selection of different lengths and colours.
In the top left red circle the designer has linked both rails of the vertical bus on left, to the top horizontal bus using two white wires.
In the middle red circle a white and blue wire has been used, and in the bottom left circle a green and blue.
From this it's impossible to tell which is positive and which is negative.
Now look at the black IC in the middle of the centre red circle. The top left pin is +5v and the bottom right (hidden under a dark green wire) is 0v. Both these pins are connected to a bus rail using a short orange wire.
Looking at the colours, it would appear that orange, white, light green and dark blue are used for both positive and negative.
This is lazy, carless and a recipe for disaster.
Typically you should use red for +ve and black for 0v. If you have multiple voltages in your circuit then you need to decide which colours carry which voltages and STICK TO IT.
Don't be tempted to grab the first piece of wire that you see on your bench that's the right length.
Remember that when you've finished with your project you can reuse the wires you've cut so over time you will end up with quite a nice selection of different lengths and colours.
They aren't for every project
To finish off, I have to say that breadboards aren't suitable for every project.
Circuits that run at high frequencies or high voltages or currents are not suitable for bread boarding. Besides issues with stray capacitance between contact strips you can get cross-talk between all those touching wires. There are ways around some of those limitations and in general, you should be able to breadboard almost all of your creations without too much issue.
Circuits that run at high frequencies or high voltages or currents are not suitable for bread boarding. Besides issues with stray capacitance between contact strips you can get cross-talk between all those touching wires. There are ways around some of those limitations and in general, you should be able to breadboard almost all of your creations without too much issue.