giant led bar graph
I also have my Screwfix (
But it is available in all power locations, 2 x end heads are provided again from Screwfix
I got mine from Paperchase, but you can use thin cards or plastic from a milk bottle or something.
10x12 v LED unit.
These are designed by big Clive (
And from Phenoptix (
There are 9 x \'super flux led on it.
I used 5 Green, 3 yellow, 2 red to indicate the power level.
3mm Machine screws 20mm
Melt Glue gun or any general glue can work.
Control Circuit: 74 hc595 shift register (
Transistor array (
Capacitor 100uf capacitor strip (
Also known as veroboard)
When I build the mine, the total cost of the parts is about 100 (
Including led £ 60, trunk £ 20, end cap £ 5).
Tools: 3mm hole sawHacksaw for plastic 58mm drill bit drill iron and welding screwdriver-board cutter (
Cut off the track on the strip board
You can do this with a drill.
Mark the distance between light elements.
I used 130mm in the middle of each lighting unit.
I used 150mm at each end with a total length of 1470mm.
Cut the wire slot into length with a hacksaw.
Make sure the end is cut straight.
Drill Guide holes for each light element.
This ensures that they are all in a straight line.
Use a hole saw to cut 10 x holes of the light element.
Stick the end to the \"freeze\" plastic for rolling cut to install the hole.
It needs to be bigger than the hole so you have a surface that you can stick.
You need 10, one for each hole.
Stick them in place and dry them.
Welded LED board.
LED kit available in Phenoptix (
Click on this link).
They contain nine super-flux LEDs (
There are 4 pins in it)
And 4 x resistance.
I am using monochrome, so all LEDs and resistors for each board are the same.
It is very simple to weld them, but it takes a little time and some smoke to weld all 10.
The PCB is designed as an RGB device, but I just use a single color, so all three inputs need to be connected together.
Each LED board has a front lead.
You need to weld the negative control lead on each LED board.
Once you have made the LED board, drill 3mm holes to drill the PCB using the space PCB as the template.
I fixed the plate in place with M3 x 20mm countersunk head screw and lock nut.
For a flat finish, so it can be installed on the wall without scratches, using the counter
The countersunk bit and countersunk machine screws on the back will be better installed in the holes.
I am using a transistor array of 74 hc595 shift registers and ULN2003.
There are 7 outputs (
There are 8 outputs in the shift register, but there are 7 in the transistor array, so I don\'t use one output of the shift register).
The shift register means that we can control more output through several pins of the micro-controller.
It is a serial device, so we send the data to the shift register.
When we set the latch to high level, any sequence we lock in the register will appear in the output.
For using 74 hc595 shift registers in Arduino, see this tutorial.
This has the information you need to control the lights.
You can use a single transistor on each output of the shift register to build it, but that means loading more welding and it\'s a bit of a hassle.
The transistor array type used to control the devices in the neagtive path is ULN2003.
All LED boards have a common positive factor.
This makes the control very easy.
Can handle 500 mA units per device.
About 100 mA whn per LED board, so this should be OK, but checking the current raing is OK for your app.
12v power supply for Led.
The logic works under 5v and is taken out from the micro controller board.
I will use the fuse in case of short circuit.
For some reason, mine.
The Png file looks bad, so I have attached a PDF file of the circuit schematic (28/6/12).
I\'m leaving the street.
Give you board layout.
I will also launch a printed circuit board with this issue (
If you are interested in an email or comment)
But the strip board works fine.
Incoming and outgoing wires: I used a cable with comression fitting grommit.
I also used an output 7 pin socket because the system was designed to have an extra monitor on the output.