HowTo-Color (8) / Hacking Electronics / Simon Monk / 236-3 / Chapter 4
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Hacking Electronics use higher-brightness LEDs or power the project from a lower voltage. If you do decide on this, recalculate the values for R3 and R4 and try it out on the breadboard layout. The 555 timer IC needs a supply voltage between 4.5V and 16V, and the output can supply up to 200mA.
Construction Step 1. Cut the Stripboard to Size There is no point in having a large bit of stripboard with just a few components on it, so the first thing we need to do is cut the stripboard to the right size. In this case, it’s ten strips each of 17 holes. Stripboard doesn’t actually cut very well. You can use a rotary tool, but wear a mask because the dust from the stripboard is nasty and you really do not want it in your lungs. I find the easiest way to cut stripboard is actually to score it with a craft knife and metal ruler on both sides and then break it over the edge of your work surface. Score it across the holes, not between them. When the board is cut, the copper underside will look like Figure 4-23.
Figure 4-23 A stripboard cut to size
Step 2. Make the Breaks in the Tracks A good tip is to use a permanent marker and put a dot in the top left corner. Otherwise, it is very easy to get the board turned around, resulting in breaks and links being put in the wrong place. To make the breaks, count the position in rows and columns of the break from the top of the board layout and then push a bit of wire so you can identify the right hole on the copper side of the stripboard (Figure 4-24a). Using a drill bit, just “twizzle” it between thumb and forefinger to cut through the copper track. It usually only takes a couple of twists (Figure 4-24b and c). When you have cut all four breaks, the bottom side of the breadboard should look like Figure 4-25. Check very carefully that none of the burrs from the copper have lodged between the tracks and that the breaks are complete. Photographing the board and then zooming in is a great way of actually checking the board.
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