Page 172 - 15 Dangerously Mad Projects for the Evil Genius

150 15 Dangerously Mad Projects for the Evil Genius

What You Will Need T OOLBO X

You will need the following components to build ■ An electric drill and assorted drill bits
this project. They are listed in the Parts Bin. ■ Two pencils

When buying the LEDs, look first for very high- ■ Soldering equipment
brightness white LEDs. Those of around 20,000
■ A hot glue gun or self-adhesive pads
mcd will generally have a forward voltage of
around 3.3V, but check this on the description of
the product before you order. If the forward Assembly
voltage is not given in the details, look at another
Figure 12-2 shows the schematic diagram for the
listing—there are usually dozens. Buy a single lot
project. The heart of the project is a 555 timer IC.
(often sold in 50s) since you will be more likely to
This generates pulses that turn on a MOSFET
get near-identical LEDs that way. In any case, buy
transistor that drives the LEDs.
some spares, because I have occasionally found
some duds in these cheap bulk offerings. We first met the 555 timer IC in Chapter 4,
where we used it to generate pulses for our servo
You will also need the following tools for this
laser turret. If you are interested in how this
project that are listed in the Toolbox.
works, look at the “Theory” section at the end of
Chapter 4.

P A RT S BIN
Part Quantity Description Source

R1 1 1M variable resistor Farnell: 1629581
R2, R3 2 10k 0.5-W metal film resistor Farnell: 9339787
C1 1 1μF 16V Farnell: 1236655

C2 1 10nF Farnell: 1694335
T1 1 P-Channel MOSFET FQP27P06 Farnell: 9846530
IC1 1 NE555 timer Farnell: 1467742
D1-36 36 White LED 5mm 20,000 mcd, I 30mA V 3–3.3V eBay
f f
IC socket 1 Eight-pin IC socket (optional) Farnell: 1101345

S1 1 SPST on-off toggle switch Farnell: 1661841
Box 1 Food container with transparent lid Supermarket
Knob 1 Farnell: 1441137

Battery clip 1 PP3 battery clip Farnell: 1650667
Battery 1 9V PP3 battery