Page 55 - 15 Dangerously Mad Projects for the Evil Genius

36 15 Dangerously Mad Projects for the Evil Genius

P A RT S BIN

Part Quantity Description Source
Laser 1 3 mW red laser LED module eBay
IC 1 1 NE556 dual timer IC Farnell: 1094320
R1, R7 2 1k variable resistor (linear potentiometer) Farnell: 1174082

R2, R4, R6, R9 4 1k 0.5W metal film resistor Farnell: 9339779
R3, R5, R8, R10 4 10k 0.5W metal film resistor Farnell: 9339787
R11 1 100 .05W metal film resistor Farnell: 9339760
T1, T2 2 BC548 Farnell: 1467872

C1, C3 2 1μF 16V electrolytic capacitor Farnell: 1236655
C2, C4 2 10nF ceramic capacitor Farnell: 1694335
Servos 2 9 g servo motor 4.5–6V eBay
Battery clip 1 PP3 battery clip Farnell: 1650667

Battery holder 1 Holder for 4 AA batteries Farnell: 1696782
IC socket (optional) 1 14-pin DIL IC socket Farnell: 1101346
S1 1 SPST toggle switch Farnell: 1661841
Box 1 Small plastic project box
Terminals 1 Four-way terminal block Farnell: 1055837

Stripboard 1 Stripboard, 15 tracks each of 20 holes Farnell: 1201473
Cable Four-way ribbon cable, or shielded four-way Farnell: 150431
cable for longer distance control (1 meter)
Base 1 Aerosol can lid Recycling

are happy to wait a week or two for your parts to Figure 4-2 shows the schematic diagram for this
come from China, there are some bargains to be project.
had this way, too. The circuit is based around a dual timer chip,
In addition, you will also need the following one for each of the servo motors. This is described
tools: more fully in the “Theory” section at the end of
this chapter.

T OOLBO X

■ An electric drill and assorted drill bits Assembly
■ Soldering equipment
The following step-by-step instructions walk you
■ Epoxy resin glue or a hot glue gun through making the laser turret. First, we construct
■ A craft knife the joystick, then the laser and servo assembly, and
then the electronics that link it all together.