Manual

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Project 142 Burglar Alarm Box
Assembly
(adult supervision recommended):
1. Place battery holder (B3) and base grid
supports on base grid A.
2. Place parts on grid E, and install into
base grid support on grid A. The pegs
should be facing inward.
3. Place parts on base grids B & D, except
for the 2 vertical snap wires (V1) that
attach to grid E and the parts connected
to them.
4. Install grids B & D into base grid supports
on grid A, attaching the vertical snap
wires (and the parts connected to them)
on grid E as you do it. The pegs should
be facing inward.
5. Install grid C into base grid supports on
grid A, attaching the 2 vertical snap wires
as you do it.
6. Add the 4 stabilizers to help secure grids
B-E together.
7. Place the remaining parts on grids A & C.
8. Place the Q4 attachment on the
phototransistor (Q4).
Turn on the slide switch (S1); the white LED
(D6) is on, but there is no sound. An alarm
sounds if you reach in and block the light
between the white LED and phototransistor.
You can place something
in this box, and have an
alarm sound if someone
tries to take it.