Data Sheet
-42-
60. Tornado Drill
Build the circuit as shown on the left and you will light up the
two LEDs at the same time. If you turn on the switch (62),
the two LEDs will be turned off and the alarm (78) will sound.
This circuit could simulate a tornado drill in your school where they
intentionally turn off the lights while activating a tornado alarm and
have you practice where to go and what to do during a tornado.
61. Help!
Replace the switch (62) with the press switch (61). The two LEDs
will still be on at the same time. If you press the press switch (61),
the two LEDs will be turned off and the alarm (78) will sound.
Try using this circuit as a Morse code generator and tap in the code
below. This stands for S.O.S, or Save Our Souls. If you ever hear
this sound, then it means someone is in danger and calling for help.
62. Angular Light Intensity
Replace the switch (62) with the reed switch (83) and you will
light up the two LEDs at the same time. If you touch the reed
switch (83) with the magnet (7), the two LEDs will be turned
off and the alarm (78) will sound.
While it may appear that the bi-directional LED (71) is brighter
than the heart LED (69), this is because most LEDs have
angular light intensity proles such that a majority of the light
emits straight out of the top of the LED. If you look from the
side at the bi-directional LED (71) you will see it looks very
dim, just like looking at the side of the heart LED (69).
2nd level
2nd level
S O S
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