Manual

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9. Proximity Sensor
Build the circuit, move the magnet (7) towards the
red switch (83) and the bi-directional LED (71) will
turn on blue.
Move the magnet (7) away and the light will turn
off. Install the bi-directional LED (71) in the reverse
direction, then move the magnet (7) towards the
reed switch (83) and the bi-directional LED (71)
will turn on red. Proximity sensing like this is often
used to control lights in a room that come on when
people enter and go off when the last person exits.
10. Fire Drill Alarm
Build the circuit to the left making sure the alarm
(78) is in the correct direction. Press the switch
(62) and you will hear the alarm (78). This type
of circuit could be used for re drill tests where a
switch is turned ON to set off the re alarm for the
re drill and then turned OFF when the re drill is
over.
Red Light
Blue Light