Elenco Electronics 202 - Manual (Page 61)

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Project #119
NPN Collector
OBJECTIVE: To compare
transistor circuits.
Project #120
NPN Emitter
Compare this circuit to that in
project #117, it is the NPN
transistor (Q2) version and
works the same way. Which
circuit makes the lamp (L2)
brighter? (They are about the
same because both transistors
are made from the same
materials).
OBJECTIVE: To compare
transistor circuits.
Compare this circuit to that in
project #118. It is the NPN
transistor (Q2) version and
works the same way. The same
principles apply here as in
projects #117-#119, so you
should expect it to be less bright
than #119 but as bright as #118.
Project #121
NPN Collector - Motor
OBJECTIVE: To compare
transistor circuits.
Project #122
NPN Emitter - Motor
This is the same circuit as in project
#119, except that it has the motor
(M1) instead of the lamp (L2).
Place the motor with the positive
(+) side touching the NPN
transistor (Q2) and put the fan on it.
The fan will not move on most
settings of the resistor (R1),
because the resistance is too high
to overcome friction in the motor. If
the fan does not move at any
resistor setting, then replace your
batteries.
OBJECTIVE: To compare
transistor circuits.
This is the same circuit as in
project #120, except that it has
the motor (M1) instead of the
lamp (L2). Place the motor with
the positive (+) side to the right
and put the fan on it. Compare
the fan speed to that in project
#121. Just as the lamp was
dimmer in the emitter
configuration, the motor is not
as fast now.
!
WARNING: Moving parts.
Do not touch the fan or motor
during operation.
!
WARNING: Moving parts.
Do not touch the fan or motor
during operation.