Elenco Circuit Maker Sound Plus 200 - Manual (Page 36)

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Project #64
NPN Light Control
Project #65
NPN Dark Control
Turn on the slide switch (S1),
the brightness of the LED (D1)
depends on how much light
shines on the photoresistor
(RP). The resistance drops as
more light shines, allowing
more current to the NPN (Q2).
Turn on the slide switch (S1),
the brightness of the LED (D1)
depends on how LITTLE light
shines on the photoresistor
(RP). The resistance drops as
more light shines, diverting
current away from the NPN
(Q2).
Project #66
PNP Light Control
Project #67
PNP Dark Control
Turn on the slide switch (S1),
the brightness of the LED (D1)
depends on how much light
shines on the photoresistor
(RP).
The resistance drops as more
light shines, allowing more
current through the PNP (Q1).
This is similar to the NPN (Q2)
circuit above.
Turn on the slide switch (S1),
the brightness of the LED (D1)
depends on how LITTLE light
shines on the photoresistor
(RP). The resistance drops as
more light shines, so more
current gets to the 100kW
resistor (R5) from the
photoresistor path and less
from the PNP-diode path. This
is similar to the NPN circuit
above.
CM-200_Manual_031914.qxp_CM-200_Manual_031914 4/2/14 12:04 PM Page 36