User Manual

Place one of the disco covers on the disco motor (DM) shaft. Turn on
the slide switch (S1), then push and release the press switch (S2). The
disco motor (DM) spins and its LEDs light, but it is not as fast and the
LEDs are not as bright as in project 10.
With S2 pressed, the disco motor spins faster but the LEDs do not light.
This can help the disco motor to start spinning.
This circuit has the LEDs connected in series
with the motor, while project 10 has the LEDs
connected in parallel with the motor. Connecting
parts in series reduces the power to them, but
makes the batteries last longer.
This circuit is just like the preceding one, but uses the PNP transistor
(Q1) instead of the NPN transistor (Q2). Note that the 5-snap wire is
under the disco motor (DM), partially hidden. Place one of the disco
covers on the disco motor shaft. Turn on the slide switch (S1), then push
the any button on the selector (S8). The disco motor spins and its LEDs
light.
PNP and NPN transistors are
similar, but current flows
through them in the opposite
direction.
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Project 147
Selector with Disco
Ball - PNP
Project 148
Slower & Dimmer Disco
Disco Cover
SUPPORT BAR
Disco Cover
SUPPORT BAR