Elenco Electronics EP-130, Руководство пользователя

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White noise is a noise that has a wide frequency
range. The shower-like noise you hear when you
tune your FM radio to an area with no station is one
kind of white noise. It is a useless noise normally,
but when you play electronic musical instruments,
you can use white noise as a sound source.
When you finish building this circuit, set the switch
to position A to turn on the power. Look at the
schematic. We will use the noise that is generated
when you apply a reverse voltage to the base and
the emitter of transistor Q1.
IC 1 acts as an oscillator. The output of this oscillator
is rectified (remember this term from Project 99
(“Sound Alarm Circuit”) by diodes D1 and D2 and
flows to Q1. IC 2 amplifies the noise so that you can
hear it through the earphone.
Notes:
EXPERIMENT #107: WHITE NOISE GENERATOR
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Wiring Sequence:
o
64-90-13-EARPHONE
o
121-114-112-46-47-70-96-84-85-14-EARPHONE
o
93-48-101
o
94-111-127
o
82-88-63-132-126
o
76-89-65
o
113-66-81-83
o
77-91-67-110
o
68-95-92
o
69-80-87-86
o
78-79
o
109-128-125
o
119-124
o
122-131
o
102-75
Schematic