Elenco Electronics EP-130, Руководство пользователя

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Do you know someone who is a big mouth? (Or,
have you been accused of being one?) This project
lets you and your friends see who’s got the loudest
voice.
You can see how this project works by looking at the
schematic. When you yell into the earphone, your
voice creates electrical energy through the process
of piezoelectricity, the special characteristics of
crystalline substances. The crystal in your kit’s
earphone produces voltage when it is subjected to
mechanical stress – such as the sound pressure of
your voice.
The two-transistor circuit amplifies the electrical
energy from the earphone. You can use the control to
change the amount of the signal from the earphone
that is amplified. The two NAND gates in series
control the lighting of LED 1. Trace 0’s and 1’s as
they change from input to output.
To use this circuit, set the switch position A and set
the control to position 5. Yell into the earphone and
watch LED 1. It probably lights. If so, try turning the
control counter-clockwise to make it more difficult to
light LED 1. (Try adjusting it just a tiny bit each time.)
See how far you can lower the control to reduce the
strength of the amplifier and still light the LED.
Notes:
EXPERIMENT #58: BIG MOUTH
-75-
Wiring Sequence:
o
27-79
o
28-110
o
124-131-31-49
o
33-55
o
41-43-100-81
o
42-72
o
44-109-99-83
o
45-88-78
o
46-80
o
47-115-51-50
o
52-53-54
o
77-71-123
o
119-132
o
40-87-13-EARPHONE
o
121-26-48-116-62-60-59-57-56-84-82-14-EARPHONE
Schematic