Elenco Electronics EP-130, Руководство пользователя

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Here’s a circuit that imitates more of our feathered
friends - you could say it mocks the mockingbird!
Complete the circuit as shown below and slide the
switch to position A to turn on the power. You won’t
hear any sound from the speaker yet. Press the key
and you’ll hear a chirping sound from the speaker.
Release the key - you’ll still hear the chirping sound,
but then it will slow down and stop. You can see that
when the key is released, the first transistor “Q1” is
cut off from the battery. The second transistor “Q2”
can still produce the chirping sound, until transistor
“Q1” stops controlling it through its base.
Try a different value capacitor in place of the 10
μ
F
and the 100
μ
F capacitors and hear what happens.
These capacitors control the amount of electricity
reaching the transistors through connections to the
transistor bases. Remember to keep notes on your
experimentation.
Notes:
EXPERIMENT #2: THE CHIRPING BIRD
Wiring Sequence:
o
1-29
o
2-30
o
3-106-110
o
4-41-131-138
o
5-44-109
o
40-114-91-75
o
42-85
o
43-105-86-77
o
119-45-115-113-92
o
76-137
o
78-116
o
120-132
Schematic