Elenco Electronics EP-130, Руководство пользователя

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Anything look familiar about the schematic for this
project? This circuit uses an R-S flip-flop circuit
made from NAND gates, similar to the circuit in
Project 44 (“TTL R-S Flip-Flop”).
After you finish building this project, set the switch to
position A and press the key. You should hear a
sound through the earphone. Try pressing the key
several times. This should not affect the sound in
your earphone. Now move the switch to position B
and press the key one more time. What happens
now?
Circuits like this can be used in alarms. They are
very useful since intruders often can’t figure out how
to make the sound stop. You might also want to
experiment using light from LEDs instead of sound
to tell you that the circuit has been set or reset.
Notes:
EXPERIMENT #55: SET/RESET BUZZER 1
Wiring Sequence:
o
13-77-75-49-45
o
14-119
o
40-109-85
o
41-106-79
o
42-55-51
o
43-105-81
o
50-78-131
o
52-53
o
54-76-133
o
132-138
o
44-110-71-EARPHONE
o
121-137-62-60-59-57-56-80-82-86-72-EARPHONE
o
13-14 (POWER)
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Schematic