BAT SIMULATOR

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BAT SIMULATOR

• J. L. Errington

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BAT SIMULATOR

• To mimic a bat sound we need to have a signal
  with a frequency of 45 KHz or 90 KHz repeating at
  a frequency of 8 Hz.
• The bat simulator used two NE555 timers. The
  component used for the practical circuit is a
  dual NE 555 called an NE 556.
• The first stage runs at 8Hz and controls the
  second stage that operates at 45kHz or 90 kHz
• The sound is produced by a piezo transmitter

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Circuit diagram for bat simulator
9V
9V
1
14
2.2mF
1nF
2
NE556
13
3
12
4
11
39K
Piezo sounder
5
10
16K
16K
6
9
7
8
45 or 90KHz
8 Hz
F 1.44 / 2 R C Here R 16 K or 8K, C 1nF
Hence F 45KHz or 90KHz
F 1.44 / 2 R C Here R 39K, C 2.2mF Hence F
8Hz