Digital Voice Systems VC-20-ATC-10B, Руководство пользователя

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Section 2 - VC-20 AMBE™ Vocoder Board Overview
VC-20

ATC-10b Vocoder Board User’s Manual
page 4
The Speech Compression Specialists
D
IGITAL
V
OICE
S
YSTEMS,
I
NC.
The VAD signal should be held low to enable the onboard Voice/Silence detection and
Adaptive Comfort Noise features. When enabled the ENSLNCE signal is switched to
indicate the presence of Voice. If the VAD signal is held high or left disconnected, both
Voice/Silence detection and Adaptive Comfort Noise are disabled, and the ENSLNCE
signal always indicates voice.
Note that for proper operation any background noise present in the speech must be short
term stationary and have a level less than -25 dBm0.
2.3 Special Handling and Storage Precautions
CAUTION
Handling Instructions
Although the VC-20 AMBE™ Vocoder Board incorporates input protection circuitry,
to avoid damage from the accumulation of a static charge, industry standard
electrostatic discharge precautions and procedures must be employed during handling
and installing.
Storage
To insure maximum shelf life in long term storage, VC-20 AMBE™ Vocoder Board
should be kept in a moisture controlled package at <40
°
C and <90% RH.