User's Manual

ST-3118D SM R 1.1 SMARTRUNK SYSTEMS, INC.
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6.1.2. ANALOG External Mic Gain:
It aligns external microphone
Accessory Port) sensitivity. Default
factory value is 0.0dB.
Figure 29: External Microphone Sensitivity Alignment
Alignment step is 3.2dB.
For noisy environments or when
voice encryption is used, we
recommend keeping it as low as
possible.
Press [OK] to store it in the file.
The value will be updated after the
file is transferred to the radio.
6.1.3. Analog AGC
ST-3118 has an Automated Gain
Control for analog microphone.
This function adjusts the gain to
reach a dynamic gain value, which
makes the analog voice deviation be
equivalent to the right deviation
produced by 50mV RMS on the
microphone output, and the
selected target gain.
If you want to use AGC, then you
must select the target equivalent
gain on the Mic Gain then check the
ACG Check Box.
For example, if you want a dynamic
gain which causes the same effect
that a gain of 6.4dB when the voice
on the microphone causes 50mV
RMS in the microphone switch
output (standard voice at 4 inches
away from the microphone), or 0dB
gain on the external microphone
connection, then you must program
the Analog Gain at 6.4dB and check
AGC as bellow:
Figure 30: Analog Microphone AGC Control
Press [OK] to store it in the file.
The value will be updated after the
file is transferred to the radio.
6.1.4. DIGITAL AGC
ST-3118 has an Automated Gain
Control for digital microphone path.
This function adjusts the gain to
reach a dynamic gain value, which
makes the voice to be equivalent to
the right voice digitally played back
in the other end, produced by 50mV
RMS on the microphone output,
and the selected target gain.
If you want to use AGC, then you
must select the target equivalent