Specifications

SB-P-06-4066
sepura
Mobile & Gateway Accessory i/f
specification
30th July 2012
Page 25 of 39
Issue 7c
© Sepura plc 2011
Device state
Key press
Nominal voltage on ACC_KEYS
pin, V
Nominal ADC value
not attached
N/A
5.00
255
attached
None
4.51
230
attached
0
3.94
201
attached
1
3.35
171
attached
2
2.70
139
attached
3
2.00
102
attached
4
1.46
74
attached
5
0.85
44
The accessory keys use a circuit structure like that given below. Resistor values and
associated logical key numbers (which map to functions specified by the Radio Manager) are
as follows:
AUDIO GAIN
Different microphones require different gains settings, e.g., a fist microphone will usually
require a lower gain setting than a remote microphone.
The audio gains of different microphone categories, e.g., fist microphone and headset, can be
adjusted over a 45 dB range via Radio Manager. This gain variation takes place in the
transceiver and is in addition to the console and AIU sensitivity settings, ―normal‖ and ―high‖,
described in section 6.2. The sensitivities for the console and AIU stated in section 6.2 are
achieved when the transceiver audio gain - programmable via Radio Manager - is set to
24 dB.
Accessory
Radio Manager default setting
Covert microphone
30 dB
68R
68
RR
R
82
R
180
R
270
R
560R
5
3
4
2
1
0
ACC_KEYS
GND
Key number =
1800R