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Command
MODEM 19200
MODEM 9600
MODEM 9600M
MODEM 4800
MDS 05-4670A01, Rev. E
is selected followed by
MODEM 9600M
conforms to the channel constraints for a 12.5 kHz ETSI-compliant
channel. Table 15 defines the relationship between digital modem selec-
tion and analog operation.
Table 15. Relationship Between Digital Modem Selection
followed by...
followed by...
followed by...
followed by...
Modem transmission/reception characteristics are further qualified by
the
(emphasis) command. When
EMP
applied on the transmitter and de-emphasis is applied on the receiver.
This setting is typically used in operation with voice radios. To disable
emphasis, select
EMP OFF
Audio signal levels are governed by the
mands. Both commands support a range from -20 dBm to 0 dBm. For
RX operation, this means that a received signal at the peak deviation will
be scaled to the specified
transmit input signal of the specified
specified peak deviation for transmit. Note that
to
to automatically scale the input to the target deviation. Values
AUTO
outside the expected range will cause clipping of the RF signal.
By default, built-in squelch thresholds automatically mute the receive
audio when a signal is not present. To bypass the squelch controls, enter
the command
SQUELCH BYPASSED
the command
SQUELCH AUTO
8.5 Upgrading the Radio's Firmware
From time to time, GE MDS releases new firmware for its radio prod-
ucts to take advantage of engineering improvements or to add opera-
tional features. New firmware can be installed into existing radios in the
field, bringing them up to date with the firmware shipped with new
units.
Firmware files are available free of charge online at:
www.gemds.com/app/support/downloads
NOTE: Only firmware specifically designed for this model of radio
can be installed in the unit.
SD Series Reference Manual (x710 Mode)
MODEM NONE
and Analog Operation
Agency
Command
Compliance
MODEM NONE
FCC/IC
MODEM NONE
FCC/IC
MODEM NONE
ETSI
MODEM NONE
ETSI
is entered, pre-emphasis is
EMP ON
.
RXLEVEL
. For TX operation, this means that a
RXLEVEL
TXLEVEL
. To restore normal operation, enter
.
, analog operation
Analog
Peak
Chan. Size
Deviation
25.0KHz
5.0 kHz
12.5KHz
2.5 kHz
12.5KHz
2.0 kHz
12.5KHz
2.0 kHz
and
com-
TXLEVEL
will translate into the
can also be set
TXLEVEL
48
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