JPS Communications NXU-2, Инструкция по установке и эксплуатации

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NXU-2 Operations Manual
3-10 JPS Communications, Inc.
address of the corresponding server with the SRVRIP command. For example, if a client unit is
going to be connected to a server NXU-2 at address 192.168.1.10, then the command must be
issued:
SRVRIP 192.168.1.10
On the client unit, if you do not want the client unit to connect to a server automatically at
power-up then set the server IP address to 0.0.0.0 by typing SRVRIP 0.0.0.0
3.3.8 COR and VOX Settings
The NXU-2 uses the COR (Carrier Operated Relay) or equivalent signal from your radio to
determine when to send audio data across the network. When the COR input is active, audio is
transferred to the other side of the network. The COR command allows you to select the
polarity of the COR input. If a COR output signal is not available, you may select VOX (Voice
Operated Switching). VOX operation uses the detection of an audio signal from your radio or
other audio device to control the flow of audio from the NXU-2.
Select the polarity of the COR input by using the COR command. COR 0 selects active low
COR, while COR 1 selects active high COR sense. COR 2 selects VOX mode. In VOX mode,
no connection to the NXU-2 COR input is required, since the audio input level itself is used to
determine when a signal is present
. In order to conserve network bandwidth, digital audio
packets are only sent when COR is active. If using the NXU-2 in an application where the
connected equipment does not support the COR line, then the COR line must either be tied to
its active state (in which case audio will be sent across the network continuously) or you must
select VOX mode.
In any case, the COR or VOX mode must be set properly since the NXU-2
uses this setting to determine when to send audio data across the network
3.3.9 VOX Hang Time
When VOX mode is enabled, you may also adjust the VOX hang time. This is the amount of
time the VOX remains active after the input signal falls below the VOX threshold, and may be
set to 500, 1000, 2000, 3000, or 4000 milliseconds. This is useful to prevent the VOX from
dropping out between words or syllables. Use the HANGTM command followed by 500, 1000,
2000, 3000, or 4000 to select the hang time. The factory default is 500 milliseconds.
3.3.10 COR Inhibit Time
In some applications it may be necessary to inhibit the NXU-2’s response to the COR input
(whether hardwired COR or VOX) for a brief period of time (and under certain circumstances)
in order to avoid problems with the “ping pong” effect.
The “ping-pong” effect can occur when the COR output of a device is activated momentarily
by the device when it switches out of the TX mode. There are varieties of reasons why this can
happen (including squelch tails on some radios), and it may occur with COR or VOX, but the
result is the same.
To illustrate the problem, assume that there are two radios connected over a network by a pair
of NXU-2s. An active COR at one end of the network creates an active PTT at the other end.
When the COR of Radio 1 is active, Radio 2 is transmitting, and vice versa. Consider what can
happen when the switch out of the TX mode causes a momentary active COR output: