JPS Communications NXU-2, Инструкция по установке и эксплуатации

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NXU-2 Operations Manual
3-14 JPS Communications, Inc.
3.5.2 Audio Input Test Point
Access to an audio test point, TP1, is provided via the rear panel so the actual audio signal
voltage applied to the A/D converter can be measured with an AC voltmeter. The correct level
for best operation as measured at TP1 is about 0.2V or –12dBm (600 ohm reference.)
3.5.3 Audio Output
The audio output from the NXU-2 is a low impedance (10 ohm) unbalanced AC coupled
output. The output level is adjusted by the OUT LVL potentiometer accessible from the rear
panel. This output provides a 0 dBm nominal level; +15 dBm clipping into a 600 ohm load.
The audio output will supply signal levels from –30 to +11 dBm.
3.5.4 COR Input
The COR input to the NXU-2 is a high impedance input and can be programmed to be active
high or active low. In the active low configuration the input is pulled up to +5V DC internally
through a 47K ohm resistor. In the active high configuration, the input is pulled down to ground
through a 22K ohm resistor. The logic threshold is 2.5V DC nominal, and the input is protected
from momentary surges up to +100 V DC.
3.5.5 AUX Inputs
The AUX inputs (AUX IN0 and AUX IN1) are high impedance inputs, and are always active
low. They are pulled up to +5V DC internally through a 47K ohm resistor. The logic threshold
is 2.5V DC nominal, and the input is protected from momentary surges up to +100 V DC.
3.5.6 PTT Output
The PTT output from the NXU-2 is an open drain type. It can sink up to 100 mA of current,
and can withstand open-circuit voltages up to +60V DC. In order to avoid conflicts with
internal pull-up resistors on the PTT lines of some radio equipment, there is no internal pull-up
resistor on the NXU-2 PTT output.
3.5.7 AUX Outputs
The AUX outputs from the NXU-2 (AUX OUT0 and AUX OUT1) are open drain types. They
can sink up to 100 mA of current, and can withstand open-circuit voltages up to +60V DC.
These lines are pulled up to +5V DC through a 47K ohm resistor.