Nautel NX400, Руководство по установке

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NX400 Installation Manual Commissioning tasks
Page 10-6 Issue 1.0 2017-06-30
Modulation checks
Verify that the RF output is appropriately modulated when audio is applied:
1. Connect an appropriate modulation monitor to the control/interface PWB’s
RF MONITOR
BNC
connector (J7). The RF monitor level is factory set for 5 Vrms. Ensure there is
sufficient attenuation installed between the
RF MONITOR
connector and the modulation
monitor.
2. From the AUI’s Presets menu, select the desired preset and verify the
AM Source
is set for
your audio signal generator.
3. Verify that an audio signal generator is connected to J11 (AES1) or J12 (balanced analog) on
the control/interface PWB, and that its output is preset to 1,000 Hz at a zero output level
(turned off).
4. Turn on the audio signal generator and increase the output level of the audio signal generator
until a modulation depth of 100% is attained, as indicated on the modulation monitor. The
audio signal generator's output level should be at the user-defined input level (e.g., 10 dBm)
set in the preset.
5. Use the modulation monitor to verify that the RF output's modulation envelope is acceptable.
6. Set the output level of the audio signal generator to zero (off).
7. Turn off the RF power stage: press
RF Off
. The
RF Off
button will turn red and the
Rf On
button will turn grey.
8. Disconnect the audio signal generator from J11 or J12 on the control/interface PWB.