Nautel XR12, Руководство по предварительной установке

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XR12 Transmitter Pre-installation Manual Other considerations
Page 7-2 Issue 0.17 2005-08-31
Installing an external RF drive source
1. If the RF drive for one or both exciters is to be applied from an external source, connect its
wiring as follows:
• Route RF drive coaxial cable through a cable entry hole in the cabinet and through the
ferrite toroid, to the vicinity of the remote interface board.
• Cut the RF drive coaxial cable to length, terminate it with a coaxial BNC connector and
connect it to the remote interface board’s EXT RF connector (J6).
External 10 MHz frequency reference
You can apply an externally generated 10 MHz signal (such as a GPS clock signal) for use as the
reference frequency for the RF drive (carrier frequency) to the synthesizer board.
1. The external 10 MHz frequency reference must:
• remain stable at 10 MHz within ± 20 Hz
• have a peak-to-peak amplitude of between 2.2 V and 8.0 V (sine wave or square wave)
• be spectrally pure, since spurs may pass through to the transmitter output.
2. Configure the synthesizer by setting E2 to 1-2 and E1 to 1-2.