Operating Modes; Mgc Modes - Motorola GX2 EA1000C Series User Manual

Installation and Setup

Operating Modes

Select the preferred GX2-EA1000C*/* operating mode, MGC or AGC.
Reminder—on initial power up, the factory default is Preset/Video mode with a 4 dB
Video mode offset from CW.
The following subsections describe how to set up the GX2-EA1000C*/* based on the
operating mode selected. For more detailed information on operating modes, refer to
Section 4, "Operation."

MGC Modes

To implement MGC mode:
1. Adjust the input signal levels, as previously described in this section.
2. If the BC and NC signals are both applied to the main input, the total CW input signal
power should be approximately −14 dBm total power or +34.75dBmV. This is the
sum of the main and narrowcast input signals (NC -6dB below BC).
3. Confirm that appropriate RF input signal connections to the G- to F-type interface
connectors on the rear of the GX2-HSG* are complete.
4. Measure the RF levels at RF TP
panel.
5. Select Preset mode and allocate time for the AGC to adjust the RF signal levels to
the laser diode to the optimum operating point.
6. The RF drive level is optimized during manufacturing to achieve the link performance
required for each laser. The factory-default, laser-drive level, is the operating point in
Preset mode.
7. Select Manual Equate mode. This sub-mode equates the Preset Mode RF-drive-level
(to the laser diode) to Manual mode and enables you to perform any additional level
adjustments from a known good operating point.
8. Manual Equate is a momentary sub-mode and, after the microprocessor configures
the RF parameters, the GX2-EA1000C*/* is automatically switched to Manual mode.
9. If it is necessary to optimize for C/N or distortion, use the RF attenuator to adjust the
RF drive level to the laser diode.
Increasing the drive levels more than 0.5 dB above the Preset mode optimum drive level
may result in the appearance of clipping artifacts in analog video signals.
GX2 EA1000C*/* Multi-Wavelength DWDM 1550 nm Laser Transmitter • User Guide
589569-001-a
(RF input level) on the GX2-EA1000C*/* front
1
B
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