Agc Modes - Motorola GX2 EA1000C Series User Manual

Installation and Setup

AGC Modes

To implement AGC modes:
1. Adjust the input signal levels per the GX2-EA1000C*/* specification, as described
previously in "Measuring and Checking the RF Input Signal Levels."
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 or +34.75 dBmV. This is the sum of the
main and narrowcast input signals (NC -6dB below BC).
3. Make the appropriate RF input signal connections to the G- to F-type interface
connectors on the rear of the GX2-HSG*.
4. Measure the RF levels at RF TP on the GX2-EA1000C*/* front panel.
5. Choose which AGC mode you prefer to use—Preset or Set.
6. If you choose Preset mode, allocate time for the AGC to adjust the signal levels to
the laser diode to the optimum operating point. Additional level adjustments are not
required.
7. If you choose Set mode to optimize C/N or distortion, then select Set Equate. This
sub-mode equates the Preset Mode RF-drive-level (to the laser diode) to Set mode
and enables you to perform any additional level adjustments from a known good
operating point.
8. Set equate is a momentary sub-mode and, after the microprocessor configures the
RF parameters, the GX2-EA1000C*/* is automatically switched to Set mode.
9. If necessary, adjust the OMI offset from the Preset level to optimize for C/N or
distortion.
10. If you want to proof the system using CW carriers, set the Video/CW mode to CW.
11. For normal video operation, select the appropriate video mode offset (2, 3, 4, or 5
dB) from CW.
GX2 EA1000C*/* Multi-Wavelength DWDM 1550 nm Laser Transmitter • User Guide
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