Microwave Radio Communications SCM4000, Technical Reference Manual

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Troubleshooting 4-14 SCM4000 Operator’s Guide/Tech Ref Manual
No Data/Corrupted
Data Incorrect modulation mode - Due to the
way that the unique word is used to
indicate a carrier lock, the Demodulator
may indicate a carrier lock when the
Modulator is using a different modulation
scheme. • Verify the modulation modes on both the
transmit and receive sides match.
• Contact technical staff.
If problem persists,
possible hardware failure.
Contact MRC Technical
Support .
PRBS turned on in the Modulator - In
order to test the quality of the link, the
PRBS generator may be turned on in the
Modulator and the Demodulator. During
this time, no valid data can be passed. • Verify that the PRBS generator is turned
off on the transmit and receive sides.
• Contact technical staff.
Input signal turned off on the Modulator -
The Modulator has a menu to turn an
interface on or off. If this is off on the
Modulator, data will not be passed. • Turn the interface back on in the
Modulator.
• Contact technical staff.
Inverted spectrum - The Modulator
provides the capability to invert its output
spectrum to account for differences in RF
hardware (low-side vs. high-side up-
converters and down-converters). This
must be set correctly for the RF path
being used. • Turn spectral inversion on or off on the
Modulator, as necessary. When in doubt,
it should probably be off.
• Contact technical staff.
Table 4-8: General System Problems (Continued)
Problem Possible Cause Suggested Operator Action
Suggested Technical
Staff Action