4-20
Section 4: Operation
Moseley SL9003Q
602-12016-01 Revision J
Function Settings
Summary
FWD
1.00 Watt (nominal)
Output Power of TX
REV
0.07 Watt (nominal)
Reverse (or reflected) power at antenna port
PA CUR
1.8 Amp (nominal)
Power amplifier current consumption
TEMP
29.0 deg C (nominal)
Power amplifier temperature
SYNTH
LOCK (nominal)
UNLOCK
Indicates phase lock of the 1
st
LO
AFC
2.4 VDC (nominal)
1
st
LO PLL AFC Voltage
LO
100% (nominal)
1
st
LO relative power level
XCTR
100% (nominal)
Transmit module’s relative output power level
Warning on Adjusting Transmit Power
Attempting to increase the transmit power will cause the radio to fail
to operate.
The digital QAM modulation used in the SL9003Q is very spectrally efficient and
extremely
sensitive
to channel linearity. When shipped from the factory the system is operating at its
maximum transmit efficiency.
The transmitter power amplifier consumes the most current so is operated close to its peak
output power, 10 Watts (+40 dBm) for highest efficiency. This provides an averaged output
power, 1.25 Watts (+31 dBm) and acceptable intermodulation distortion (IMD) for the
receiver to effectively equalize. Increasing the transmit power beyond this factory set level
will generate increased IMD, and result in data errors at the receiver. The higher order QAM
modes are particularly sensitive to IMD.
This IMD issue is also raised with the addition of post-amplification or booster amplifier. This
amplifier must be a linear Class-A amplifier. Class-C power amplifiers used with analog FM
STLs will not work. The post-amplifier compression point should be between 6 dB (16 QAM)
and 9 dB (64 QAM) higher than the expected average transmit power.
Summary of Contents for Starlink SL9003Q
Page 86: ...5 22 Section 5 Module Configuration Moseley SL9003Q 602 12016 01 Revision J ...
Page 90: ...6 4 Section 6 Customer Service Moseley SL9003Q 602 12016 01 Revision J ...
Page 110: ...A 10 Appendix A Path Evaluation Information Moseley SL9003Q 602 12016 01 Revision J ...
Page 118: ...D 2 Appendix D Microvolt dBm Watt Conversion 50 ohms Moseley SL9003Q 602 12016 01 Revision J ...