ITC 220 Base Station, Locomotive & Wayside Radio Transceiver Field Service Guide PN 0046300120 Rev. A
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Figure 27 Typical transmission spectrum EVM (Half-DQPSK)
5.9.2.1
ADJUST RF POWER OUTPUT
Base station transceivers are rated for 75 W PEP, Locomotive transceivers are rated for 50 W PEP, and Wayside
transceivers are rated for 25 W PEP. To achieve rated power, transceivers are calibrated at the factory. If additional
tuning is required, use the
TXPOWER
command to increase or decrease output power relative to the current power
level.
Notes:
You cannot adjust power above the factory-calibrated setting.
π/4DQPSK is a linear modulation technique.
To adjust RF output power for a Base Station or Locomotive Transceiver
Base Station and Locomotive Transceivers can operate at full-rate π/4DQPSK modulation and a maximum duty cycle of
50% for Base Station and 30% for Locomotive Transceivers. (Wayside Transceivers operate only at half-rate π/4DQPSK
modulation and the maximum transmit duty cycle for Wayside Transceivers must be held to less than 10%.)
1.
Key up the transmitter for full-rate π/4DQPSK modulation using the following commands in XtermW:
STOP
SCHED,DEL,ALL
DSP_MODE,IDLE
DSP_MODE,TEST
L1_TEST,SET,TXFREQ,value