User Manual

Table Of Contents
RF-Orchestra!™ Transmitter Installation and Operation Operation
July 2000 6880493G02-C 5-31
Alarm Reporting
The RF-O! transmitter constantly monitors the various components of the transmitter for
conditions that may degrade or interrupt normal messaging traffic. When such a condition is
detected, the appropriate error code is added to the error log (RFO FIPS: a 104). In cases,
where the transmitter must cutback or shutdown, an alarm is added to the alarm log (RFO
FIPS: a 99
).
Subchannel Configuration Control
The RF-O! transmitter can transmit on up to three FLEX or ReFLEX (FM) subchannels or two
InFLEXion (AM) subchannels, simultaneously. The subchannel configuration control portion
of power control assures that the power output is adjusted correctly based on the number of
subchannels and type of modulation.
Power Amplifier Configuration Control
The number of operational power amplifiers is constantly monitored by the RF-O! transmitter.
If a PA failure is detected by the RF-O! transmitter software, the transmitter takes the
appropriate action. In a two-PA system, if one PA were to fail, the RF-O! transmitter would
continue to operate at a reduced power output level.
Carrier Feedthrough Nulling
The carrier feedthrough (CFT) nulling feature of power control is responsible for removing the
carrier feedthrough component of the spectrum from the center channel. If the CFT
component is not minimized, messaging quality can suffer in the form of audio distortion
(InFLEXion), or garbled messages (FLEX/ReFLEX). The carrier feedthrough component of a
transmission is shown in Figure 5-17.