Specifications

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WARNING: Disconnect primary power prior to servicing.
precisely at the ideal locations. However various imperfections in the signal path
cause the actual constellation points to deviate from the ideal locations by finite
error vectors. The modulation error ratio quantifies the ratio of the desired signal to
the undesired error vectors. MER is typically associated with COFDM modulation
formats such as DVB or DAB.
MCM (Master Control Module):
A circuit card in the transmitter control unit (TCU) in dual drive systems. The MCM
card provides most of the core control functions, whereas the TCU card controls the
user remote & GUI interface.
PA (Power amplifier):
An electronic circuit that accepts a low level RF signal and outputs an amplified
replica.
PAB (Power amplifier block):
A high power amplifier stage. May refer to the LPU power block (PAB zero in
lower-half amplifier section of LPU chassis) or one or more external high power
amplification stages (PAB 1…4).
PCB (Printed Circuit Board):
A circuit board in the transmitter.
PCM (Processor Control Module):
A circuit card in the transmitter control unit (TCU) in dual drive systems. The MCM
card provides most of the core control functions, whereas the TCU card controls the
user remote & GUI interface.
PFRU (Precise Frequency Reference Unit):
A circuit sub-assembly inside the LPU modulator section responsible for supplying
the various high-stability oscillator signals required to synthesize the transmitted RF
waveform.
PRBS (Pseudo-random binary sequence):
An endless series of random numbers typically used for transmitter test purposes,
often when a valid transport stream does not exist.