Itu-R Multiplex Power Controller; Multiplex Power Threshold - Orban OPTIMOD-FM 5500 Operation Manual

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OPTIMOD-FM DIGITAL OPERATION
B1/B2 Xover (Band 1 to Band 2 Crossover Frequency) sets the crossover frequency
between bands 1 and 2 to either 100 Hz or 200 Hz. It significantly affects the bass
texture, and the best way to understand the differences between the two crossover
frequencies is to listen.

ITU-R Multiplex Power Controller

The ITU-R recommends that the power in the composite baseband signal (including
the pilot tone), integrated over any 60-second interval, not exceed the power in a
sinewave that modulates the FM carrier to 19 kHz (25.3% modulation re ±75 kHz
deviation). Many European countries are now enforcing this recommendation. (See
ITU-R 412 Compliance on page 3-10 for more information.)

Multiplex Power Threshold

Your Optimod provides a means to limit the integrated multiplex power to the ITU
standard by a closed-loop technique that allows you to use any preset and to create
customized presets freely. The multiplex power controller is adjusted via the ITU412-
9 control (see step 20 on page 2-21). Set it OFF if your country does not enforce the
Figure 3-1: Multiplex Power over 15 Minute Observation Interval
with MPX Power Controller Active, measured at Optimod's Composite Output