And Digital Channels - Promax 27 User Manual

USER'S MANUAL. PROMAX-27
APPENDIX C.- FREQUENCY
It is possible to introduce an offset of the tuning central frequency for the channels
defined in each channel plan using the ∆FCH parameter (± 2.5 MHz). Therefore, it is
possible to adapt the measures to irregular tunings, due to small displacements on
channel central frequencies that are defined by the standard channel plan.
Taking as example the previous figure, if we suppose that in the configuration
parameters of the digital channel (CH-33) a frequency offset equals to 1 MHz has been
defined for the channel tuning frequency (∆FCH = -1MHz), although the central
frequency corresponding to channel 30 (569 MHz) does not match with the defined one
for the current CCIR channel plan (CH-33, 570 MHz), it will be possible to take
measures corresponding to the Docsis normative for the standard FCC channel plan
(CH-30, 569 MHz) with no need to modify the current channel plan or to enter a new
one.
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07/2008
OFFSET
ANALOGUE AND DIGITAL CHANNELS.
Figure 37.- Frequency offset on the tuning central frequency.
ADJUSTMENT FOR TUNING
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