Appendix C.- Frequency Offset Adjustment For Tuning Analogue And Digital Channels - Promax 25 User Manual

USER'S MANUAL. PROMAX-25
APPENDIX C.- FREQUENCY
ANALOGUE AND DIGITAL CHANNELS.
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 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.
Figure 27.- Frequency offset on the tuning central frequency.
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.
09/2004
OFFSET ADJUSTMENT FOR TUNING
Page 35