ADInstruments S7200 Operation Manual page 116

AD INSTRUMENTS
corresponding to the desired transponder. The polarization is selected by
changing the voltage of the LNB supply (13 volts for vertical polarization, 18V for
horizontal polarization). The local oscillator is selected by adding or not a 22kHz
tone on the LNB supply (when 22kHz in on the highest LO is selected). Local
oscillator frequency can be 9750MHz or 10600MHz depending on the location of
the transponder. If the respective transponder is in the lower part of the spectrum
(<11700MHz) the 9750MHz LO is selected, otherwise 10600MHz LO is selected.
The tuner has to be set to the correct frequency using the following formula:
F = F
tuner transponder
With a LNB integrating SaTCR-1 devices, the transponder selection (polarization,
LO selection and frequency translation) is done through a single DiSEqC command
named ODU_ChannelChange.
First stage of a SaTCR LNB (up to the matrix) is similar to a conventional LNB. As a
consequence, the transponder frequency at the input of a SaTCR device is the
same as F with a classical LNB:
tuner
F = F
satcr_input transponder
Then, the SaTCR device should translate the transponder inside the bandwidth of
its associated band pass filter. To perform that operation, the SaTCR VCO has to
be set according to the following formula:
F = F
satcr_voc satcr_input
In addition, SaTCR LNB includes new features that allow auto-detection of its
parameters.
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S7200 TV Signal Analyzer Operation Manual
- F
LO
– F
LO
+ F = I F
bpf transponder
– FL I + F
O bpf