Appendix E Unicable Primer - emitor Satlook Micro G2 Manuel D'utilisation

Appendix E UniCable Primer

UniCable or SCIF (Single Cable Interface) is a method of translating Satellite frequencies
from the LNB to the user. It is intended to allow multiple receivers to share the same
coaxial cable.
With a standard Universal LNB, with Horizontal and Vertical polarity and low and high
band, there are four frequency ranges that can be selected from the LNB by using the
13V/18V and the 22kHz signal. In order to allow multiple receivers to operate using a
single coax cable, UniCable operation requires the receiver to send the desired
frequency using a DiSEqC command. A UniCable LNB or Switch may be used. For a
UniCable Switch, the LNB input is usually a Quattro LNB which provides the four
frequency ranges to the switch. For a UniCable LNB, the Switch and the Quattro LNB are
integral.
To tune a frequency on the UniCable LNB (or Switch), the receiver issues a DiSEqC
command which indicates the Satellite Frequency needed, the Polarisation, the Band and
what User Band to use. The number of User bands differs but normal is 4 or 8.
The User Bands which are available can be determined by sending a DiSEqC command to
emit RF tones at the centre frequencies of the User bands. By scanning the frequencies,
the User Bands are located. To find out what number User Band this is, another DiSEqC
command is sent to turn off the tone at User Band XX. By selectively turning the RF tones
off, the number of the User Band is determined. Alternatively, The User Band Frequency
allocation is usually provided on the LNB/Switch description. The placement of the User
bands within the spectrum is not the same between manufacturers.
For further detail on UniCable, see the specification EN 50494 – Satellite signal
distribution over a single coaxial cable in single dwelling installations.
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