Duo LNB

A Duo LNB is a double low-noise block downconverter (LNB) developed by SES for the simultaneous reception of satellite television signals from both the Astra 23.5°E and Astra 19.2°E satellite positions.

It is a monoblock LNB, which comprises two feedhorns with a single body of electronics containing the LNB stages along with switching circuitry to select which received signal is passed to the output(s). The Duo LNB uses linear polarisation.

A Duo LNB can be purchased in most parts of Europe but it is particularly marketed to Germany, the Netherlands, Belgium and the Czech and Slovak Republics.

Duo LNBs operate as universal LNBs and are manufactured under various brand names, such as Maximum and Inverto, in single, twin-output and quad-output versions – with one, two and four outputs (independently selectable for polarisation and frequency band), respectively, for one, two or four receivers/tuners.

The Duo LNB is available in two versions - the original Duo LNB for dishes of 80 cm or 85 cm diameter and the Duo LNB II for dishes of 60 cm.

The Astra 23.5°E orbital position was established as a major source of direct-to-home (DTH) broadcasts for central and western Europe with the launch of Astra 3A at the end of 2007, and some channels moved there from other satellite positions (in particular 19.2° east) so viewers, who were unable to erect two dishes to receive transmissions from both positions, had to choose between them.

In particular, the Czech CS Link and Slovak SkyLink networks moved to Astra 23.5°E, and the Dutch Canal Digitaal launched a new thematic bouquet at 23.5° east in October 2007. The Dutch regional broadcasters all moved to Astra 23.5°E in September 2007, to be lost to viewers without access to the new satellite position.

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Wikipedia