Optus to launch 3rd D series satellite

Stuart Corner
Friday, 30 March 2007 09:56

Business IT - Networking

Was Optus D1 satellite a crippled bird?
In November 2006, Crikey reported that the $US140 million D1 satellite was "suffering from what the company describes as a 'configuration problem'" that "could affect the services to New Zealand's 650,000 pay TV homes..[and] may also cause flow-on issues with a range of Australian clients including the behind the scenes operations of Australian television networks including the ABC, Nine Network, Network Seven and SBS."

The report said: "Satellite enthusiasts are speculating that Optus D1's main New Zealand transponders may have been designed on the wrong polarity – meaning that they are effectively pointing the wrong way to be received in many New Zealand homes. Optus could neither confirm nor deny this."

A satellite industry insider told iTWire at the time: "My intelligence from the insurers indicates that the problem is indeed related to polarisation and there is likely to be a partial loss claim."

Another source told iTWire: "What appears to have happened is that the New Zealand spot beam on the new D1 satellite has been configured to the wrong polarity and apparently even if all LNBs [low noise block downconverters] throughout NZ were re-aligned (a major task for Sky) the signal would be 6dBW down on the original spec."

An LNB is basically a very efficient amplifier which converts the satellite frequencies (11-12 GHz in Ku-band) down to a lower frequency which can more efficiently be transmitted on a coaxial cable into the home. It is a small box that sits at the focal point of the dish. A 6dB reduction represents a 75 percent reduction in power, so would be quite serious. However another source said that the changes neede to the LND would not require a truck roll.

A contemporary Television NZ news report on the issue  can be found here.