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More TV satellites to cover Australia Advances in satellite technology & an increasing availability of launch vehicles looks set to bring a smorgasbord of programs to those willing to equip themselves for satellite reception during the late 1990s. By GARRY CRATT Until now, electronics enthusiasts have had few “birds” from which to draw those elusive and fortuitous satellite sign­ als. For those suitably equipp­ ed, the sources have to date been limited. The list comprises Australia’s own Optus B1 and A3 satellites, the ageing Pacific cluster of Intelsat satellites, and the higher powered Russian “Gorizont” series of domestic spacecraft. 6  Silicon Chip Designed to be utilised by wellequipped commercial tele­ v ision networks, the signals emanating from such satellites are often weak, requiring specialised narrow bandwidth receiving techniques and often complex dish tracking mechanisms to have any degree of success. For those enthusiasts patient enough to toler­ate these drawbacks, the results can often be rewarding, provid­ing an uncensored look at the world through this high technology medium. But thanks to a new breed of higher powered spacecraft, satellite reception will soon become much easier. The latest generation of spacecraft, soon to be launched to fill the growing Asian “transponder gap”, operate at much higher power levels, reducing the necessity for large aperture dishes and eliminating the need for dish tracking. Apart from television distribution, these satellites will play a vital role in the distribution of data and telephony in regions previously isolated by geographic location. This great advantage of satellite communications has been seized upon by some countries seeking to register as many orbital “slots” as possible with the world regulating body, the ITU, for consequent “sale” or “lease”. Slot profiteering The main target of accusations about orbital slot prof­iteering is the tiny kingdom of Tonga which, through a corp­ ora­ tion named Tongasat in 1989, applied for and was granted 31 orbital slots. After due debate, this was finally reduced to six. Rights to use all six orbital locations have now been granted to two satellite operators, Unicom USA) and another US firm, Rimsat. Rimsat now operates Gorizont spacecraft at 130, 134 and 142.5 degrees east longitude. Rimsat 1 is located at 134 degrees and has the ability to cover Australia – see Fig.1. In May this year, Rimsat was granted another two slots, at 70 degrees and 170.75 degrees east longitude, allowing coverage of most of Africa, Europe and the western United States. Until recently, the primary player in providing interna­ tional satellite communications was Intelsat, who launched their second satellite in 1966 over the Pacific ocean and their third satellite over the Indian ocean in 1969. In our area of interest, there are presently four Intelsat satellites over the Pacific and all are visible from the east coast of Australia using dishes of 3 metres or more but plenty of competition is on the way. Several private international operators now threaten the monopoly held by Intelsat. 60ø 30ø 0ø 30ø 60ø 60ø 90ø 120ø 150ø 150ø 180ø Fig.1: the footprint provided by Rimsat 1 (located at 134° East). Indonesia’s Palapa system Perhaps the first challenge to the Intelsat stronghold was Indonesia’s Palapa satellite system, launched in 1976. Originally designed to provide Indonesia with a basic telephone and tele­vision service, the original Palapa B1 satellite was purchased at the end of its predicted service life by a privately owned Indo­nesian company. The satellite was placed into an inclined orbit to conserve station keeping fuel and is now co-located with Rimsat 1. Palapa B1 is used to pro-vide lowcost communication links through­out Indonesia. At present there are three Palapa satellites in operation (B2P, B2R, & B4), serving Thailand, the Philippines, Papua New Guinea, Indonesia, UN forces in Cambodia, and Vietnam. The Aus­ tralian ABC has a transponder on the Palapa B2P satellite, carry­ing Fig.2: Palapa 1 covers most of South East Asia & also has extensive footprints over Australia & New Zealand. Other spacecraft in the series will also cover Australia. the Australian ATVI service, and will shortly add US CNBC programming to this schedule. The first of the new series C Palapa satellites is sched­uled for launch in 1995 and this will have a significant foot­print over Australia – see Fig.2. The present B series satellites require a 4 metre dish for reasonable reception on the south eastern coast of Australia. Another Intelsat competitor, Panam­sat, already has a fully loaded satellite, PAS-1, located over the July 1994  7 Fig.3: PAS-2 is configured with K & C band transponders. Signal levels covering Australia & New Zealand will allow the use of dishes 1.8-2.4 metres in diameter Atlantic ocean and will launch their second satellite PAS-2 as this article goes to press. PAS-2 is an HS-601 spacecraft, configured with K and C band downlink transponders. Signal levels covering Australia and New Zealand will allow the use of small dishes (1.8 metres to 2.4 metres in diameter) – see Fig.3. Asiasat 3.4m 3.7m (a) 1.2m 0.9m O.75m 0.75m 1.2m 0.9m (b) 39dBW EQUATOR 37dBW 34dBW 33dBW Asiasat 2, to be launched later this year, will provide strong signal levels in Australia. Good reception should be possible using dishes in the 1.8-metre diameter range. 8  Silicon Chip Another high profile operator, Asiasat, launched its first satellite in April 1990. Asiasat 1 is the refurbished Westar 4 US domestic satellite, originally launched in 1984 and subse­ quently retrieved by the Space Shuttle. This satellite is fully loaded with many premium services. Covering over 30 countries and an audience of 3 billion people (although not receivable in Australia), this is the satellite that started the Asian trans­ponder boom. Asiasat 2 will be launched late this year or early in 1995 and will be located at 100.5 degrees east longitude. The foot­print covering Australia indicates that small dishes in the 1.8 metre diameter range will provide good results from this satel­lite – see Fig.4. One of Asiasat’s fiercest competitors is the APT satellite company, a Beijing commercial company located in Hong Kong. Apstar 1, scheduled for launch later this year and to be located at 131 degrees east longitude, will provide signals covering most of Asia and the northern parts of Australia. The satellite is fully booked by the Chinese Ministries of Posts and regional TV broad­casters. The second satellite, Apstar 2, presently filed for a slot at 134 degrees east, is scheduled for launch in early 1995 and will cover all of Australia. The Australian ABC has reserved space on Apstar 1 and will transfer to Apstar 2 by mid 1995. Japan Satellite Systems Inc (JSAT) also has plans to launch a satellite in August 1995. This satellite will be a Hughes HS-601 with multiple beam coverage. Called JCSAT3, this bird will cover an area from India and Russia, to Australia, New Zealand and Hawaii. A special K band spot beam will be used to cover Australia and new Zealand. Apart from the four satellites operated by Intelsat in both the Pacific Ocean Region (POR) and the Indian Ocean region (IOR), a separate satel- lite, Intelsat 501, is located at 91.5 degrees east longitude, specifically to service the Asia Pacific region. This satellite, launched in 1981, is nearing the end of its life and will be replaced by Intelsat 805, to be launched by the China Great Wall Industry during 1995. It will be located at 87.5 degrees east longitude. Existing Gorizont series C band satellites continue to operate at 140 degrees east (Gorizont 18) and 96.8 degrees east (Gorizont 19). Gorizont 19 covers most of Australia and can be received along the east coast with a 1.8 metre dish. Winners of the Silicon Chip/Tektronix 1994 Reader Survey Optus B2 replacement The replacement for the Optus satellite B2 lost last year is likely to be launched using a Long March launch­er around September this year. It will replace the existing A2 satellite located at 164 degrees east longitude. A2 is presently in an inclined orbit, due to its low level of station keeping propel­lant, and serves as a backup for the Optus fibre optic network. This will ease the congestion on the B1 satellite and allow the release of transponders 10 and 11 on that unit for future pay TV operations. Optus is also reported to have filed an applica­ tion with the ITU for a fourth orbital slot at 151.5 degrees east longitude. This slot is proposed to be used for a digital audio broadcasting service, downlinking on L band (1452-1492MHz). Video compression One result of the increased demand for transponder space has been the acceleration of the finalisation of the MPEG 2 digital video compression standard. This new technique allows up to 10 digitally compressed TV signals to be downlinked using only one satellite transponder (at one tenth of the normal cost). Australian satellite delivered pay TV will use this transmission method, requiring a special “decompressor” to be used in conjunc­ tion with existing reception hardware. Many of the new satellites we have mentioned will no doubt migrate to this higher efficiency, lower operating cost transmis­sion system. Even if you disregard the new digital compression tech­niques though, the next few years will see an explosion of satel­ lite services aimed at SC Australia. Our second reader survey, carried in the January, February & March 1994 issues, had an unprecedented response. We are delighted that so many readers took the time to fill in all the questions and, in many cases, also wrote letters expressing their views. Winner of the first prize, a Tektronix TDS 310 2-channel digital storage oscilloscope with GPIB, RS-232 and Centronics interfaces, was Mr Kerry Power, 93 Beryl St, Coffs Harbour, NSW 2450. The second prize was a suite of Tektronix test equipment comprising a CPS250 triple output power supply, a CDM250 bench digital multimeter, a CFG250 2MHz function generator and a CFC250 100MHz frequency count­er. This was won by Mr Colin Mooney, 4 Anchorage St, Sea­ ford, SA 5169. The third prize was a Tektronix DM254 digital multimeter which      SILICON was won by Mr K. Eldridge, 1 Craigholm St, Sylvania, NSW 2224. Our thanks to all readers who participated in the survey and to Tektronix Australia Pty Ltd for sponsoring the competition. The response was unprecedented, with over 4000 surveys being returned by the due date. Full processing of the completed surveys is expected to take several months. Above: pictured is Mr Kerry Power with his son Daniel, receiving the Tektronix TDS310 digital oscilloscope from Alan Richards, senior sales engineer. CHIP BINDERS These beautifully-made binders will protect your copies of SILICON CHIP. To order, just fill in & mail the order form in this issue, or phone or fax your order to:     Silicon Chip Publications,      PO Box 139, Collaroy Beach, 2097.      Phone (02) 979 5644. Fax: (02) 979 6503. July 1994  9