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Beosat AV

Manufactured: 1992 - 1994
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Satellite broadcasts in the UK began in 1989 with the introduction of 'BSB'. To accommodate this potential, different manufacturers released satellite equipment for reception of TV and radio programmes from space.

The transmissions were analogue in the early days; digital transmissions gradually took over until analogue reception came to a halt in 2000. Bang & Olufsen recognised customer interest in this new area and brought out Beosat: satellite equipment which could be added to an existing TV setup. Both a dish and a receiver were needed - Beosat RX was deliberately shaped to look like a video recorder in that it would fully match existing equipment. Bang & Olufsen's Parabolic Antennae were available in two sizes - 60cm and 91cm - in order to provide options for people who live where they could receive either strong or weak signals. The bigger of the two was for areas were satellite reception was not very strong.

A Positioner module, type no. 3012, was available as an installation accessory (see below right). The Positioner module controlled the polar mount motor that turned the dish towards another satellite, and the satellite positions could be stored with the programme number. Turning was then carried out automatically every time you switched to a programme from another satellite position. The Positioner module also contained the necessary power supply for the actuator motor on the outdoor unit.

A D2MAC decoder was available as an option for the Beosat LM, which made it possible to receive programmes in the D2MAC format. One of the benefits of this particular format was that it facilitated pay-TV with the addition of a card reader. This was used for programmes encrypted to the EuroCrypt M standard like 'FilmNet' and the Scandinavian satellite channel 'SCANSAT TV3'.

Features:

Internal mounting with only the socket panel visible at rear of TV set

Station naming and programme list

Reception of TV (including Teletext) and radio programmes with an exceptional sound quality

Rationalised tuning procedures

Comprehensive tuning facilities, video and audio tuning parameters stored on programme numbers

Control of outdoor units

Satellite signals could be relayed to extra TV sets

The fact that Beosat LM was an installation kit had a number of advantages including:

Interaction between the TV and the Beosat module which could be optimised both technically and operationally

The module shared the cabinet, power supply etc. with the Beovision, which meant, other things being equal, fewer components and better value for money

Building the satellite module into the TV gave an elegant video system, thus saving space without compromising technical performance.

Fully integrated operation

All operation was carried out on the Beolink terminal via the Beovision video master. Beosat LM and Beovision TV sets had a number of functions in common. For example, station naming was operated in the same way, as is Teletext functions.

Program list

The large number of satellite TV channels made it difficult to remember which channels are found on which programme numbers. The Programme List gave a convenient index of all stations when you committed their names to the station-naming memory. It consisted of a 5-page menu listing of all programme numbers with their programme names. On delivery Beosat LM was set up for reception for the reception of ASTRA analogue satellite transmissions, and all available TV and radio programmes was preset to ensure a convenient setup. As the programme names were also committed to the programme list memory, all satellite TV and radio functions were available as soon as the outdoor unit was installed and connected to the Beosat LM module.

The tuner

The tuner had a PLL (Phase Lock Loop) detector and was very sensitive to noise. It gave perfectly satisfactory reproduction with a lower signal level from the antenna (low threshold). This meant that in many areas a 60cm was able to be used.

Satellite audio/radio

Satellite TV sound is transmitted using a number of sub-carriers. Along with a mono sound channel, usually 6.65 MHz, up to eight sound channels could be transmitted for each satellite station, each on its own sub-carrier. Two of these sub-carriers could be used for transmission of stereo (if available), while others could be used for dual language transmission and/or radio programmes in the same quality. Separate FM modulated carriers were used for the left and right channels and in principle a channel separation of about 80dB could be obtained. So even though the technology involved was analogue, sound reproduction approached CD quality.

Satellite radio programmes could be reproduced through the Beovision speakers or via the audio system in a Beolink setup. Beosat LM could be programmed to receive satellite signals without a picture on the TV screen. Beosat LM was tuned to one of the sub-carriers, left channel, and the right channel was automatically tuned 180KHz higher. The low threshold tuner, together with a fast AFC function, provided for better sound with less noise. The sound reception quality was closely mirrored by the other elements in the video system, both with regard to reproduction and recording.

Tuning

It was generally more complicated to tune in to satellite TV stations than to terrestrial TV stations as there are more parameters to consider. However, in Beosat LM the tuning procedure was made easier by means of a carefully worked out operation, in which as many elements as possible were automated. Tuning could be carried out both directly on the remote control terminal and via on-screen menus. The direct tuning was typically used in simple setups (i.e. for the reception of TV/radio from a single satellite), while the menu tuning served all the many different tuning parameters in a straightforward and logical way - also if you wanted to receive from more than one satellite. Beosat LM was very versatile, and equally well-suited for all types of setups and consumer demands.

Direct tuning

Direct tuning can be said to be analogous to conventional Beovision tuning, either with automatic search or by keying in the frequency directly. For complex setups, e.g. with a motorised dish, the tuning menu was used. Direct tuning includes these parameters:

Frequency

Polarization

Fine-tuning

Station naming

Stereo or mono

Decoder

Reception parameters

The different tuning parameters were stored on the programme number, so when you switched to another programme Beosat LM automatically adjusted itself to the preset parameters. These are the video parameters that could be stored on individual program numbers:

Frequency

Band-switching

Polarisation-switching

Skew (with polar-rotor): fine-adjustment of polarisation when a polar mount was fitted

Video level. Most analogue satellites used a 25 MHz frequency deviation, whereas ASTRA analogue used 16 MHz. Video level adjustment adapted the contrast of programmes from different satellites to a uniform level

Dish position. A Positioner module could be installed to control the dish position for reception of programmes from different satellites

Decoder selection. For scrambled pay-TV programmes in which two Pay-TV decoders could be connected. They were programmed the same way as TV decoders. When a programme number with a decoder was selected, both for viewing, recording and timer recording, the signal was automatically looped through the decoder. The decoded programme could even be relayed to other rooms equipped with Local Control System

Fine-tuning. In addition to the video parameters the following sound parameters could be stored on programme numbers:

Sound selection: each satellite channel could be programmed to play mono or stereo sound when its programme number was selected. If mono sound was programmed, it could be switched to stereo with TURN, assuming the sound was transmitted in both mono and stereo. One mono and up to three stereo channels could be stored on a programme number

Sound frequency: mono and left/right sound channels in stereo signals are transmitted on separate frequencies, which must be stored. If you tuned to a station in video tuning mode, Beosat LM would also tune to the mono and stereo sound channels. For special purposes manual sound tuning was also available, via the sound tuning menu. The manual sound frequency range was 5.5 - 8.5 MHz

• Sound bandwidth: the three different sound bandwidths used in satellite transmission were available

• Sound de-emphasis

Created: 22nd January 2007
Modified: 7th February 2007

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