SALORA 28M91 YEAR 1989.

 

TheSALORA 28M91  is a 28 inches (66cm) color television with stereo sound , 60 programs PLL synth tuning and teletext.

The SALORA 28M91 was first SALORA DIGITAL television featuring the ITT DIGIT2000.

The SALORA M91 model was a top-class stereo television  and was first  that came with digital NICAM stereo equipment. It also had e.g. full screen picture, meaning that the picture was sharp and clear in the corners too. In addition to this, it had picture-in-picture (PIP) function ADD-ON OPTION, instructional on-screen displays and digitally controlled text television with browsing and multiple page memory. The television had 140 channels and 60 memory locations.


To be noted that the Finnish broadcasting corporation began stereo and multi - sound transmissions for televisions with digital NICAM system in 1988. Transmissions had stereo sound and that made it possible to listen to programs either in Finnish or Swedish. Salora's experts team significantly influenced the selection of NICAM system as the Nordic standard.

The set is featuring one of the most complex TV CHASSIS of the world.

SALORA 28M91  Colour television receiver or set , are known in which the majority of signal processing that takes place therein is carried out digitally. That is, a video or television signal is received in a conventional fashion using a known analog tuning circuit and then, following the tuning operation, the received analog television signal is converted into a digital signal and digitally processed before subsequently being converted back to an analog signal for display on a colour cathode ray tube.
 The Salora M chassis was one of the first to appear in which signal processing and timebase waveform gener- ation are carried out digitally. As with other digital chassis, engineers tend to avert their eyes when one of them comes into the workshop. Once the back has been removed, you find lots of forty -pin ICs.

In a conventional television receiver, all signals are analog-processed. Analog signal processing, however, has the problems at the video stage and thereafter. These problems stem from the general drawbacks of analog signal processing with regard to time-base operation, specifically, incomplete Y/C separation (which causes cross color and dot interference), various types of problems resulting in low picture quality, and low precision of synchronization. Furthermore, from the viewpoints of cost and ease of manufacturing the analog circuit, a hybrid configuration must be employed even if the main circuit comprises an IC. In addition to these disadvantages, many adjustments must be performed.  So here's one or more advantage of digital operation.

Another is that the land cowboy down the road     or the master monkeyshine walking mud of the city full 1500$/Eur crap-i-phone + last rayban featured     or the common chimp-loud bike runner      or even the simple next door neighbour who is good at fixing pushbikes after some asking there and there on low life knowledgeable Internet Bullshit teeeechie Forums won't have messed thing up before you get there.

Bear in mind that with digital operation things don't need to be adjusted very often. So apart from the tube going low -emission or failure of an output stage we shouldn't have much to worry about. If only this were so! You are usually faced with a set that won't go at all. The "where do I start?" feeling returns pretty quickly.

In order to solve the above problems, it is proposed to process all signals in a digital form from the video stage to the chrominance signal demodulation stage. In such a digital television receiver, various improvements in picture quality should result due to the advantages of digital signal processing.
Therefore digital television signal processing system introduced in 1984 by the Worldwide Semiconductor Group (Freiburg, West Germany) of International Telephone and Telegraph Corporation is described in an ITT Corporation publication titled "VLSI Digital TV System--DIGIT 2000." In that system color video signals, after being processed in digital (binary) form, are converted to analog form by means of digital-to-analog converters before being coupled to an image displaying kinescope. The analog color video signals are coupled to the kinescope via analog buffer amplifiers and video output kinescope driver amplifiers which provide video output signals at a high level suitable for driving intensity control electrodes of the kinescope.

Digital Signal Processing DIGVISION ITT in Brief:

 FOR several years now the use of digital techniques in television has been growing. A considerable impetus came initially from the need for high -quality Tv standards conversion. The IBA's DICE (Digital Intercontinental Conversion Equipment) standards converter came into operational use in 1972. It's success demonstrated convincingly the advantages of processing video signals in digital form - digital signals are neither phase nor level dependent. The trend since then has been towards the all - digital studio: digital effects generators have been in use for some time, and digital telecines were announced earlier this year. An earlier example of the application of digital techniques to television was the BBC's sound-in-syncs system, in which the sound signal is converted to digital form so that it can be added to the video signal for network distribution. The sound-in-syncs system first came into use in 1969, and is was  widely employed in pay tv systems alongside with video scrambling methods in the 80's.  Digital techniques have already appeared on the domestic TV scene. The teletext signals are digital, and require digital processing. In modern remote control systems the commands from the remote control transmitter are in digital form, and require digital decoding and digital - to -analogue conversion in the receiver before the required control action can be put into effect. Allied to this, digital techniques are used for the more sophisticated channel tuning systems. The basic TV receiver itself continues to use analogue techniques however. Are we about to see major changes here? 
ITT Semiconductors in W. Germany have been working on the application of digital techniques to basic TV receiver signal processing since 1977 with the supervision of the Engineer Micic Ljubomir, and at the recent Berlin Radio Show presented a set of digital chips for processing the video, audio and deflection signals in a TV receiver. The set consists of a' couple of l.s.i. and six v.l.s.i. chips - and by very large scale integration (v.l.s.i.) we're talking about chips that contain some more 200,000 transistors. What are the advantages? 

For the setmaker, there's reduction in the component count and simpler, automated receiver alignment - alignment data is simply fed into a programmable memory in the receiver, which then adjusts itself. Subsequently, the use of feedback enables the set to maintain its performance as it ages. From the user's viewpoint, the advantages are improved performance and the fact that extra features such as picture -within -a -picture (two pictures on the screen at the same time) and still pictures become relatively simple to incorporate. The disadvantage of course is the need for a lot of extra circuitry. Since the received signals remain in analogue form, analogue -to -digital conversion is required before signal processing is undertaken. As the c.r.t. requires analogue drive signals, digital -to -analogue conversion is required prior to the RGB output stages - the situation is somewhat different in the timebase and audio departments, since the line drive is basically digital anyway and class D amplifier techniques can be used in the field and audio output stages. In between the A -D conversion and the various output stages, handling the signals in digital form calls for much more elaborate circuitry - hence those chips with 200,000 or so transistors. The extra circuitry is all incorporated within a handful of chips of course, but the big question is if and when the use of these chips will become an economic proposition, taking into account reduced receiver assembly/setting up costs, compared to the use of the present analogue technology - after all, colour receiver component counts are already very low. With the present digital technology, it's not feasible to convert the signals to digital form at i.f. So conversion takes place following video and sound demodulation. Fig. 1 shows in simple block diagram form the basic video and deflection signal processing arrangement used in the system devised by ITT Semiconductors. Before going into detail, two basic points have to be considered - the rate at which the incoming analogue signals are sampled for conversion to digital form, and the number of digits required for signal coding. Consider the example shown in Fig. 2. At both (a) and (b) the signals are sampled at times Ti, T2 etc. In (a) the signal is changing at a much faster rate than the sampling rate. So very little of the signal information would be present in the samples. In (b) the rate at which the signal is changing is much slower, and since the sampling rate is the same the samples will contain the signal information accurately. In practice, the sampling rate has to be at least twice the bandwidth of the signal being sampled. Once you've got your samples, the next question is how many digits are required for adequate resolution of the signal, i.e. how many steps are required on the vertical (signal level) scale in Fig. 2 The use of a four -digit code, i.e. 0000, 0001 etc., gives 16 possible signal levels. Doubling the number of digits to eight gives 256 signal levels and so on. ITT's experience shows that the luminance signal requires 8 bits (digits), the colour -difference signals require 6 bits, the audio signal requires 12 bits (14 for hi-fi quality) while 13 bits are required for a linear horizontal scan on a 26inch tube. These digital signals are handled as parallel data streams in the subsequent signal processing. Returning to Fig. 1, the A -D and D -A conversion required in the video channel is carried out by a single chip which ITT call the video codec (coder/decoder). A clock pulse generator i.c. is required to produce the various pulse trains necessary for the digital signal processing, and a control i.c. is used to act as a computer for the whole digital system and also to provide interfacing to enable the external controls (brightness, volume, colour etc.) to produce the desired effects. In addition, the control i.c. incorporates the digital channel selection system. The video codec i.c. uses parallel A-D/D-A conversion, i.e. a string of voltage comparators connected in parallel. This system places a high premium on the number of bits used to code the signal in digital form, so ITT have devised a technique of biasing the converter to achieve 8 -bit resolution using only 7 bits (the viewer's eye does some averaging on alternate lines, as with Simple PAL, but this time averaging luminance levels). The A -D comparators provide grey -encoded outputs, so the first stage in the video processor i.c. is a grey -to -binary transcoder. As Fig. 3 shows, the processes carried out in the video processor i.c. then follow the normal practice, though everything's done in digital form. The key to this processing is the use of digital filters. These are clocked at rates up to 18MHz, and provide delays, addition and multiplication. The glass chroma delay line required for PAL decoding in a conventional analogue decoder consists of blocks of RAM (random-access memory) occupying only three square millimeters of chip area each. As an example of the ingenuity of the ITT design, the digital delay line used for chroma signal averaging/separation in the PAL system is used in the NTSC version of the chip as a luminance/chrominance signal separating comb filter. Fig. 4 shows the basic processes carried out in the deflection processor i.c. This employs the sorts of techniques we're becoming used to in the latest generation of sync processor i.c.s. Digital video goes in, and the main outputs consist of a horizontal drive pulse plus drives to the field output and EW modulator circuits. The latter are produced by a pulse -width modulator arrangement, i.e. the sort of thing employed with class D output stages. The necessary gating and blanking pulses are also provided. A further chip provides audio signal processing. One might wonder why the relatively simple audio department calls for this sort of treatment. The W. German networks are already equipping themselves for dual -channel sound however, and the audio processor i.c. contains the circuitry required to sort out the two -carrier sound signals. These chips represent a major step in digitalizing the domestic TV receiver. It seems likely that some enterprising setmaker will in due course announce a "digital TV set". The interesting point then will be whether the chip yields, and the chip prices as production increases, will eventually make it worthwhile for all setmakers to follow this path (in 1984).

The SALORA 28M91   Is a multistandard set and relates to a digital multistandard decoder for video signals and to a method for decoding video signals.
Colour video signals, so-called composite video, blanking and sync signals (CVBS) are essentially composed of a brightness signal or luminance component (Y), two colour difference signals or chrominance components (U, V or I, Q), vertical and horizontal sync signals (VS, HS) and a blanking signal (BL).
The different coding processes, e.g. NTSC, PAL and SECAM, introduced into the known colour television standards, differ in the nature of the chrominance transmission and in particular the different systems make use of different colour subcarrier frequencies and different line frequencies.
The following explanations relate to the PAL and NTSC systems, but correspondingly apply to video signals of other standards and non-standardized signals.
The colour subcarrier frequency (fsc) of a PAL system and a NTSC system is fsc(NTSC) = 3.58 MHz or fsc(PAL) = 4.43 MHz.
In addition, in PAL and NTSC systems the relationships of the colour subcarrier frequency (fsc) to the line frequency (fh) are given by fsc(NTSC) = 227.50 * fh or 4•fsc(NTSC) = 910 • fh fsc(PAL) = 283.75 * fh or 4•fsc(PAL) = 1135 • fh so that the phase of the colour subcarrier in the case of NTSC is changed by 180°/line and in PAL by 270°/line.
In the case of digital video signal processing and decoding the prior art fundamentally distinguishes between two system architectures. These are the burst-locked architecture and the line-locked architecture, i.e. systems which operate with sampling frequencies for the video signal, which are produced in phase-locked manner to the colour subcarrier frequency transmitted with the burst pulse or in phase-locked manner with the line frequency, respectively.

The principal advantage of the present invention is a color television receiver is provided having a fully digital color demodulator wherein the luminance signal and the chrominance signals are separated and digitally processed prior to being converted to analog signals in that the all-digital signal processing largely eliminates the need for nonintegratable circuit elements, i.e., particularly coils and capacitors, and that the subcircuits can be preferably implemented using integrated insulated-gate field-effect transistor circuits, i.e., so-called MOS technology. This technology is better suited for implementing digital circuits than the so-called bipolar technology.

The SALORA 28M91    is a multisound tv digital sound processing.

It has a  DTI.(dti digital transient improvement pertains to a circuit for steepening color-signal transitions in color television receivers or the like particularly in DIGIVISION DIGIT2000 . ) circuit arrangement  designed for use in digital color-television receivers or the like and contains for each of the two digital color-difference signals a slope detector to which both a digital signal defining an amplitude threshold value and a digital signal defining a time threshold value are applied. At least one intermediate value occurring during an edge to be steepened is stored, and at the same time value of the steepened edge, it is "inserted" into the latter.
The bandwidth of the color-difference channel is very small compared with the bandwidth of the luminance channel, namely only about 1/5 that of the luminance channel in the television standards now in use. This narrow bandwidth leads to blurred color transitions ("color edging") in case of sudden color-signal changes, e.g., at the edges of the usual color-bar test signal, because, compared with the associated luminance-signal transition, an approximately fivefold duration of the color-signal transition results from the narrow transmission bandwidth.
In the prior circuit arrangement, the relatively slowly rising color-signal edges are steepened by suitably delaying the color-difference signals and the luminance signal and steepening the edges of the color-difference signals at the end of the delay by suitable analog circuits. The color-difference signals and the luminance signal are present and processed in analog form as usual. This circuit arrangement is designed for use in digital color-television receivers or the like and contains for each of the two digital color-difference signals a slope detector to which both a digital signal defining an amplitude threshold value and a digital signal defining a time threshold value are applied. At least one intermediate value occurring during an edge to be steepened is stored, and at the same time value of the steepened edge, it is "inserted" into the latter. This is done by means of memories, switches, output registers, and a sequence controller.
ADVANTAGE - Increased picture sharpness and highly improved signal-to-noise ratio.

The set has a pair of rotatable 2 way speakers box side located, see pictures.

The set has even 2 SCART SOCKETS and outputs for external loudspeakers.

A SCART Connector (which stands for Syndicat des Constructeurs d'Appareils Radiorécepteurs et Téléviseurs) is a standard for connecting audio-visual equipment together. The official standard for SCART is CENELEC document number EN 50049-1. SCART is also known as Péritel (especially in France) and Euroconnector but the name SCART will be used exclusively herein. The standard defines a 21-pin connector (herein after a SCART connector) for carrying analog television signals. Various pieces of equipment may be connected by cables having a plug fitting the SCART connectors. Television apparatuses commonly include one or more SCART connectors.

Although a SCART connector is bidirectional, the present invention is concerned with the use of a SCART connector as an input connector for receiving signals into a television apparatus. A SCART connector can receive input television signals either in an RGB format in which the red, green and blue signals are received on Pins 15, 11 and 7, respectively, or alternatively in an S-Video format in which the luminance (Y) and chroma (C) signals are received on Pins 20 and 15. As a result of the common usage of Pin 15 in accordance with the SCART standard, a SCART connector cannot receive input television signals in an RGB format and in an S-Video format at the same time.

Consequently many commercially available television apparatuses include a separate SCART connectors each dedicated to receive input television signals in one of an RGB format and an S-Video format. This limits the functionality of the SCART connectors. In practical terms, the number of SCART connectors which can be provided on a television apparatus is limited by cost and space considerations. However, different users wish the input a wide range of different combinations of formats of television signals, depending on the equipment they personally own and use. However, the provision of SCART connectors dedicated to input television signals in one of an RGB format and an S-Video format limits the overall connectivity of the television apparatus. Furthermore, for many users the different RGB format and S-Video format are confusing. Some users may not understand or may mistake the format of a television signal being supplied on a given cable from a given piece of equipment. This can result in the supply of input television signals of an inappropriate format for the SCART connector concerned.

This kind of connector is todays obsoleted !

Pictures, as any ITT DIGIT2000 DIGITAL chassis based, are superb and this set is featuring theTOSHIBA  CRT TUBE, which in other models  is also with TOSHIBA CRT TUBES.

The SALORA CHASSIS STB253 Chassis M here featured is a complex board with particular design in a way from POWER SUPPLY (IPSALO) to PCB 3 LAYER TYPE.

The Salora M chassis  horizontal deflection circuit for a television receiver is designed without a transformer so that the chassis is not voltage. The mains ac is rectified directly without a transformer and applied to a pump stage. The pump stage is coupled via a line transformer to the line output stage. Whilst the pump stage is connected electrically to the mains supply, the line output stage and the control circuits for the line output stage and for the pump stage are all electrically isolated from the ac mains. This isolation is achieved using three isolation transformers. Horizontal deflection circuits are used in conjunction with television picture tubes in television display devices. Typically, the horizontal deflection circuit includes a magnetic winding associated with the picture tube and a switching circuit by which energy from a direct voltage source is coupled to the winding and to its associated reactances. The switching circuit is synchronized with synchronizing signals associated with the information content of the video to be displayed on the picture tube. In order to avoid distorted images on the displayed raster, the size of the horizontal scanning line and the peak deflection or scanning current must be maintained constant over substantial periods of time. It is desirable to have a regulator scheme adaptable for use with a transistor deflection circuit which provides conductive isolation from the power mains, has no substantial voltage across the regulator switch during the retrace interval, a wide range of regulation, and which is commutated off and therefore has relatively small losses and which requires no independent turn-off circuit, or in which turn-off transients are small if a turn-off circuit is used. A regulated television deflection apparatus adapted to be energized by and isolated from a source of unregulated direct voltage includes a regulator switch having a controlled current path and a control electrode. A transformer has a primary winding serially coupled with the main current path and with the source of direct voltage for coupling energy from the source to the primary winding during those intervals in which the regulator switch is on. The transformer has a secondary winding conductively isolated from the primary winding. A deflection winding is coupled across the secondary winding for forming a path for the bidirectional flow of current therebetween. A trace switch is coupled in parallel with the deflection winding and is operated at the horizontal rate for promoting the flow of deflection current in the deflection winding during recurrent trace and retrace intervals. The voltage across the deflection winding during the retrace interval is coupled to the primary winding for reducing the current in the main current path to zero during the retrace intervals to turn the regulator switch off. A control circuit is coupled to the control electrode for controlling the time during the trace interval at which the regulator switch is turned on for maintaining the voltage or energy level associated with the deflection circuit at a substantially constant amplitude.

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An Increasingly Versatile Device The domestic television set used to be simply the thing that reproduced the programmes transmitted by one or other of the three programme networks  unless you happened to be connected to one of the wire systems that have experimented with local TV and pay TV at various times. But have you noticed what an increasingly versatile thing the TV set is becoming?
- The first major extension to the domestic TV set's possibilities came with the VCR, enabling you to record off air or replay prerecorded tapes. Domestic VTR systems have at a price  been with us for roughly a decade now, but till the advent of the easy to handle VCR most low-cost VTR systems were intended for use with monitors, with the signal interconnections at video and audio frequencies.
- Then came TV games, first found in the pubs and amusement arcades, later appearing in compact, relatively inexpensive packages for home use. The significant point here was the entry of digital techniques on the domestic TV scene. On the broadcast side, digital techniques had been making a substantial contribution to operations for some years, starting with the BBC's sound-in-syncs system (1969) in which the TV sound signal is compressed, converted to digital form and inserted in the line sync pulse period, and culminating with the IBA's famed DICE, which provides electronic standards (lines, fields, colour) conversion by converting the signals to digital form, processing them, then converting them back into analogue form.
Rather far from TV games you might think, but it's all part of the same process - the increasing impact of digital techniques on the world of television. In fact the technology of TV games has evolved considerably since their first appearance.
The approach then was to employ a fair number of standard digital i.c.s to build up the circuitry required. But why not go about it in the same way as the calculator manufacturers?
It didn't take long for the semiconductor people to see this new possibility for using their l.s.i. technology. This made it a relatively simple matter to provide a range of games with just a single i.c.  the basis of the present generation of TV games.
Add a second i.c. and the whole thing comes up in glorious colour. But it doesn't end there. The talk was now is of adopting microprocessor technology and making the system programmable, so that an almost unlimited range of games of varying degrees of complexity can be played. The favoured system seems to been to use prerecorded cassettes to provide the various programmes. And once you do that, you can extend the system to all sorts of other uses - teaching systems and so on. In fact you've made the TV set into part of a home computer installation - as we outlined in Teletopics last month. It's not impossible then to imagine some "viewers" using their TV sets for games, instruction and VCR use, while keeping up to date with teletext news and getting extra information via the PO's Viewdata system - and never watching a transmitted programme at all! We've come a long way then from the days of the TV set as a goggle

(goggle ????? or gooooooooooogle).................. box.
Teletext decoders and TV games were already being built into a few sets. What other digital innovations can we expect in TV sets? (may be DVB)
One now well established use of digital techniques is to provide all electronic channel selection.
The varicap tuner simply asks to be controlled in this way, and the system lends itself readily to remote control operation. Once you're controlling the tuner and generating various signals digitally there are other things you might as well do. Like flashing the selected channel number on the screen, or the time (coming shortly in Television!). Sets which do this sort of thing have been available on the Continent for some while now.
- The latest development along these lines is the picture within a picture a reduced size picture from another channel being inserted in the corner of the main display (PIP), so that you can watch two progrpnmes at once or see when to change over to a programme due to start on another channel. This involves some interesting digital processes - you've got to lose lines, and compact the video information by reading it into a memory at one speed and reading it out at another, in effect operating at two standards simultaneously while keeping both in sync (remember how difficult it has sometimes been to keep a set in sync on one standard!).
- There's only one thing that prevents a space-age TV installation in every home: cost.
But the cost of electronic hardware has a habit of falling dramatically once production has achieved a certain level. TV games are already commonplace, and teletext decoders have  become a lot cheaper once specialised i.c. modules for the purpose go into large scale production. From this point in time, it already seems that one can regard the days when the TV set simply displayed one of the programmes available as the age of stream TV.

....................................But we all know how it ended !

One more comment about digital in 2000..............

Over the years we have learnt that one of the most important things in video/ TV technology is selecting the best system to use. We have also seen how difficult this can be. Prior to the start of the colour TV era in Europe there was an great to-do about the best system to adopt. The US NTSC system seemed an obvious choice to start with. It had been proved in use, and refine- ments had been devised. But alternative, better solutions were proposed - PAL and Secam. PAL proved to be a great success, in fact a good choice. 

The French Secam system seems to have worked just as well. Apart from the video tape battles of the Seventies, the next really big debate concerned digital TV. When it came to digital terrestrial TV (DTT), Europe and the USA again adopted different standards. 

One major difference is the modulation system used for transmission. Coded orthogonal frequency   division multiplexing (COFDM) was selected for the European DVB system, while in the USA a system called 8VSB was adopted. COFDM uses quadrature amplitude modulation of a number of orthogonal carriers that are spread across the channel bandwidth. Because of their number, each carrier has a relatively low bit rate. 

The main advantage of the system is its excellent behaviour under multipath reception conditions. 8VSB represents a rather older,  pre phase modulation technoogy: eight  state amplitude modulation of a single carrier, with a vestigial sideband. The decision on the US system was assigned to the Advanced Television Systems Committee (ATSC), reporting to the FCC. The system it proposed was approved by the FCC on December 26th, 1996. The curious date might suggest that there had been a certain amount of politicking. In fact there had been an almighty row between the TV and computer industries about the video standard to adopt, the two fearing that one or other would gain an advantage as the technologies converged. It was 'resolved' by adopting a sort of   "open standard"  we are talking about resolution and scanning standards here - the idea apparently being that the technology would somehow sort itself out.

 There seems to have been rather less concern about the modulation standard. 8VSB was adopted because it was assumed to be able to provide a larger service area than the alternatives, including COFDM, for a given transmitter power. Well, the USA is a very large place! But the US TV industry, or at least some parts of it, is now having second thoughts. Once the FCC had made its decision, there was pressure to get on with digital TV. In early 1998 there were announce- ments about the start of transmissions and broadcasters assured the FCC that DTT would be available in the ten areas of greatest population concentration by May 1999. Rapid advances were expected, with an anticipated analogue TV switch -off in 2006. So far however things have not gone like that. At the end of 1999 some seventy DTI' transmitters were in operation, but Consumer Electronics Manufacturers Association estimates suggest that only some 50,000 sets and 5,000 STBs had been sold.

 There have been many reports of technical problems, in particular with reception in urban and hilly areas and the use of indoor aerials, also with video/audio sync and other matters. Poor reception with indoor aerials in urban conditions is of particular concern: that's how much of the population receives its TV. The UK was the first European country to start DTI', in late 1998 - at much the same time as in the USA. The contrast is striking. ONdigital had signed up well over 500,000 subscribers by the end of 1999, a much higher proportion of viewers than in the USA. Free STBs have played a part of course, but it's notable that DTT 's reception in the UK has been relatively hassle -free. In making this comparison it should also be remembered that the main aim of DTT technology differs in Europe and the USA. 

The main concern in Europe has been to provide additional channels. In the USA it has been to move to HDTV, in particular to provide a successor the NTSC system. There have been plenty of channels in the USA for many a year. For example the DirecTV satellite service started in mid 1994 and offers some 200 channels. Internationally, various countries have been comparing the US and European digital systems. They have overwhelmingly come down in favour of the DVB system. There have been some very damaging assessments of the ATSC standard. The present concern in the US TV industry results from this poor domestic take up and lack of international success. Did the FCC make a boob, in particular in the choice of 8VSB? Following compara- tive tests carried out by Sinclair Broadcasting Group Inc., the company has petitioned the FCC to adopt COFDM as an option in the ATSC standard. Not only did its tests confirm poor reception with indoor aerials: they also established that the greater coverage predicted for 8VSB failed to materialise in practice. Could the USA have two DTT transmission standards? It seems unlikely. It would involve dual standard receivers and non  standardisation of transmitters. In the all important business of system selection, it looks as if the FCC got it wrong.

              ....................................   It is obviously wasteful to duplicate terrestrial TV transmissions in analogue and digital form. Sooner or later transmissions will all be digital, since this is a more efficient use of spectrum space. The question is when? It would suit some to switch off the analogue transmitters as soon as possible. 2006 has been suggested as a time to start, with ana- logue transmissions finally ending in 2010. All very neat and tidy. Whether it will work out in that way is another matter. Strong doubts are already beginning to be aired. 

 The government has, quite properly, laid down conditions to be met before the switch off occurs. Basically that the digital signal coverage should equal that achieved for analogue TV, currently 99.4 per cent of the population, and that digital receiving equipment should be available at an affordable price. The real problem is that there is a difference between a coverage of 99.4 per cent and 99.4 per cent of the population actually having digital receiving equipment. Why should those who are interested in only free - to -air channels go out and buy/rent a digital receiver? It is already becoming evident that this represents a fair chunk of the population. 

The ITC has warned the government that the 2006-2010 timetable is in jeopardy. Peter Rogers, the ITC's chief executive, has said "we need to persuade people only interested in watching free -to -air television to switch to digital. "

Unless we do, there will be no switch - over." Well not quite, because the analogue receivers will eventually wear out and have to be replaced. But that could take a long, long time. Meanwhile many people will expect to be able to continue to watch their usual TV fare using their existing analogue receivers. 

Research carried out by Culture Secretary Chris Smith's department has established that between forty and fifty per cent of the population expects the BBC licence to cover their TV viewing, which means what they get at present in analogue form. A substantial percentage of the population simply isn't interested in going digital. In fact take up of integrated receiver -decoders, as opposed to the free digital set -top boxes, has so far been very slow. 

Of five million TV sets sold in the UK year 1999 , only 10,000 were digital. There are important factors apart from overall coverage and how many people have sets. There is the extension of coverage, which becomes more difficult to achieve eco- nomically as the number of those not covered decreases. There is the problem of reception quality. And there is the question of domestic arrangements and convenience. Extending coverage to the last ten fifteen per cent of the population by means of conventional terrestrial transmitters will be expensive. Mr Smith's department seems to have conceded that other methods of signal delivery may have to be adopted - by satellite, by microwave links or by cable. The latter has of course never been economic where few households are involved. 

The frequency planners have been trying to find ways of increasing coverage even to well populated areas. There are so many areas where problems of one sort or another make the provision of DTT difficult. Satellite TV is the obvious solution. 

The time may well come when it is wondered why anyone bothered with DTT. Signal quality is becoming an increasingly important factor as the digital roll out continues. In areas where the signal is marginal, viewers could experience the extreme irritation of picture break up or complete loss like even todays. This is quite apart from the actual quality of the channel, which depends on the number of bits per second used. There is a maximum number of bits per multiplex, the total being shared by several channels. The fewer the bits, the poorer the picture in terms of definition and rendering. 

There have already been complaints about poor quality. The question of domestic arrangements is one that has not so far received adequate public attention. Most households 2000 nowadays don't have just one TV set that the family watches. They have a main one, probably, almost certainly one or more VCRs, and several other sets around the house to serve various purposes. What 'the percentage of households that have digital TV' should really mean is the percentage willing to replace all this equipment. It will be expensive, and people would not be happy if they were told to throw away their other equipment when they get a single nice new all  singing all dancing widescreen digital TV set. It fact there would be uproar. The move from analogue to digital is not like that from 405 to 625 lines, which went fairly smoothly.

In those days few people had video equipment or a multitude of sets. The transition to digital is not going to be smooth, and the suggestion of a switch off during 2006-2010 already looks totally unrealistic. Unless the government subsidises or gives away digital TV sets - and why should it? - people will expect their existing equipment to continue to be usable.  

So it's likely that analogue TV will be with us for many years yet. But that would be the end of analogue too. 

.............................Indeed...............................

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History of Salora
History starts beginning 1928 in Salo (Finland), where Messrs Nordell and Koskinen built crystal receivers for the new Finish broadcasting station. Rapidly other radios followed, on battery and in 1930 on home electricity. In 1945, after WO II, the company was renamed SALORA oy. This name was a combination of the town SALO and the product RAdio. "Salora" grew and 15,000 radios were produced yearly by 300 people.

In 1957 Salora started the production of black/white TV-sets and in the beginning of the seventies, 2,000 people were employed and they built 1,000 TV-sets per day. At the end of the fifties they started the production of wireless phones for the army and the railways.

In 1966 the export of televisions to Sweden was starting and at the end of the seventies 60% of the production was destined for export. In 1978 a co-operation was founded with NOKIA – under the name MOBIRA – for the production of mobile phones.

In 1981 monitors for IBM were taken into production as well. Thereafter, in 1982, the mobile phone division was sold to NOKIA and in 1984 NOKIA bought the majority of the SALORA shares. In the same year SALORA started to make TV-sets for a famous Japanese brand for the total European market. In 1992 NOKIA took over SALORA completely.In February 2006 the brandname SALORA is being secured and from now on Albers Trading B.V. will supply her complete range of products under the name SALORA.