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Monday, February 3, 2014

MIVAR 21C2L STEREO YEAR 1988.






The MIVAR  21C2L STEREO is An easy 21 inches color stereo television set with teletext.

Even if it is a "plastic thing" the quality of this is superb and stable and far superior to other brands even highly more expensive.

The set has 30 programs PLL synthesized  tuning and remote MIVAR TC3, the television tuning system employs a frequency synthesizer system for establishing the tuning of the receiver, featured with a Microcomputer driven synthesis system, coupled to a frequency lock controller chip such as a Philips TSA5511 / SIEMENS SDA3202. This tuner can tune television signals on VHF and UHF band. Recently, frequency synthesizers including a phase locked loop (PLL) have been suggested to accurately generate local oscillator signals at predetermined frequencies corresponding to the various channels which a viewer may select.
The system employed in the tv permits utilization of a frequency synthesizer tuning system which correctly tunes to a desired television station or channel even if the transmitted signals from that station are not precisely maintained at the proper frequencies even in combination of a fine tuning adjustable by the user.To enable operation of the receiver in a fringe area, where it may be desirable to intentionally mistune a channel slightly, manual fine tuning control logic circuitry is employed to disable the frequency offset logic circuit and to permit changing the count of the reversible counter by the viewer to manually fine tune the receiver as desired.
Accordingly, it is an object of this invention to provide an improved tuning system for a television receiver.
It is an additional object of this invention to provide an improved frequency synthesizer tuning system for a television receiver.

+ Av SCART socket + stereo hifi sound + teletext and remote + front stereo headphones jack.
Teletext is a television-based communication technique in which a given horizontal video line is utilized for broadcasting textual and graphical information encoded in a digital binary representation. Such horizontal video line signal that contains teletext data is referred to herein as a Data-line. It is assumed herein, for explanation purposes, that teletext is sent by the broadcaster only during the vertical blanking interval (VBI), when no other picture information is sent. The organization of the binary information in the broadcast signal is determined by the standard employed by the broadcaster. By way of an example only, references are made herein to a teletext based on a standard referred to by the British Broadcasting Corporation (BBC) as CEEFAX.

Each Data-line carries data synchronizing and address information and the codes for a Row of 40 characters. The synchronizing information includes a clock run-in sequence followed by an 8-bit framing code sequence. Each Data-line contains a 3 bit code referred to as the Magazine number. A teletext Page includes 24 Rows of 40 characters, including a special top Row called the Page-Header. Each ROW is contained in a corresponding Data-line. A user selected Page is intended to be displayed in place of, or added to a corresponding television picture frame. A Magazine is defined to include Pages having Data-lines containing a corresponding Magazine number. The transmission of a selected Page begins with, and includes its Page Header and ends with and excludes the next Page Header of the selected Magazine number. All intermediate Data lines carrying the selected Magazine number relate to the selected Page.
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 !
The set here shown like other Mivar tv's was introducing a novelty in power supply design;Switch-mode power supply with burst mode standby operation:
In a typical switch mode power supply (SMPS) of a television receiver the AC mains supply voltage is coupled to a bridge rectifier. An unregulated direct current (DC) input supply voltage is produced. A pulse width modulator controls the duty cycle of a chopper transistor switch that applies the unregulated supply voltage across a primary winding of a flyback transformer. A flyback voltage at a frequency that is determined by the modulator is developed at a secondary winding of the transformer and is rectified to produce DC output supply voltages such as a voltage B+ that energizes a horizontal deflection circuit of the television receiver and a voltage that energizes a remote control unit.
During normal operation, the DC output supply voltages are regulated by the pulse width modulator in a negative feedback manner. During standby operation, the SMPS is required to generate the DC output supply voltage that energizes the remote control unit. However, most other stages of the television receiver are inoperative and do not draw supply currents. Consequently, the average value of the duty cycle of the chopper transistor may have to be substantially lower during standby than during normal operation.
Because of, for example, storage time limitation in the chopper transistor, it may not be possible to reduce the length of the conduction interval in a given cycle below a minimum level. Thus, in order to maintain the average value of the duty cycle low, it may be desirable to operate the chopper transistor in an intermittent or burst mode, during standby. During standby, a long dead time interval occurs between consecutively occurring burst mode operation intervals. Only during the burst mode operation interval switching operation occurs in the chopper transistor. The result is that each of the conduction intervals is of a sufficient length.
In accordance with an aspect of the invention, burst mode operation intervals are initiated and occur at a rate that is determined by a repetitive signal at the frequency of the AC mains supply voltage. For example, when the mains supply voltage is at 50 Hz, each burst mode operation interval, when switching cycles occur, may last 5 milliseconds and the dead time interval when no switching cycles occur, may last during the remainder portion or 15 milliseconds. Such arrangement that is triggered by a signal at the frequency of the mains supply voltage simplifies the design of the SMPS.
The burst mode operation intervals that occur in standby operation are synchronized to the 50 Hz signal. During each such interval, pulses of current are produced in transformers and inductances of the SMPS. The pulses of current occur in clusters that are repetitive at 50 Hz. The pulses of current occur at a frequency that is equal to the switching frequency of the chopper transistor within each burst mode operation interval. Such qurrent pulses might produce an objectionable sound during power-off or standby operation. The objectionable sound might be produced due to possible parasitic mechanical vibrations as a result of the pulse currents in, for example, the inductances and transformers of the SMPS.
In accordance with another aspect of the invention, the change in the AC mains supply voltage during each period causes the length of the conduction interval in consecutively occurring switching cycle during the burst mode operation interval to increase progressively. Such operation that occurs during each burst mode operation interval may be referred to as soft start operation. The soft start operation causes, for example, gradual charging of capacitors in the SMPS. Consequently, the parasitic mechanical vibrations are substantially reduced. Also, the frequency of the switching cycles within each burst mode operation interval is maintained above the audible range for further reducing the level of such audible noise during standby operation.
A switch mode power supply, embodying an aspect of the invention, for generating an output supply voltage during both a standby-mode of operation and during a run-mode of operation includes a source of AC mains input supply voltage. A control signal at a given frequency is generated. A switching arrangement energized by the input supply voltage and responsive to the first control signal produces a switching current during both the standby-mode of operation and the run-mode operation. The output supply voltage is generated from the switching current. An arrangement coupled to the switching arrangement and responsive to a standby-mode/run-mode control signal and to a signal at a frequency that is determined by a frequency of the AC mains input supply voltage controls the switching arrangement in a burst mode manner during the standby-mode of operation. During a burst interval, a plurality of switching cycles are performed and during an alternating dead time interval no switching cycles are performed. The two intervals alternate at a frequency that is determined by the frequency of the AC mains input supply voltage.

This model series was very reliable and durable with an excellent fair buy price at the time.

The MIVAR  21C2L STEREO  WAS / is far more sophisticated than all others equivalent sets at the time and is the 21 inches format after the MIVAR 28C2L STEREO YEAR 1989.

The remote control was the MIVAR TC3 for all functions.

The MIVAR 21C2L STEREO  was first Mivar tvc featuring a Videocolor FS10 CRT Tube in small format (21 inches - 51cm and a 111° CRT TUBE)  square screen black matrix improved electron gun focusing crt tube, An improved color picture tube has an inline electron gun for generating and directing three electron beams, a center beam and two side beams, along coplanar paths toward a screen of the tube. The gun includes a main focus lens for focusing the electron beams. The main focus lens is formed by two spaced electrode members, each having three separate inline apertures therein, a center aperture and two side apertures. The improvement comprises each of the apertures in each of the focus lens electrodes having a shape that distorts a portion of the focus lens thereat, to at least partially compensate for an astigmatic effect within the tube that acts on an associated electron beam. The side apertures in both of the electrodes are nonsymmetrical about axes that pass through the respective side apertures and are perpendicular to the initial coplanar paths of the electron beams. furthermore the gun includes an additional accelerator electrode after G2 directly connected to HV ultor voltage .The gun includes a plurality of electrodes which form a beam-forming region, a prefocusing lens, and a main focusing lens for the electron beams. The prefocusing lens includes four active surfaces. At least one of the active surfaces has asymmetric prefocusing recesses formed therein.

It's made by MIVAR an Italian Brand NO MORE ACTIVE In television manufacturing.


A brief note about on Television sets reliability and durability..........................

ANYONE with even the smallest experience of television engineering is bound to come up against that embarrassing question which is always so difficult to answer-"which TV shall I get?" The questioner is usually concerned about obtaining the cheapest and most reliable receiver that is available, and this same approach generally governs the choice between buying and renting. This is perfectly reasonable and often applies to other consumer products apart from TV. What does seem a little strange however is that no one ever seems to ask "which TV set gives the best picture?" Why not? Doesn't anyone care, or is the question too complicated to discuss? Yet the average person spends five and a half hours a day, every day, watching TV: so the quality of the picture must be important. 
It is high time that people began to realise this simple fact, and to take an interest in the quality of the product that absorbs so much of their spare time. There are of course plenty of people who are genuinely interested in good picture quality. It is unlikely for example that so many readers of this journal would be taking part in the magnificent TELEVISION colour receiver project, building new monochrome receivers or adapting old ones, if they were indifferent to the quality of the picture obtained at the end of the day. Good CRT  picture quality cannot however be achieved merely by connecting together the appropriate groups of circuits. Sometimes in fact even well established designs can present problems if they are assembled in a different way to the original or with non-standard components. So what constitutes good picture quality and what do you do when things go wrong? It is not much use delving into the textbooks because they are strangely unhelpful about this sort of thing.  At least however we can here at Obsolete Technology Tellye !  establish some basic principles to use as a starting point. There is a difference between the kind of picture quality defects that you would expect to find in a manufactured receiver compared to one made by a home constructor. A CRT manufactured receiver usually has only minor faults and one wants to'assess how well it compares with the products of other set - makers.Todays trade, threw a rather different light on matters however. Briefly, we found that during CRT boom periods for the setmakers reliability increased whilst during periods of diminishing sales a fall in the standard of reliability became evident. We had tended to think that a boom meant an attitude of anything goes to get as many sets out to meet the demand, with consequent corner cutting and use of whatever alternative components could be got hold of if necessary. The overriding point seems to be however that in boom conditions with a seller's market prices can be maintained and quality standards kept up whilst in flat market conditions there is overwhelming pressure on prices and reliability tends to fall. It is difficult to be too sure about this since the worst trading period coincided with the era of dual standard TV sets which may eventually inevitably less reliable than the single -standard chassis which preceeded and succeeded them. It would however tie up  about the comparative reliability of colour and monochrome sets, since the era of colour boom coincides with a very flat period in monochrome set production and sales, that in talking about reliability means overall dependability rather than initial statistics for unboxed set condition. That all said is very applicable to todays, completely technically different, reality were unfair market conditions applied to European firms by an elite which has only the will and target to destroy European eritage in and  all levels. It includes a number of areas of law involving acts by one competitor or group of competitors which harm another in the field, and which may give rise to criminal offenses and civil causes of action.Trade libel, the spreading of false information about the quality or characteristics of a competitor's products, is prohibited at common law but still high present and unstopped.Various unfair business practices such as fraud, misrepresentation, and unconscionable contracts may be considered unfair competition, if they give one competitor an advantage over others expecially all from the so called ASIATIC MARKET.

Therefore:
All of todays apparates are literally absolute GARBAGE when new and resulting often broken when out of the box after purchase. Poor engineering and materials the main part, combined with unfair massive import to Europe of such DUMP goods, at cheap prices in closed hard tight market (so they can be the only 2 3 competitor in foreign lands and all locals firms brought to death by taxations, difficulties at all levels)
For that there is NO comparable reliability between a CRT TV SET and any one of todays sets, which often resulting a SCAM even under the technological part, emerging from the first repair attempt !

MIVAR Sets have had great features and extreme simplicity toghether with compactness and combined with reliability and durability.
(Basically all what today you won't see anymore !)


It's made by MIVAR an Italian Brand no more active since 20/12/2013.


MIVAR is a Factory site in the near of Milan (italy) in a Industrial city conglomerate called Abbiate Grasso.

Founded in 1945 by Mr. Carlo Vichi class of 1923, The activity started in 1945 - in Milano, Via Ugo Tommei 5 street with fabrication of little radio apparates.


HISTORY OF MIVAR.

1945 - Milan, Via Ugo Tommei 5: Begin the activity
assembling small radios.


1950 - Via Curtatone 12: developed with the construction of more direct major radio components fabricants.

1956 - 13 Street Strigelli: industrial production is manily targeted to first radio devices with frequency modulation (FM).

1958 - Via P. 30 Jordanians: TV become a reality, the industries is doubling his ACTIVITY, always in Milan, we build the first "real" plant with 400 employees.

1963 - Abbiategrasso, Via Dante 45: in the wake of decentralization and the rampant success of the television, building a facility that will become important in place 800 employees occupying between 1968-70.

1990 - Abbiategrasso Canal towpath: aware of the physiological importance that television plays in society? Modern, rich expertise and resources, we began construction of a factory area of ​​120,000 m? which covered 30.00o , for the viabilit with parking spaces and 60,000 park trees.

In origin the factory was brand named as Radio Var and indeed the tellye here in collection is internally marked as Radio VAR. After 1985 they were marked rightly MIVAR.
Today's activity is oriented in virtual production of LCD crap but with very low market penetration due to "unfair" asian competitors presence and a local governement which don't care about.

(You call it global
market, I call it WORLD DESTRUCTION combined toghether with mass Afro scum crap Immigration (EUROPEAN INVASION) to obtain destruction on a large scale in all places and to help more and better the loose of all OUR workplaces and firms , lives, people).



 “If our buildings, our highways, and our railroads should be wrecked, we could rebuild them.

If our cities should be destroyed, out of the very ruins we could erect newer and greater ones.

Even if our armed might should be crushed, we could rear sons who would redeem our power.


Anyway Obsolete Technology Tellye will show even this model as a Time machine which looses nothing of the good tellyes ! ! !







    Further Notes:

^ "MIVAR: tutto iniziò in via Tommei", articolo tratto dal sito quattronet.it Archiviato il 14 novembre 2011 in Internet Archive.^ [Maker], Mivar ; Milano from Audiphon to Trader, 703 pictures, 124 sc, su www.radiomuseum.org. URL consultato il 13 giugno 2018.^ NUOVO ASSALTO AL CARROZZONE REL - la Repubblica.it, in Archivio - la Repubblica.it. URL consultato l'11 gennaio 2018.^ LA MIVAR FA UTILI SENZA SPENDERE PER LA PUBBLICITA' - la Repubblica.it, in Archivio - la Repubblica.it. URL consultato l'11 gennaio 2018.^ MIVAR, MIRACOLO AD ABBIATEGRASSO - la Repubblica.it, in Archivio - la Repubblica.it. URL consultato l'11 gennaio 2018.^ Archivio Corriere della Sera, su archiviostorico.corriere.it. URL consultato l'11 gennaio 2018.^ Archivio Corriere della Sera, su archiviostorico.corriere.it. URL consultato l'11 gennaio 2018.^ notizia del sito Adnkronos del 4 maggio 2005 Archiviato il 19 ottobre 2006 in Internet Archive.^ JOB MILANO, in archive.is, 10 dicembre 2012. URL consultato l'11 gennaio 2018 (archiviato dall'url originale il 10 dicembre 2012).^ Mivar rilancia in Full Hd - Il Sole 24 ORE, su www.ilsole24ore.com. URL consultato l'11 gennaio 2018.^ (IT) Mivar In Crisi Ma Il Riscatto Avverrà Con I Led, su www.paid2write.org. URL consultato l'11 gennaio 2018.
MonrifNet, Televisori Mivar: fine dei programmi il 30 novembre - Il Giorno - Legnano, su www.ilgiorno.it. URL consultato l'11 gennaio 2018.
^ “La mia Mivar chiude, l’affitto gratis a chi assume 1200 italiani”, in Fanpage. URL consultato l'11 gennaio 2018.

R.I.P CARLO !
(Montieri, 5 febbraio 1923 – Milano, 20 settembre 2021).

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