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Wednesday, February 7, 2024

MIVAR 28M1 TVD YEAR 1994

 

 The MIVAR 28M1  TVD is a 28 inches color television with 40 programs PLL synthesized tuning and Bifonic 2 speakers mono sound and teletext.The teletext information is usually transmitted as part of the television signal in television lines where no normal television picture information is present. Initially, teletext transmissions in the United Kingdom used as teletext data lines television lines 17 and 18 in first fields and television lines 330 and 331 in second fields of the field or vertical blanking intervals (VBI), but current teletext transmissions in the United Kingdom now use at least six television lines in each VBI as data-lines. The VBI transmission is thus, in effect, multiplexed with the normal picture transmission and the teletext information transmitted in this way and representing data for display such as text and graphics can be displayed at a teletext television receiver as a selectable alternative to the normal picture information.

  • The MIVAR 28M1 TVD  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.


  • This model series was featuring a chassis design with a video section based around TDA8390A (PHILIPS) and was first and last using it.is a one-chip PAL colour decoder which is designed to be used in combination with the P’ CCD Delay Line (TDA8451) and the Filter Combination (TDA8452). The IC combines the circuits that are required for the identification and demodulation of PAL signals, RGB matrixing and amplification. SECAM signals can be handled when the IC is used in combination with the SECAM decoder TDA8490. Inductive components are not required due to the integration of the filters and the delay lines.
Therefore, no adjustments are required to the filters and delay times. The decoder
contains separate inputs for RGB signal insertion (analogue or digital) which can, for example, be used
for text display systems (e.g. channel number display, Teletext, Antiope etc.).

  • Was  last MIVAR Tv  using the TEA2029C + TEA2164 SYNCH + POWER SUPPLY DESIGN in their chassis design and these configurations gave a high level of tech to these sets far better than other tv brands and types.......

  • The set was featured with  VIDEOCOLOR MP CRT which first  time features  a color picture tube of the type having a shadow mask attached to a peripheral frame which is suspended in relation to a viewing screen of the tube, and particularly to such a tube having an improved shadow mask frame with reduced weight.

    As the sizes of color picture tubes have increased, there has been a corresponding increase in the sizes and weights of tube components. One of these components is the shadow mask frame. Present color picture tubes use steel frames to support the shadow masks within the faceplate panels of the tubes. One type of frame is made from a continuous piece of L-shaped steel, that is bent and welded to itself at its ends. Another type of frame is formed by pressing a flat steel sheet into the shape of the frame. A third type of frame is disclosed in Canadian Patent 988,141, issued to T. M. Shrader and K. A. Long on Apr. 27, 1976. This patent shows a frame that is formed from four pieces that are welded together at the four corners of the frame. The cited purpose of using four pieces is to provide an adjustable frame to precisely fit within a particular mask. Each of the four pieces has two flanges configured in an L-shaped cross-section. A first of the flanges extends toward a screen of the tube and a second flange extends from the first flange toward a central longitudinal axis of the tube. In each piece, the first flange extends beyond the second flange at both ends of the piece. These extensions of the first flange overlap each other in the corners of the frame and are where the pieces are welded together.

    The three frame types discussed above are usually supported within a faceplate panel by either three or four springs that are attached to the sides of the frames. Recently, large tubes have been suggested that are supported within faceplates by four springs located at the corners of the mask frame. The present invention provides a frame with reduced weight that can be used in a tube having corner support springs. 

     

    • 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.

These set were offering excellent bright and crisp pictures and good sound for a very fair price.

Bifonic 2 speakers sound + teletext and SCART socket are completing the main features.

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 !

 Furthermore they were very robust and easy to fix.


The cabinet is made of a high quality plastic which doesn't know age or degradation at all.


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

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 sqm which covered 30.000 meters , for the viabilit with parking spaces and 60,000 meters 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 ! ! !









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 when new - restoring in this time. 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 garbage:
  • The Propaganda TV Machine a.k.a. The Ministry of Truth delivers The Truth from The Government to the people.
At least, that's what they say. In fact, a Propaganda Machine is only employed by The Empire and used to brainwash people into Gullible Lemmings who believe that everything is all right when in fact, it isn't, and that the very people who could help them are their enemies..............

................... so the quality of the picture must be important........................ 

expecially for those football idiots so the they have the motivation to glue their assface on the screen all day long to discover better somewaht in their ignorance.
........Now................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 Blog would be taking part in the magnificent TELEVISION colour receiver project, but more likely restoring  monochrome receivers or adapting old color ones, if they were indifferent to the quality of the picture obtained at the end of the day. But today times seems changing, the trend started by many readers of Obsolete Technology Tellye !  have had a significative rise up in recovering and restoring old CRT's TV's and started to build up collections by people in many lands worldwide.
 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 restorer / 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, so you will find excellent sets from the 70s/80s. I 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 analog TV sets which may eventually but not certainly 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 times, with completely different technically means, reality where unfair market conditions focibly applied to European firms by an elite which has only the will and target to destroy European eritage at all levels with the main  point in destroying local economy.
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, manufacturing and materials in 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 heavy taxations, troublesome difficulties at all levels) and sold with medium to high prices respect to initial build costs !!
For that there can't be a comparation of reliability between a CRT TV SET and any one of todays sets, which often are resulting in a SCAM mainly under the technological part, emerging, even, from the first repair attempt !
......  And  in the end you will NEVER SEE a  restoring of ANY of the Actual todays electronic GARBAGE !


R.I.P.  EUROPE !


R.I.P CARLO !
 (Montieri, 5 febbraio 1923 – Milano, 20 settembre 2021).
 
On September 20 of the year 2021, at the age of 98, Mr. Carlo Vichi left us. 
The last will of him for the funeral ceremony were these: 
no authorities. 
A poor wooden coffin in the center of the plant 
with all the inhabitants of Abbiategrasso invited to a big party.
 
For all the good you have dispensed, he finally rests in peace.
 
 

 

    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.

 

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