The MIVAR 22C1V is A 22 inches color television with 29 programs and PLL Synthesizer tuning system with RT15-99 control unit. A television tuning system employs a frequency synthesizer system for establishing the tuning of the receiver. A programmable frequency divider counter is connected between the output of a reference oscillator and a phase comparator to which the output of the local oscillator in the tuner also is applied. The phase comparator output provides a tuning voltage for controlling the tuning of the local oscillator. A microprocessor is used to control the count of the programmable frequency divider and initially to set a count corresponding to the selected channel in a counter connected between the output of the local oscillator and the phase comparator. The tuning consists of three discrete time periods. First, a settling time to allow channel change transients to settle; second, a short period of forced search at a relatively rapid rate to insure proper tuning; and third, a slower rate of step-by-step correction to accomodate for station drift and the like during reception. This third time period is initiated either by the passage of a fixed length of time following the start of the forced search period or by sensing a preestablished number of changes of state in the output of the frequency discriminator during the forced/search period.
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.
The set was first type sporting a chassis video section based around the PHILIPS TDA3562.The TDA3562A is a monolithic IC designed as decode PALand/or NTSC colour television standards and it combines all functions required for the identification and demodulationof PAL and NTSC signals.Furthermore it contains a luminance
amplifier, an RGB-matrix and amplifier. These amplifiers supply output signals up to 4 V peak-to-peak
(picture information) enabling direct drive of the discrete output stages.The circuit also contains separate
inputs for data insertion, analog and digital, which can be used for text display systems.FEATURES
• A black-current stabilizer which controls the black-currents of the three electron-guns to a level low
enough to omit the black-level adjustment
• Contrast control of inserted RGB signals
• No black-level disturbance when non-synchronized external RGB signals are available on the inputs
• NTSC capability with hue control.
The television set here shown was introducing a circuit arrangement for generating a sawtooth deflection current through a line deflection coil in an image display apparatus, which circuit arrangement comprises a deflection network including the deflection coil, a trace capacitor and a retrace capacitor and a first diode through which the deflection current flows during part of the trace interval whilst during the remainder of the trace interval this current flows through a second diode and a controllable switch, which switch and which second diode are connected in parallel with the first diode, the circuit arrangement further comprising an inductive element which is connected to the switch and is coupled to the deflection network via a third diode, and a transformer which has a core of a magnetic material and a winding of which is coupled, in series with a capacitor, to the deflection network.
Such a circuit arrangement is described in "IEEE Transactions on Broadcast and Television Receivers," August 1972, volume BTR-18, Nr. 3, pages 177 to 182, and is a combination of a line deflection circuit and a switched-mode supply voltage stabilizing circuit, the controllable switch being used to perform both the said functions. This known circuit arrangement has the advantage that it can be fed with an unstabilised supply voltage and is capable of supplying a satisfactorily stabilized deflection current, a stabilized high voltage and, if desired, auxiliary voltages, the stabilization being obtained by control of the conduction time of the swtich.
The set features a PHILIPS 30AX SYSTEM CRT.The 30AX system, which Philips introduced in 1979, is an important landmark in the development of colour picture systems. With previous systems the assembly technician had to workthrough a large number of complicated setting-up procedures whenever he fitted a television picture tube with aset of coils for deflecting the electron beams. These procedures were necessary to ensure that the beams for the three colours would converge at thescreen for every deflection. They are no longer necessary with the 30AX system: for a given screen format any deflection unit can be combined with any tube to form a single 'dynamically convergent' unit. A colour-television receiver can thus be assembled from its components almost as easily as a monochrome receiver. The colour picture tube of the PHILIPS 30AX system displays a noticeably sharper picture over the entire screen surface. This will be particularly noticeable when data transmissions such as Viewdata and Teletext are displayed. This has been achieved by a reduction in the size of the beam spot by about 30%. Absence of coma and the retention of the 36.5 mm neck diameter have both contributed to increased picture sharpness. Coma has been eliminated by means of corrective field shapers embedded in the deflection coils which are sectionally wound saddle types. The new deflection unit has no rear flanges. enabling uniform self-convergence to be obtained for all screen sizes. without special corrections, adjustments, or tolerance compensations. Horizontal raster distortion is reduced and no vertical correction is required. One of the inventions in 30AX is an internal magnetic correction system which obviates static convergence and colour purity errors. This enables the usual multiple unit to be dispensed with. together with the need for its adjustment ! New techniques have been employed to achieve close tolerance construction of the glass envelope. In addition, the 30AX picture tube incorporates two features whereby it can be accurately adjusted during the last stages of manufacture. One is the internal magnetic correction system. The other is an array of bosses on the cone that establish a precise reference for the axial purity positioning of the deflection unit on the tube axis and for raster orientation. During its manufacture, each deflection unit is individually adjusted for optimum convergence. The coil carrier also incorporates reference bosses that co-operate with those on the cone of the tube. ' Since every picture tube and every deflection unit is individually pre-aligned, any deflection unit automatically matches with any picture tube of the appropriate size. The deflection unit has only to be pushed onto the neck of the tube unit it seats. Once the reference bosses are engaged, the combination is accurately aligned and requires no adjustment for convergence, colour purity or raster orientation. With no multiple unit and a flangeless deflection unit, there is more space in the receiver cabinet. Higher deflection sensitivity means that less current is consumed, and consequently less heat is produced. This increases the reliability of the TV receiver again. 30AX means simple assembly. Any picture tube is compatible with any deflection unit of the appropriate size and is automatically self-aligning as well as being self-convergent.
The well-known 20AX features of HI-Bri, Soft-Flash and Quick-vision are maintained in the new 30AX systern. In their work on the design of deflection coils in the last few years the developers have expanded the magnetic deflectionfields into 'multipoles', This approach has improved the understanding of the relations between coil and field and between field and deflection to such an extent that designing deflection units is now more like playing a difficult but fascinating game of chess than carrying out the obscure computing procedure once necessary.
These sets were sold at fair price and they were good quality made and they last long.
These set were offering great features and extreme simplicity toghether and even combined with reliability and durability.
(Basically all what today you won't see anymore !)
In 1982 and in previous times MIVAR society name was Radio VAR then converted definitely to MIVAR.
In ancient times MIVAR was even a radios constructor, then the interest dropped to only television manufacturing.
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.
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.
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 ! ! !
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