BRIONVEGA TVC2250CD YEAR 1975.

The BRIONVEGA TVC2250CD is a 22 inches color television with 12 programs potentiometers tuned and ultrasonic remote control.

Was featuring a front led display showing program numbering.

Its the First BRIONVEGA Color TV set completely based on semiconductors and first and last using Thyristors technology in Horizontal deflection output circuits. And last using Delta Gun CRT tube. It has a  picture tube apparatus employing the so-called delta gun  shadow mask  The present invention relates to a color television picture tube  type color cathode-ray tube which is provided with three electron guns positioned respectively at the vertices of an equilateral triangle, " the so-called delta gun  shadow mask ".

To obtain a fine color picture on the screen of the cathode-ray tube of this type, the following requirements should be satisfied that the electron beam is emitted from each electron gun onto the center of each corresponding phosphor dot on the screen of the cathode-ray tube, the purity of colors is high and the electron beams are converged onto a group of phosphor dots.
These requirements can be comparatively easily satisfied in the case of the cathode-ray tube with a spherically formed screen, whereas it is difficult to satisfy the requirements in the case of a narrow-necked, wide-angle deflection cathode-ray tube. The wide angle deflection cathode-ray tube is advantageous in practical use because the distance between the electron guns and the screen is small and the screen is almost flat with a curvature approximate to that of a flat surface; however, it is necessary to control the electron beams so that the electron beams may be emitted exactly onto the 3-color phosphor dots on the screen because the incident angle and distance of the electron beams which reach the phosphor dots on the screen have the values proper to respective phospher dots.

 
Where such apparatus as television receivers are to be controlled from a viewer location as to channel, volume, brightness, etc., the remote control systems usually are made up of a hand held transmitter which transmits an ultrasonic signal to a receiver connected to or built within the television receiver. The depression of buttons on the transmitter causes a variety of signals or signal frequencies to be transmitted, whereby channel change, volume change, etc. is responsively obtained.
However such systems have individually suffered from one or more problems, such as inability to have direct access to the desired channel, slow access, insufficient noise immunity making it often possible to operate the system with the jingling of a key chain or an ultrasonic sound originating from a dishwasher etc., unreliable control due to the absence of means to detect and suppress transmission errors resulting from echoes, interfering signal sources, etc. Also some control systems are not suitable for continuous analog commands such as volume, brightness, etc. Existing systems also often require the need for bandpass filters and accurate crystal oscillators which make them costly. Many systems are not very suitable for integration into custom integrated circuits.
The present invention provides a remote control system whereby the nature of the remote control signal allows utmost reliability of control. The remote control receiver will be found to be virtually immune to echoes and ambient ultrasonic noises, and therefore will not produce a false response in the presence of echoes and ultrasonic interfering signals. A variety of kinds of commands can be provided, and with the preferred embodiment disclosed, up to ninety-nine channels in a television receiver can be instantaneously selected, without the requirement for sequentially stepping through each channel. Volume can be varied or muted, tint or brightness controlled, etc.
The above advantages are obtained by the transmission of a unique type of two tone coded signal which advantageously contains information defining start-up transmitted data, type of command (i.e. channel select identification or miscellaneous command such as volume), information permitting reconstruction of clock and identification of end of data. The two tones are transmitted sequentially. The second tone is transmitted to provide masking of echoes produced by the first tone and to mask noises that may be present in the operating environment of the system.
Since the two tones may be close together in frequency, it is possible to operate the remote control system in conjunction with high sensitivity resonant type microphones, thereby achieving high sensitivity together with high noise immunity. This also eliminates the need for input bandpass amplifiers.
The inventive receiver is thus rendered immune from operation by extraneous noise further by the provision of received data error checking circuitry for the timing of input pulses, etc., and for rejecting the data if an error is detected. The receiver also has provision for operation of continuous analog circuits in a television set, such as brightness, volume and tint controls, etc. Since echoes are masked out in the present system, data transmission can occur much more rapidly than in prior systems, as the receiver does not have to wait until echoes die out between transmission of bits for identification of data pulses.
Since all that is frequency dependent is the detection of signal above or below a predetermined reference frequency, accurate crystals for timing and reference frequency generation are not needed. The receiver is virtually entirely digital logic, making it suitable for monolithic integration with a minimum of external components. CMOS integrated circuit logic is preferred, minimizing power supply requirements.
In the preferred embodiment, two digits are transmitted separately and the second must be received within a given time interval, or the first number is disregarded. This method eliminates the need for a clear key as normally present on calculators.
The output of the receiver is a binary or BCD signal which can be used by known means to control the frequency of a selected channel, or to perform other functions such as variation of volume, control of brightness, tint, etc. in a television set.
It should also be understood that the use of this invention is not intended to be restricted to a television set, but can be utilized for the control of a large variety of other kinds of apparatus, e.g. door locks, household appliances, radio receivers, production machinery, etc. While the description below will be directed to a wireless ultrasonic transmitter-receiver system, it should be understood that a wired system, a radio control system, etc. could be used in the alternative.
The advantages of the invention are obtained by the provision of a system including means for receiving a transmitted signal comprising a pulse envelope modulated continuous wave ultrasonic signal at a first predetermined frequency, each pulse being immediately followed by a continuous wave ultrasonic signal at a second predetermined frequency which has amplitude such as to mask echoes of the first predetermined frequency at the receiving means, the pulses being representative of a sequence of binary bits, means to determine whether the received signal is above or below the frequency of a reference frequency, means for recognizing a change in input frequency with respect to the reference frequency, and means for counting said changes, determining the value of the binary bits, and providing a parallel coded signal representative of said value.

- Horizontal Beam Deflection  and high voltage generating circuits realized with Thyristors circuits.

The massive demand for colour television receivers in Europe/Germany in the 70's  brought about an influx of sets from the continent. Many of these use the thin -neck (29mm) type of 110° shadowmask tube and the Philips 20AX CRT Tube, plus the already Delta Gun CRT . 

Scanning of these tubes is accomplished by means of a toroidally wound deflection yoke (conventional 90° and thick -neck 110° tubes operate with saddle -wound deflection coils). The inductance of a toroidal yoke is very much less than that of a saddle -wound yoke, thus higher scan currents are required. The deflection current necessary for the line scan is about 12A peak -to -peak. This could be provided by a transistor line output stage but a current step-up transformer, which is bulky and both difficult and costly to manufacture, would be required. 

An entirely different approach, pioneered by RCA in America and developed by them and by ITT (SEL) in Germany, is the thyristor line output stage. In this system the scanning current is provided via two thyristors and two switching diodes which due to their characteristics can supply the deflection yoke without a step-up transformer (a small transformer is still required to obtain the input voltage pulse for the e.h.t. tripler). The purpose of this article is to explain the basic operation of such circuits. The thyristor line output circuit offers high reliability since all switching occurs at zero current level. C.R.T. flashovers, which can produce high current surges (up to 60A), have no detrimental effects on the switching diodes or thyristors since the forward voltage drop across these devices is small and the duration of the current pulses short. If a surge limiting resistor is pro- vided in the tube's final anode circuit the peak voltages produced by flashovers seldom exceed the normal repetitive circuit voltages by more than 50-100V. This is well within the device ratings.  It's a very good system to use where the line scan coils require large peak currents with only a moderate flyback voltage  an intrinsic characteristic of toroidally wound deflection coils. The basic thyristor line output stage arrangement used in all these chassis is shown in Fig. 1
it was originally devised by RCA. Many sets fitted with 110°, narrow -neck delta -gun tubes used a thyristor line output stage - for example those in the Grundig and Saba ranges and the Finlux Peacock , Indesit, Siemens, Salora, Metz, Nordmende, Blaupunkt, ITT, Seleco, REX, Mivar, Emerson, Brionvega, Loewe, Galaxi, Stern, Zanussi, Wega, Philco. The circuit continued to find favour in earlier chassis designed for use with in -line gun tubes, examples being found in the Grundig and Korting ranges - also,  Indesit, Siemens, Salora, Metz, Nordmende, Blaupunkt, ITT, Seleco, REX, Mivar, Emerson, Brionvega, Loewe, Galaxi, Stern, Zanussi, Wega, Philco the Rediffusion Mk. III chassis. Deflection currents of up to 13A peak -to -peak are commonly encountered with 110° tubes, with a flyback voltage of only some 600V peak  to peak. The total energy requirement is of the order of 6mJ, which is 50 per cent higher than modern 110° tubes of the 30AX and S4 variety with their saddle -wound line scan coils.   The only problem with this type of circuit is the large amount of energy that shuttles back and forth at line frequency. This places a heavy stress on certain components. Circuit losses produce quite high temperatures, which are concentrated at certain points, in particular the commutating combi coil. This leads to deterioration of the soldered joints around the coil, a common cause of failure. This can have a cumulative effect, a high resistance joint increasing the local heating until the joint becomes well and truly dry -a classic symptom with some Grundig / Emerson sets. The wound components themselves can be a source of trouble, due to losses - particularly the combi coil and the regulating transductor. Later chassis are less prone to this sort of thing, partly because of the use of later generation, higher efficiency yokes but mainly due to more generous and better design of the wound components. The ideal dielectric for use in the tuning capacitors is polypropylene (either metalised or film). It's a truly won- derful dielectric - very stable, with very small losses, and capable of operation at high frequencies and elevated temperatures. It's also nowadays reasonably inexpensive. Unfortunately many earlier chassis of this type used polyester capacitors, and it's no surprise that they were inclined to give up. When replacing the tuning capacitors in a thyristor line output stage it's essential to use polypropylene types -a good range of axial components with values ranging from 0.001µF to 047µF is available from RS Components, enabling even non-standard values to be made up from an appropriate combination. Using polypropylene capacitors in place of polyester ones will not only ensure capacitor reliability but will also lower the stress on other components by reducing the circuit losses (and hence power consumption).
       Numerous circuit designs for completely transistorized television receivers either have been incorporated in commercially available receivers or have been described in detail in various technical publications. One of the most troublesome areas in such transistor receivers, from the point of View of reliability and economy, lies in the horizontal deflection circuits.
       As an attempt to avoid the voltage and current limitations of transistor deflection circuits, a number of circuits have been proposed utilizing the silicon controlled rectifier (SCR), a semiconductor device capable of handling substantially higher currents and voltages than transistors.
       The circuit utilizes two bi-directionally conductive switching means which serve respectively as trace and commutating switches. Particularly, each of the switching means comprises the parallel combination of a silicon controlled rectifier (SCR) and a diode. The commutating switch is triggered on shortly before the desired beginning of retrace and, in conjunction with a resonant commutating circuit having an inductor and two capacitors, serves to turn off the trace switch to initiate retrace. The commutating circuit is also arranged to turn oft the commutating SCR before the end of retrace. 


The set is build with a Modular chassis design because as modern television receivers become more complex the problem of repairing the receiver becomes more difficult. As the number of components used in the television receiver increases the susceptibility to breakdown increases and it becomes more difficult to replace defective components as they are more closely spaced. The problem has become even more complicated with the increasing number of color television receivers in use. A color television receiver has a larger number of circuits of a higher degree of complexity than the black and white receiver and further a more highly trained serviceman is required to properly service the color television receiver.
Fortunately for the service problem to date, most failures occur in the vacuum tubes used in the television receivers. A faulty or inoperative vacuum tube is relatively easy to find and replace. However, where the television receiver malfunction is caused by the failure of other components, such as resistors, capacitors or inductors, it is harder to isolate the defective component and a higher degree of skill on the part of the serviceman is required.
Even with the great majority of the color television receiver malfunctions being of the "easy to find and repair" type proper servicing of color sets has been difficult to obtain due to the shortage of trained serviceman.
At the present time advances in the state of the semiconductor art have led to the increasing use of transistors in color television receivers. The receiver described in this application has only two tubes, the picture tube and the high voltage rectifier tube, all the other active components in the receiver being semiconductors.
One important characteristic of a semiconductor device is its extreme reliability in comparison with the vacuum tube. The number of transistor and integrated circuit failures in the television receiver will be very low in comparison with the failures of other components, the reverse of what is true in present day color television receivers. Thus most failures in future television receivers will be of the hard to service type and will require more highly qualified servicemen.
The primary symptoms of a television receiver malfunction are shown on the picture tube of the television receiver while the components causing the malfunction are located within the cabinet. Also many adjustments to the receiver require the serviceman to observe the screen. Thus the serviceman must use unsatisfactory mirror arrangements to remove the electronic chassis from the cabinet, usually a very difficult task. Further many components are "buried" in a maze of circuitry and other components so that they are difficult to remove and replace without damage to other components in the receiver.
Repairing a modern color television receiver often requires that the receiver be removed from the home and carried to a repair shop where it may remain for many weeks. This is an expensive undertaking since most receivers are bulky and heavy enough to require at least two persons to carry them. Further, two trips must be made to the home, one to pick up the receiver and one to deliver it. For these reasons, the cost of maintaining the color television receiver in operating condition often exceeds the initial cost of the receiver and is an important factor in determining whether a receiver will be purchased.
Therefore, the object of this invention is to provide a transistorized color television receiver in which the main electronic chassis is easily accessible for maintenance and adjustment. Another object of this invention is to provide a transistorized color television receiver in which the electronic circuits are divided into a plurality of modules with the modules easily removable for service and maintenance. The main electronic chassis is slidably mounted within the cabinet so that it may be withdrawn, in the same manner as a drawer, to expose the electronic circuitry therein for maintenance and adjustment from the rear closure panel after easy removal. Another aspect is the capability to be serviced at eventually the home of the owner.

BRIONVEGA  TVC2250CD is a product of the Italian designer Mario Bellini, Born in 1935, Mario Bellini studied at the Polytechnic in Milan, where he got his doctorate in 1959. He opened his studio in 1959, and worked frequently for Olivetti since 1963. Many of his designs can be found at the Museum of Modern Art in New York, where in 1987 a special exhibition was held of his work. He received a "Compasso d'Oro" in 1986. He worked for companies such as Artemide, B&B Italia, Cassina, Erco, Rosenthal, Ideal Standard, Poltrona Frau etc.. Mario Bellini is not only an outstandig industrial designer, his architecture is of the same consistent quality.

And furthermore in BRIONVEGA worked:

Richard Sapper was born in Munich in 1932. He studied philosophy, graphic design, engineering and economics. From 1956 - 1958 he worked for Mercedes Benz until he moved to Milan, where he worked with Marco Zanuso for Brionvega. Other companies he worked for are Siemens, Fiat, Pirelli IBM and Alessi. His most famous design is the Tizio lamp for Artemide. He was a professor at the Hochschule fuer Angewandte Kunst in Vienna. He received the "Compasso d'Oro" 5 times.



Brionvega is (was) an Italian electronics company, established in Milan in 1945.

Vega, BP Radio, Brionvega, Brion & Pajetta; Milano, Lissone (MI) (I)
Abbreviation: vega
Products: Model types
Summary: Society B.P.M. (1945) Vega - BP Radio (Fabbrica Apparecchi e Accessori Radio, Perito Ind. Brion & Ing. Pajetta)
Via Pacini 59, Milano (1948)
Via Ampère 61, Milano (ca. 1950)
Brionvega Formenti Sèleco Spa
Via Dante Alighieri 43, 20035 Lissone / MI

Good design is no longer simply for an "elite" but is demanded by a far wider audience interested in continuous development.With so many designs and products available, how is it possible to distinguish a truly outstanding design from one that is simply trendy. World famous designers: Hannes Wettstein, Mario Bellini, Richard Sapper, Marco Zanuso, Castiglioni brothers and Ettore Sottsass, have tried to come up with the answer to what constitutes the perfect design. In finding inspiration, when designing for Brionvega, these people look beyond every day fashion and look for examples which are outstanding in their beauty. They also pay attention to people's attitude and how they relate to everyday objects.


Historically speaking, Brionvega is one of the most famous radio and Television manufacturers, thanks to its products, born from the collaboration with well-known design firms. Over the years, from its establishment, Brionvega has made some industrial design corner-stones, such as the radio "cube" TS502 from 1963, the Algol and Doney portable TV, and the radio-phonograph RR126.

The BRIONVEGA stylish design is well recognized around the world for it's particularity.
The television here in collection The BRIONVEGA  TVC2250CD  is a clear example of that style.

References:

^ "Ex Sèleco a un imprenditore udinese", Articolo del Messaggero Veneto del 18 febbraio 2010

"Brionvega History". Brionvega.tv. Retrieved 18 February 2012.
  "2008 Brionvega reissues". brionvega.tv.
 
"Cuboglass TV History". brionvega.it.