BRIONVEGA VOLANS 17" VR.S1 YEAR 1974.

The BRIONVEGA VOLANS 17" VR.S1  is  a Portable  17 inches B/W television with 6 programs push button selection and potentiometric tuning search system.
The mechanical turret approach to television tuning has been used almost exclusively for the past 60 years. Even though replete with the inherent disadvantages of mechanical complexity, unreliability and cost, such apparatus has been technically capable of performing its intended function and as a result the consumer has had to bear the burdens associated with the device. However, with the " recent "  Broadcast demands for parity of tuning for UHF and VHF channels, the increasing number of UHF and cable TV stations have imposed new tuning performance requirements which severely tax the capability of the mechanical turret tuner. Consequently, attempts are now being made to provide all electronic tuning to meet the new requirements.


The invention relates to a tuning unit with bandswitch for high frequency receivers, especially radio and television receivers, having a potentiometer system for the control of capacity diodes, the said potentiometer system consisting of a plurality of parallel resistance paths along which wiper contacts can be driven by means of screw spindles disposed adjacent one another in a common insulating material housing in which a bandswitch formed of metal rods is associated with each tuning spindle.
In these tuning units, the working voltages of the capacity diodes in the tuning circuits are recorded once a precise tuning to the desired frequency has been performed. A potentiometer tuning system has great advantages over the formerly used channel selectors operating with mechanically adjustable capacitors (tuning condensers) or mechanically adjustable inductances (variometers), mainly because it is not required to have such great precision in its tuning mechanism.
Tuning units with bandswitches formed of variable resistances and combined with interlocking pushbuttons controlling the supply of recorded working voltages to capacity diodes are known. Channel selection is accomplished by depressing the knobs, and the tuning or fine tuning are performed by turning the knobs. The resistances serving as voltage dividers in these tuning units are combined into a component unit such that they are in the form of a ladderlike pattern on a common insulating plate forming the cover of the housing in which the tuning spindles and wiper contacts corresponding to the variable resistances are housed. The number of resistances corresponds to the number of channels or frequencies which are to be recorded. The wiper contact picks up a voltage which, when applied to the capacity diodes determines their capacitance and hence the frequency of the corresponding oscillating circuit. The adjustment of the wipers is performed by turning the tuning spindle coupled to the tuning knob. By the depression of a button the electrical connection between a contact rod and a tuning spindle is brought about and thus the selected voltage is applied to the capacity diodes. Since the push buttons release one another, it is possible simply by depressing another button to tune to a different receiving frequency or a different channel, as the case may be.



In the end of the 60's increasingly attention was focused on the varicap diode tuner as the latest, sophisticated means of television receiver frontend tuning in both colour and black and white sets.

The main purpose of this article is to investigate the servicing problems associated with this comparatively new method of tuning.


First however let's briefly recap on the principles involved in this tuning system:


The tuners use variable capacitance (or "varicap") diodes as the variable tuning elements: the effective capacitance of the diodes is controlled by the reverse bias applied across them, tuning being achieved by varying this voltage. As the reverse bias across a varicap diode is increased so its junction depletion region widens thus reducing its capacitance.

A VHF/ UHF television tuner is constructed in accordance with the present invention includes a preselector tuned circuit having a solid state voltage controlled capacitor as its tunable element, a radio frequency amplifier coupled to the preselector circuit and alsoother circuit to perfect the signal receiving capability and the application the like.


Considering the Mechanical Tuner Problems:


To get the servicing problems in perspective let us next consider the tuning arrangements previously used.

The earliest of these, employed on v.h.f., was the switched tuner which was either of the turret or incremental type.

The turret tuner substituted a coil bearing "biscuit" mounted on the rotating drum or turret when channels were changed. Twelve positions were normally provided, with a fine tuning knob to adjust the local oscillator frequency. As its name suggests the incremental tuner simply added more inductance to the tuned circuits at every downward channel movement: thus the highest inductance was present on channel one and the least on channel 12 (which normally covered 13 as well with manipulation of the fine tuner).

The movement towards u.h.f. TV working, initially with dual standard sets and later with single standard ones, brought about the need for u.h.f. tuners. In the earliest u.h.f. receivers valve tuners which were not particularly efficient were used.


The drive mechanism was usually a dual speed rotary system calibrated from channels 21 to 68. Experience in the field indicated that 625 line television was in many cases considered by the viewer to be inferior to 405 -line reception, on account of the poor signal to noise ratio achieved by the valve tuners. Many viewers were not prepared to use external u.h.f. aerials of course, having achieved satisfactory reception on v.h.f. with an indoor aerial: this aggravated the situation even more.

Another aspect which caused difficulty was the care needed to tune in a u.h.f. channel using a rotary tuner covering the whole of Bands IV and V. Many viewers simply could not tune in BBC 2 or ZDF or ORF or any channel correctly with such a tuning mechanism, finding that they had passed right over the channel they wanted before realising what they had done.

The advent of transistor tuners rapidly improved the quality of u.h.f. reception but use of a rotary mechanism was continued by many manufacturers. Thus while potential reception was improved the same tuning difficulties remained and viewers continued to gravitate towards 405 line viewing using the "old faithful" switched tuner. The operational breakthrough came with the introduction of the push-button u.h.f. channel change.


The mechanism is basically simple. Adjustable push buttons press down on a lever bar which in turn rotates the tuner's variable capacitors to the appropriate position. Each button is capable of tuning over the entire u.h.f. bands and this leads to customer confusion at times when after some adjustments which were too heavy handed they find themselves receiving ITV on a BBC button or a ORF and ZDF broadcasting or any channel possible !


Mechanical Faults:


Mechanical tuning obviously has its snags. There are for example contact springs which earth the tuning capacitor and go intermittent. This gives rise to the most random tuning defects, capable of driving the. most patient viewer to a state of total exasperation. It is also possible for the rotation mechanism to hang up and jam intermittently, or just become sticky, so that the reset accuracy of the mechanism is impaired and the receiver has to be retuned every time the channel is changed.

The vanes in the tuning capacitor can also short out at different settings, thereby eliminating some channels. The Varicap Tuner It will be seen then that mechanical defects can cause very irritating fault symptoms. If one thinks along the lines that anything mechanical is nasty, then the elimination of mechanical parts can only be to the good.


The logic of this is splendid provided the electronic replacement for the mechanical system is more reliable! Otherwise we are leaping out of the frying pan into the fire! In the light of experience gained with mechanical tuning devices it seems great that with the varicap tuner we have at last dispensed with the dreaded rotary tuning capacitor, replacing it instead with a variable voltage to the tuner.

Let us think about this however since things are never quite as simple as they first appear. The tuning voltage has to be variable in order to tune the receiver. Obviously then a means of varying the voltage has to be provided to act as the tuning control.

As it is a voltage that has to be varied the tuning control takes the form of a potentiometer., Now we have returned to a mechanical system again, though in a less complex form.

A potentiometer is required for each channel, selected by pressing the appropriate channel button.


We have lost a tuning capacitor and its rotating mechanism and gained a set of pots and selector switches therefore. Provided the pots and switches are mechanically more reliable than the tuning capacitor we should be better off-or should we?


Need for Voltage Stabilisation.

The voltage selected by the pots cannot be allowed to drift otherwise the receiver will go off -tune. The voltage supply to the potentiometers has to be stabilised therefore and a stabilising zener diode or integrated circuit (TAA550) .is needed for this purpose.


Any failure in this part of the circuit will give rise to tuning drift or worse, a total loss of reception. A short-circuit TAA550 for example will completely remove the tuning voltage while if it is open circuit the tuning can vary with picture brightness. Likewise any intermittency in the potentiometers or associated switching and/or resistors can also cause problems.


Relative Reliability of Tuners:


It will be seen then that in order to lose our troublesome mechanical arrangement we have had to introduce considerably more electronics which we trust are going to be more reliable. In addition we have not so far considered the relative reliability of the varicap tuner itself compared with the mechanical type. Since two r.f. transistors are generally used to compensate for the reduced Q of the varicap tuned circuits we immediately have twice the likelihood of an r.f. stage breaking down!

And being semiconductors the varicap diodes themselves are more likely to fail than the sections of a ganged tuning capacitor. It is reasonable then to conclude that if mechanical faults are the most prevalent the use of varicap tuners will make life easier. Mechanical faults are generally not too difficult to sort out however and the field engineer can often cope with them in the home.

Can the same be said of the varicap tuner? It seems that this type of tuner does not need so much attention as its mechanical counterpart but is likely to throw up some much more difficult faults when it does, resulting in bench repairs being needed. So far my own experience has indicated that varicap tuning faults nearly always need servicing on the bench.

Generally speaking it seems true to say that varicap tuners themselves are adequately reliable: the snags result from the tuning system and stabilised power supply.


Tuning Drift with Varicap Tuners:


If a varicap tuned receiver is constantly drifting off tune the +30V supply should be the number one suspect. It is best to connect an Avometer permanently to the supply so that it can be precisely monitored-if necessary write down the exact voltage measured.

If the receiver drifts, check the voltage. If it has changed, even slightly, this may well be enough to be the cause of the fault. To pinpoint and confirm the diagnosis aerosol freezer should be applied to the stabiliser i.c. or zener. If the voltage returns to normal or changes wildly for the worse the stabiliser is almost certainly the cause of the trouble and should be replaced.

A prolonged soak test should then be carried out. Another point concerning varicap tuners arises with their use in colour receivers.

 There were  makers of the most expensive colour receiver on the market still didn't use a varicap tuner but instead use a mechanical one. The makers' claim is that the signal to-noise ratio of the varicap tuner is inadequate for their colour standards. Undoubtedly the results obtained on the receiver seem to confirm this. Interestingly, the same manufacturers use varicap tuners in their black -and -white receivers, and the tuning button system is often full of troublesome intermittent contacts. The varicap tuner has its advantages and disadvantages then. Probably the simplest comment would be to say that when it is good it is very very good but when it is bad it is horrid!

Springs component in old tv's tuner :
Most old televisions tuning mechanisms were incorporating coil springs in one form or another for various functions. They can be of the compression type which are wound with spaces between adjacent turns and are intended to be squeezed under pressure : when released they expand to their original form. The mounting springs under record-player turntable units are examples of this type. Alternatively the spring can be of the expanding variety. The coils are wound closely together with adjacent turns touching. The applied tension tends to pull them apart and they exert a contracting force to counteract this and pull the linked components together. In the majority of applications this type is used. Springs often become damaged by being over stretched, or the end loop breaks. More frequently the spring simply becomes detached and disappears. Thus the engineer is faced with the task of finding and fitting a replacement. While it is possible to apply to the makers of the equipment for the right spring this involves delay and of course there is always the problem of identifying the right one out of the many used in the particular mechanism. For this reason many engineers find it more convenient to make their own replacements.

Making a Coil Spring: The operation was quite simple, the equipment needed being a wheelbrace, vice, selection of long screwdrivers with varying diameter shanks and a supply of piano wire of various gauges. The wheelbrace is mounted horizontally in the vice with the wheel uppermost and a screwdriver chosen and inserted into the chuck with the blade foremost. This serves as a mandrel on which the spring can be wound. Because a spring expands slightly in diameter after it is wound the diameter of the screwdriver shank should be a little less than the required inside diameter of the spring. One end of the piano wire should be inserted in the chuck and secured to prevent it coming free. The wheel is then slowly turned and the wire taken up around the screwdriver shank. Keep the wire taut and pull it backward (see Fig. 1) toward the chuck at an angle which keeps the adjacent turns together but does not make a turn ride over the top of its predecessor. When the spring has reached the required length cut the wire and remove the springand screwdriver from the chuck.
As an aid in determining the size of the spring required-especially if the original is lost and there is no pattern to make a comparison with-here are a few observations on the characteristics of coil springs as determined by their dimensions.
Properties of Coil Springs: There are two main properties of a spring, the length to which it can be expanded in comparison to its closed length and its tension or strength in the expanded state. If a coil spring is expanded too far its coils will not return to their original position and the spring is said to be stretched. The amount that a spring can be expanded without becoming stretched is governed by the number of turns and the diameter. The greater the number of turns the less each one has to deviate from its resting position for the complete spring to reach a particular length. Also the greater the diameter the smaller the strain and therefore the more the spring can be expanded. The strength of a spring is related to the gauge of wire and the diameter. A heavy gauge will obviously give greater tension than a lighter one but also a spring with a large diameter will exert less force than a smaller one because as we have seen there is less strain when it is expanded. More force is exerted when the spring is well expanded than when it is nearly closed. If therefore we need a spring that is strong and will stretch a long way we need a large number of turns but not so many that the spring is too long in its closed position. It needs to be of fairly large diameter but as this will make it weaker we must compensate by using a heavy gauge of wire. A weak spring with a long stretch is easily made with thinner wire and a large diameter while a strong spring with a short stretch need have few turns and small diameter. So the various factors are interdependent and although spring design can be quite an exact art-by varying the various parameters-something suitable for the job can usually be made up by judicously estimating the size from the foregoing principles. If a spring has become stretched nothing can be done to restore it by squeezing it up as it has now become a compression spring and the expanded state is its normal one. Rather than winding a completely new spring however the old one can be unwound on a wheelbrace-by reversing the winding process and then rewound tightly. Proper unwinding is essential, not just pulling the spring out straight, because this will produce kinks.
Leaf Springs: From coil springs we turn to leaf springs. These were used as contacts in tuner units and are also were used in the press  button channel selector of the Philips colour TV range and other fabricants. To make a positive contact the leaf spring must be tensioned just right. In the case of the turret tuner the leaf must be so sprung that the contacting stud moves it about a tenth of an inch away from the resting position. If as sometimes happens contact is made without much movement of the leaf there will be little if any pressure and the contact will very likely be intermittent. If on the other hand the leaf is adjusted too far forward it may be caught by the edge of the coil biscuit and crumpled when the turret is rotated.

 Moreover, using this arrangement, the only indication--during adjustment--of which channel is selected is by station identification.

Tuning button are under small fins lid.
It has a Transistorized horizontal deflection circuits  made up of a horizontal switching or output transistor, a diode, one or more capacitors and a deflection winding. The output transistor, operating as a switch, is driven by a horizontal rate square wave signal and conducts during a portion of the horizontal trace interval. A diode, connected in parallel with the transistor, conducts during the remainder of the trace interval. A retrace capacitor and the deflection yoke winding are coupled in parallel across the transistor-diode combination. Energy is transferred into and out of the deflection winding via the diode and output transistor during the trace interval and via the retrace capacitor during the retrace interval.
In some television receivers, the collector of the horizontal output transistor is coupled to the B+ power supply through the primary windings of the high voltage transformer.

The  BRIONVEGA VOLANS 17" VR.S1  was first "VOLANS" model with a tuning keyboard with 6 programs instead of earlier types with rotary VHF and UHF tuners.

The set was allowing multiple supply mains voltages tankfully to a voltage changer combined with an internal autotransformer.

Further supply was a 24volt DC with special socket, see pictures.

An external speaker was connectable too.

The  BRIONVEGA VOLANS 17" VR.S1 is designed by Mario Bellini.

Mario Bellini (born February 1, 1935, Milan) is a world renowned Italian architect and designer. He graduated from the Milan Polytechnic - Faculty of Architecture in 1959 and began working as an architect himself in the early 1960s. He is the winner among others of 8 Compasso d’Oro and prestigious architecture awards including the Medaglia d’Oro conferred on him by the President of the Italian Republic.

Like many other Italian architects, his activities range from architecture and urban planning to product and furniture design.

His early international success grew rapidly during the first two decades, especially in the design sector, and reached its peak in 1987 with the greatest acknowledgement expressed in a personal retrospective exhibition at the Museum of Modern Art of New York, which at the time already included 25 of his works in its Permanent Collection, including a remarkable set of Olivetti machines as well as the furniture for B&B and Cassina - such as the famous "Cab" chair - and the innovative office chairs designed for Vitra. His career as a product and furniture designer began in 1963. From 1963 to 1991 he was chief design consultant for Olivetti. For many years he designed furnishing products and systems for B&B Italia and Cassina, TV sets for Brionvega, and hi-fi systems and electric organs for Yamaha. For 5 years he worked as an automobile design consultant with Renault. In 1972 he was commissioned to design and build the prototype of the Kar-a-Sutra mobile environment for the exhibition “Italy: the New Domestic Landscape” at the Museum of Modern Art in New York. He has also designed for Fiat and Lancia (notably the interior of the 1980 Lancia Trevi), lamps for Artemide, Erco and Flos, and office furniture for Vitra. Other firms for whom he has designed and/or continues to design products include (in Italy) Acerbis, Bras, Driade, Candy, Castilia, Flou, Kartell, Marcatrè, Meritalia, Natuzzi and Poltrona Frau; (in Belgium) Ideal Standard; (in Germany) Lamy and Rosenthal; (in Japan) Fuji and Zojtrushi; and (in the USA) Heller. MBA's headquarters of some 1,500 sq.m in Milan were designed by Mario Bellini himself in the early 1990s, and today an average of 30 to 35 architects. In 1999, MBA obtained ISO 9001 quality certification.

Since the ‘80s, he has been increasingly successful in the field of architecture in Europe, Japan, the United States, Australia and the Arab Emirates.

Projects built

• Museum of Islamic Arts at Louvre Museum, Paris, 2005-2012

• Museum of the City of Bologna, Italy, 2004-2012

• Urban redevelopment “Verona Forum”, Verona, Italy, 2004–2011

• Radical refurbishment of the Deutsche Bank in Frankfurt, Germany, 2007–2011

• National Gallery of Victoria extension and redevelopment, Melbourne, Australia, 1996–2003

• Essen International Fair Extension, Germany, 1998–2001

• Natuzzi Americas Headquarters, High Point, North Carolina, USA, 1996–1998

• Arsoa Co./Cosmetics- Headquarters, Yamanashi, Japan, 1996–1998

• New fair district of the Milan Trade Fair, 1987–1997

• Risonare Vivre Club Complex, Kobuchizawa, Japan, 1989–1992

• Tokyo Design Center, Tokyo, Japan, 1988–1992

• Yokohama Business Park, Yokohama, Japan, 1987–1991

• Villa Erba Exhibition and Congress Centre, Cernobbio (Como), 1986–1990

• Thermoelectric power plant of Cassano d’Adda-Office building, 1985–1990

Projects under construction

• Milan Convention Centre (MIC plus), Europe’s largest convention centre, 2008

• Architectural project of a large Scientific-Technological Park at Erzelli Hill, Genoa, Italy, 2005

• Extension and redevelopment of the Pinacoteca di Brera Milan (one of the major Italian Art Gallery), 2009

• New Cultural Centre of Turin, 2001 (to be started)

Among the best architectural creations

• New Museum of the city of Berlin, Germany, 2008

• Sheikh Zayed National Museum International Competition, Abu Dhabi, UAE, 2007

• European Patent Office, L’Aja, Holland, 2004

• Cittanova 2000, Modena, Italy, 2003

• Redevelopment of the City Centre of Tian Jin, China, 2003

• Cassa di Risparmio di Firenze-Bank-New H.Q., Italy, 2003

• New International Trade Fair of Milan – Rho/Pero, Milan, 2002

• Multifunctional Complex “MAB. Zeil Project”, Frankfurt, Germany, 2002

• Stolitza Towers, Moscow, 1996

• Dubai Creek Complex, Dubai, United Arab Emirates, 1994

• Goshikidai Marine Resort, Japan, 1993

 

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 company was founded in 1945 by Giuseppe Brion and engineer Pajetta. Initially called B.P.M. Company and manufacturing electronic components, the business became known as Brionvega in 1960. In the early 1960s, two unusually designed portable television sets, designed by Marco Zanuso and Richard Sapper, were launched by Brionvega by the names "Doney" (1962) and "Algol" (1964).

Brionvega became famous for a number of exceptional designs (algol, doney, ts502, rr126). A few of their designs found their way into the Museum of Modern Art (MoMA), New York.

2007 DONEY CVT set ( V.Cometti) numbered edition, ALGOL CVT set (V.Cometti) numbered edition,
ALPHA LCD CVT set (V.Cometti)

2002 TVC DOGE 32" (M.Bellini)
1992 GLASS CUBE CVT set (M.Bellini) crystal cubic-shaped television
1992 25" and 28" QUADRO CTV set (M.Bellini) forerunners of the flat screens
1990 15" BEST CTV set (M.Bellini) with triangular rear case
1989 11" ALGOL CTV set (M.Zanuso) newly designed
1988 SINTESI CTV set (R.Lucci-P.Orlandini) with the characteristic orientable loudspeakers
1983 26" CORO PANSOUND CTV set (R.Lucci-P.Orlandini)
1980 23" MEMPHIS CTV set (E.Sottsass) limited series
1980 20" LED CTV set (M.Bellini)
1979 26" ALTA FEDELTA' CTV set (M.Bellini) high audio performance technology
1978 15" MONITOR TV Set (M.Bellini) whose packaging will serve as model for the manufacturing of future PC monitors
1978 15" MONITOR TV Set (M.Bellini) whose packaging will serve as model for the manufacturing of future PC monitors
1969 17" VOLANS TV Set (M.Bellini)
1969 BLACK ST 201 TV Set (M.Zanuso-R.Sapper) first small size TV set designed to be a decorative piece
1968 ASTER TV Set (M.Bellini) sculptural, audio devices in the base
1967 12" DONEY TV Set (M.Zanuso-R.Sapper) evolution of the 14" version
1964 19" SIRIUS TV Set (M.Zanuso)
1964 11" ALGOL TV Set (M.Zanuso-R.Sapper) on display at the MoMA in New York.
1962 14" DONEY TV Set (M.Zanuso-R.Sapper)first transistor portable TV set in Europe, awarded with the Compasso d'Oro.
1961 23" ORION TV Set (M.Albini-F.Helg)
1959 23" CRISTALLO TV Set (R.Bonetto)
1954 Television is becoming widespread.
1945 Giuseppe Brion and engineer Pajetta found the B.P.M. company (initially electronic components), which in the 1960's will become Brionvega, specialized in TV sets.

The BRIONVEGA stylish design is well recognized around the world for it's particularity.
The television here in collection The BRIONVEGA VOLANS 17" VR.S1 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.