PHONOLA MOD. 2497/4 YEAR 1968.

The PHONOLA  MOD. 2497/4  A 24 inches B/W television with VHF and UHF channels selectors.
It's one of the last models series from PHONOLA before transition to PHILIPS and it's completely based on Tubes technology.

Was first PHONOLA TV CHASSIS with transistorized tuner units.

The tellye here in collection is AN ORIGINAL FIMI PHONOLA !!

The B/W Tubes Television set was powered with a External Voltage stabiliser unit for Television (portable metal box) which relates to voltage regulators of the type employed to supply alternating current and a constant voltage to a load circuit from a source in which the line voltage varies. Such regulators are frequently provided employing saturable core reactors and condensers connected in circuit...  in such manner as to provide a plurality of variable voltage vectors which vary in different senses, as the line voltage varies, but which add vectorially in such manner that t
voltage stabilization
is automatically effected by the provision of an inductive pilot control device which is adapted to provide two excitation supply voltages for producing excitation or satuation of two magnetic circuits of a reversible booster transformer unit or units and diversion of flux from one magnetic circuit to the other, the booster unit being energized by primary windings from the A. C. supplysystem and being provided with a secondary winding or windings connected between the supply system and the corresponding inain or distribution circuit and in series therewith, through which a corrective boost voltage is
introduced into the circuit under the influence of the pilot control device, of an amount equal to that of the supply voltage fluctuation which initiated it and appropriate in polarity and direction for restoring the voltage to normal value and providing automatic stabilization of the circuit voltage against supply voltages which fluctuate above and below normal value.

Their vector sum remains substantially constant upon variations in line voltage, for providing automatic voltage stabilization of single or multiphase A. C. circuits where the supply voltage and frequency are subject to variation above and below normal value and where the load is subject to variation between normal limits.
The pilot control device which may be employed singly or may comprise three units or their equivalent when applied to multiphase supply systems comprises a pair of closed magnetic circuits or cores constructed of strip wound magnetic material or stacked laminations, the two
circuits forming a pair being constructed of materials possessing dis~similar magnetic characteristics when jointly energized by identical windings in series or by a collective primary winding, the said magnetic circuits being suitably proportioned to provide equal fluxes when energized at normal voltage.

The pilot control device is provided with a main and an auxiliary secondary winding or group of windings, the main secondary winding or windings being adapted to provide a voltage representing the difference in the fluxes of the two circuits to which it is jointly associated, while
the auxiliary secondary winding embraces only one circuit, preferably that subject to the least amount of flux variation. Either of the windings consists of two equal sections or in effect a double winding with a center tapping to which one end of the single winding is connected.

The voltage in the single secondary winding of the pilot device becomes directionally additive to that in one half of the tapped secondary winding and substractive in respect to that in the other half. When the supply voltage is normal the voltage provided by the single secondary winding is zero, since there is no difference of flux in the two magnetic circuits, and the two excitation voltages
produced in the halves of the other secondary winding are equal and when connected to the two excitation windings of the booster units, do not produce any diversion of flux between the two circuits or sets of circuits in the magnetic system of the booster transformer unit become equal, and since the series winding on the booster unit is arranged to provide a voltage due to the difference of
the fluxes in its two magnetic circuits or sets of magnetic circuits, no corrective voltage is introduced into the main circuit by the booster. If, however, the supply voltage varies from normal the pilot control device provides a voltage across the one secondary winding due to the difference in the fluxes of the two dis-similar magnetic circuits of which it is comprised, which voltage is combined with thosc in the halves of the other secondary winding to provide two excitation voltages which vary complementarily to each other as the supply voltage fluotuates, and cause a transference of flux between the two
circuits or groups of circuits in the booster unit and automatically provide a corrective boost voltage in the main circuit in which the series winding of the booster transformer is included of a value equal to that of the variation in supply voltage which initiated it.
The pilot device may be arranged in various ways, forboth single phase and multiphase operation, as exemplified by the constructions hereinafter more fully described.Similarly, numerous arrangements of the booster transformer unit are possible, some of which are hereinafter described in detail. The booster transformer unit embodies thc principles of the inductive devices described in my co-pending Application No. 411,189, filed February 18, 1954.

As an alternative to the provision of an auxiliary secondary winding on the pilot control device this may be
replaced by an independent or external source of supply,which may be either subject to or independent of supply voltage variation, provided such supply may be arranged with a center tapping if required.

Feed-back arrangements may be employed for providing compensation against voltage drop due to the effects of load in various ways. These are preferably providedon the booster transformer unit and may comprise a current transformer in one or more lines of the main circuit,
the secondary output of the transformer being rectified and arranged to energize an additional excitation winding on the booster transformer unit which in clfect increases the amount of the corrective boost voltage as the load increases.

Phonola - Società Anonima FIMI (Fabbrica Italiana Materiali Isolanti); Saronno - Milano
was an Italian manufacturer of radio and television.

Founded in 1929 as Phonola - Società Anonima FIMI (Fabbrica Italiana Materiali Isolanti); Saronno - Milano begun his activity which stopped due to 2nd WOLD WAR.

In 1945 they reprise the production of radio and Television.

in 1969 Phonola was acquired by Philips, later Phonola models are Philips clones
Actual company name and adress:
FIMI SRL, Via Saul Banfi 1, I-21047 Saronno (VA).
FIMI is a company of 'Royal Philips Electronics' and is a global leader in medical display solutions. Its products address a wide spectrum of medical applications ranging from Patient Monitoring to Medical Imaging (such as Ultrasound, Radiography, Magnetic Resonance, Computed Tomography, Surgery ) and to mobile Point of Care.

In the 90's was aquired from the group of Seleco and toghether they went to another Industry group called Formenti.

All these went to failing (Obviously) and they were aquired from SUPER/FLUO in 2006 which even failed in 2009, was dropped to a new society called SELEK TECHNOLOGY founded in 2010.
(Italians awesomeness is well known in the world for these round circles)

Notes:

 Liliana Dal Toso, Vivere Pier Giacomo, in Pier Giacomo 100 volte Castiglioni, Edibus, 2013, pp. 85 e ss.; Matteo Vercelloni, Achille e Pier Giacomo Cadtiglioni, IlSole24ore, 2011, p. 40; Gio Ponti Domus: architettura, arredamento, arte, Edizioni 831-832, Pag. 106. ^ "Ex Seleco a un imprenditore udinese", Articolo del Messaggero Veneto del 18 febbraio 2010 ^ http://www.paginegialle.it/saronno-va/elettrodomestici/fimi ^ Barco acquisisce FIMI, azienda specializzata in display medicali. Un'acquisizione strategica che rafforza la posizione leader di Barco nel settore del Medical Imaging | Barco