The AUTOVOX 879 AMERICA is a 23 inches B/W television with VHF and UHF channels selectors.
Was first models series adopting a hybrid chassis with TUBES + semiconductors both germanium and silicium based.
It has a uncommon light lamp fitted ont the top side of the rear side cover (see picture).
ge 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 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 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 saturation 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.
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
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.
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 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 includcd 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.
AUTOVOX SpA HISTORY
Giordano Bruno Verdesi founded in Rome in 1933 the Industry Italian Radio engineering, IRI, for the production of professional apparates, but this had its single development in 1945 with the war reconstruction post.
Previewing a strong development of the motorization, with Carlo Daroda, it comes up the Autovox SpA, with the specialization car radio production.
In 1953 the company is upgraded and constructed on the way Pays wages to Rome, the new plant for the production of television sets, antennas, car radio, transistor radio receivers, beyond a production of radiosondes and professional apparatuses for the aeronautical meteorology.
With the planning of the first car radio in the world, the leggendaria Bikini, in 1942 it begins a long season of successes like with the car radio Piper, the blue line with the first tuning electronic, the Kanguro the first car extractable stereo, mythical the Shuttle and Challenger the first car radio with the frequency synthesis, represents for Autovox, the flag stones in the development of new technologies, beyond to a complete range of television set (in black and white) of great reliability and from the pretty aesthetic.
Successively it realizes first in Europe, a color television set with fully transistorized chassis. (CLICK HERE TO SEE).
(To see the Internal Chassis Just click on Older Post Button on bottom page, that's simple !)