The ADMIRAL MOD. IMPERIAL 21" is a 21 inches (50cm) B/w television set.
Tuning is only VHF channels with drum selectors, and an add after UHF Tuner is also present with the knob rear side (badly) fitted.
This is one of the last models fabricated by ADMIRAL before closing the Italian factory ( Admiral Italiana Spa; Milano ) in 1963 .
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. Conventional AC-operated television receivers exhibit several undesirable performance attributes. For example, under low-line voltage conditions such as those encountered during peak load periods or temporary power brown-outs imposed during times of power shortage, picture shrinkage and defocusing are encountered and under extreme brown-out conditions the receiver loses synchronization with a resultant total loss of picture intelligibility.
On the other hand, abnormally high-line voltage conditions are sometimes encountered, and this can lead to excessive high voltage and X-ray generation. In addition, either abnormally high steady state line voltage conditions or high voltage transients such as those encountered during electrical storms or during power line switching operations may subject the active devices and other components of the receiver to over-voltage stresses which can lead to excessive component failure.
It is a principal object of the present invention to provide a new and improved AC-operated television receiver having greatly improved performance characteristics in the presence of fluctuating power supply voltages.
A more specific object of the invention is to provide an AC-operated television receiver affording substantially undegraded performance under even extremely low-line voltage conditions without excessive high voltage and X-ray generation under even extremely high-line voltage conditions.
Still another and extremely important object of the invention is to provide a new and improved AC-operated television receiver having greatly improved reliability against component failure. 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 the
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.
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 a nd 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.
Admiral (brand) Continental Radio & Television Co. (USA)
Continental Radio & TV
Brand: Globe Trotter ; Marshall ; Oriole ; Radiomaster ; Slagle ; Sunbeam ; Wondertone.
Continental Radio & Television Co. with its brand Admiral was one of the big radio producers in the USA and ranked 1939 number 5 in sales volume. Before it was "Transformer Corp. of America" which sold Admiral radios. See below. The end was in 1979.
Admiral is the brand of Continental Radio & Television Corporation, 3800W. Cortland Street, Chicago, Illinois, USA bzw. Admiral Corporation at the same address is the marketing company for the maker.
Ross Siragusa founded the Admiral Corp. during the Depression and transformed it from a small radio and phonograph company into one of the leading makers of televisions, audio products and home appliances.
In 1924, Siragusa had developed an earlier company, Transformer Corp. of America, which grew quickly by selling battery chargers for radios. But by 1929, the Depression caused Siragusa's company to go out of business. Undaunted, he turned to manufacturing radios. To get some start-up cash, Siragusa sold his automobile and home furnishings, and in 1934, created a new company, the Continental Radio and Television Corp., which is known most for its brand Admiral. Growth exploded with the arrival of contracts for military electronics during World War II; afterward, Siragusa steered Admiral into television.
A pioneering TV brand, it became one of the top three in sales and was one of the first to produce color sets. In 1951, Admiral sold five million television sets, but then came a downturn. Disputes simmered over the regulatory framework for color television, and a new excise tax left manufacturers with huge inventories.
By discounting its television sets and increasing its promotion of home appliances, Admiral survived for a while. But during an industry shakeout, with profits falling, the company was sold to Rockwell International Corp., which later pulled it out of the TV business.
The story goes: "A group of four investors founded Continental Radio & Television Corporation in 1934 by literally selling their belongigns to raise the initial capital. The company was a success right from the start. Concentration was on quality to an inexpensive prize. In 1939 Admiral ranked number 5 in sales volume by 1939." [Bunis]. Below we have a bit a different story - and there are early Admiral models ...
Admiral was also successful when the movement of major sales outlets, such as Montgomery Ward and Sears, made their way into the radio sles in the end of the 30s. Continental Radio and Television Corp. made the Admiral, Globe Trotter, Radiomaster and Star Raider brands for them and some more.
Admiral radios were also exported. A catalogue in France [602-39] even lists some French models (5D33X and 952 from the 50s) but they are made in the USA. In Switzerland "Thali" published schematics for the most imported models and Admiral is one of the listed brands from the USA.
Because of quality problems and the growing competition from Japan the plants of the company had to be closed in 1979. The main losses resulted from TV sets.