The DUMONT (EMERSON) 22 TULSA 16 SE is A Compact 22 inches color television with 16 programs and VST search tuning system.
This set was introducing the P.I.L. Videocolor tube with RCA Technology replacing earlier models with 20AX CRT TUBE SERIES....................a P.I.L. Crt tube family which is primarily intended for use in a color tube having a line type color phosphor screen, with or without light absorbing guard bands between the color phosphor lines, and a mask having elongated apertures or slits. However, the gun could be used in the well known dot-type color tube having a screen of substantially circular color phosphor dots and a mask with substantially circular apertures.
An in-line electron gun is one designed to generate or initiate at least two, and preferably three, electron beams in a common plane, for example, by at least two cathodes, and direct those beams along convergent paths in that plane to a point or small area of convergence near the tube screen.In accordance with one aspect of the invention, at least two electron beams are generated along co-planar paths toward the screen of a cathode ray tube, e.g., a shadow mask type color picture tube, and the beams are converged near the screen by asymmetric electric fields established in the paths of two beams by two plate-like grids positioned between the beam generating means and the screen and having corresponding apertures suitably related to the beam paths. The apertures in the first grid (nearest the cathodes) are aligned with the beam paths.
This kind of CRT was featured in various brands such as Nordmende, Blaupunkt, Salora, Dumont, and others except for those which have had their own CRT tube such as PHILIPS, Toshiba......
Many types of station memories are already being sold on the market which can be divided into two main groups: those with automatic and those with manual television channel searching.
The automatic types are fitted with electronic searching circuits which locate television channels automatically when started by the user. This is done by scanning a given band (VHF or UHF, for example) and stopping on the located channel. Data relative to the located channel can then be memorised by the user in a memory circuit and the same channel recalled whenever required by simply pressing a button which recalls the said data from the memory and supplies it to the channel selection circuit.
This type of circuit is also fitted with components which sense, during search, if a television channel has been tuned into and disable automatic searching to prevent television band scanning from continuing. Most of these circuits are fitted with a phase detector which senses the coincidence between the sync signals received and those regenerated in the receiver (in particular, the flyback signal).
Manual station memories, on the other hand, are fitted with controls which, when activated by the user, start a device for scanning a given television band. These controls also stop the said device when required by the user. When the user sees the required channel appear on the screen, the device is stopped to disable search and enable the channel to be memorised in the appropriate circuit.
In these cases, the simplest way of starting and stopping the search is to fit the circuits with a button which, when pressed, supplies a search-start signal and, when released, stops the searching operation. For best tuning, two buttons are usually provided for band scanning in both directions.
The search tuning starts with pressing the key "S" and an apparatus for indicating a tuned frequency of a tuner of a radio or television receiver, said tuner comprising a tank circuit employing a voltage controlled variable capacitance diode as a circuit element, which diode is supplied in a reverse direction with a scanning control voltage from a solid state potential memory device, which control voltage is set as a result of tuning of said tuner, said indicating apparatus comprising a plurality of light emitting diodes arranged in a line, each illuminating the corresponding frequency indicating region out of a plurality of divided frequency indicating regions of a frequency band to be received by said receiver, said regions being arranged in succession to cover said frequency band, and a corresponding plurality of drivers responsive to said control voltage for energizing the corresponding light emitting diode for illuminating the corresponding frequency region to which said tuned frequency pertains. In a preferred embodiment of the invention, the frequency indicating regions to be covered by the adjacent light emitting diodes are adapted to be overlapped in part at the ends thereof, so that the frequency in the overlapped portion in the region is indicated by said two adjacent light emitting diodes.Further the RF bands class are also displayed with leds in similar way.
With this aim in view, the present invention provides a television tuning device comprising a circuit for continuously scanning at least one band of receivable frequencies, manual control means for starting and stopping the said scanning procedure, a terminal for applying a switch signal for switching from a first band-scanning speed to a second band-scanning speed lower than the first, and detection means for detecting the presence of a television channel by comparing the received sync signals with local signals generated in the television receiver, and applying a switch signal to the said terminal for switching from the said first scanning speed to the said second scanning speed in the presence of the said switch signal, so that the band scanning continues at said lower speed until the manual control means produce the stopping scanning procedure.
These sets weren't expensive, they were sold even under the brand name EMERSON which was indeed the manufacturer of it.
The set have had a name called DUMONT THYRISTOR for the Horizontal Beam Deflection and high voltage generating circuits are realized with Thyristors circuits.
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 fabricated in ITALY at Emerson Electronics S.p.A. in Florence (FIRENZE).
Semiconductors are mainly from PHILIPS / RCA / PLESSEY
This model series was the first DUMONT /EMERSON Using the infrared technology for the remote instead of ultrasonic sound as carrier for remote control trasmission.
Very simple to use.
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.
.........................1967-1977 10 YEARS of color engineering, industrial, administrative and political factors all became hopelessly intertwined in the long but eventually unsuccessful attempt to establish a single colour - encoding system for Europe. From 1962-67 the struggle oscillated wildly between the three main systems - the American NTSC, the French SEC AM and the German PAL. There were also many variations within the SECAM and PAL systems, plus some outsiders such as NIIR, FAM, TSC, SEQUIN, LEP, and counter ideas such as the Post Office's pilot -tone reference system for NTSC, suggested by Dr N. W. J. Lewis in 1964. In February 1965 the official European delegation went to the CCIR Study Group XI meetings at Vienna firmly committed to support NTSC - yet before the end of that year it had swung over equally firmly to support PAL. Indeed for much of 1964 and 1965 the only public support in the Europeans for either PAL or SECAM came from a few technical journalists and the small engineering team at ABC, Teddington. At that period the British industry, through BREMA, was solidly behind NTSC. The BBC's then Director of Engineering, Sir Francis McLean, wrote in March 1965 that "the NTSC system is much to be preferred". The PMG made a statement in the House of Commons on February 3, 1965 in favour of NTSC. Yet today almost everyone in British broadcasting circles sincerely believes that the European made the right choice in opting for PAL. Even in the United States, the birthplace of NTSC, one finds a belief that European television benefits from having chosen PAL or SECAM, though clearly many of the original problems in handling and, particularly, in tape recording NTSC have now been largely overcome. Why did it take skilled engineers and administrators so long to come to what, with hindsight, may seem the obvious choice? And why we were still left with all three systems in general use?
in Varese, Italy, Giovanni Borghi builds a factory for 200
employees to manufacture not only ovens and cooktops, but
also an appliance previously unknown in Italy: the refrigerator.
Ignis workers produce appliances for third-party companies
like Fiat, Atlantic, Philco, Emerson and Philips. Borghi builds
the “Villages of Ignis,” with affordable one- and two-family
houses (Borghi Villages), as well as a pool and sports center
in Comerio, Italy, and a hostel vvith recreational facilities for
young workers in Cassinetta, Italy, all intended to promote a
comfortable, healthy lifestyle.
Borghi was aggressive, flamboyant and flashy. And he took care of his stars - famously buying Spanish sprinter Miguel Poblet a Lancia convertible after his Milan San Remo win. On top of his 25 million lire per year salary.
illumination: refrigerators insulated with Polyurethane foam were much more
efficient and capacious than those hand-filled with mineral wood.
His refrigerators Group, Ignis, developed internally this technology and the
related equipment, a suitable alternative to the imported foam dispensers, which
were difficult to get, fix and maintain, stimulating an industrial supply of
similar machines.
Borghi kept control of IGNIS in the family. In the paternalistic Italian industrial model - like Ferrari, Maserati or Campagnolo. He later turned the reins over to his son, who in turn finally sold the company to Dutch conglomerate, Philips.
When Philips decided to get into the major household appliances
market, its procedure was to buy increasing quantities of these goods from the Italian firm, Ignis, then at the height of its prosperity.
Once it became the principal client of the manufacturer, it took over supplying the latter by purchasing 50 percent of its capital. It took over the firm completely in 1972, to the satisfaction of the founder of Ignis, Giovanni Borghi.
The American company in 1991, acquired the whole of the Ignis, which became Italy s.r.l, Whirlpool and Whirlpool Europe later, and since then is a part of the group, which produced household appliances in the Italian plants, still active
BORGHI DIED IN 1975.
Borghi is still remembered in Italia. RAI even aired TV miniseries about his life this past year, "Mister Ignis".
See also
References
External links
- Dumont Experimental Color CRTs at the Early Television Museum
- DuMont television receiver photo at Greater Boston, June 2005 gallery of broadcasting equipment. Also available is Description and index of entire gallery.
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