The PHILCO (FORD) BLACK CRYSTAL 23" is a 23 inches (61cm) B/W television with 4 programs preselection and potentiometric tuning search system.
The set has a front heavy black glass and the chassis is tubes based since it's the same of older models but with keyboard tuning 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.
Moreover, using this arrangement, the only indication--during adjustment--of which channel is selected is by station identification.
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.
The set has a color burst killer button; Colorburst is an analog video, composite video signal generated by a video-signal generator used to keep the chrominance subcarrier synchronized in a color television signal. By synchronizing an oscillator with the colorburst at the back porch (beginning) of each scan line, a television receiver is able to restore the suppressed carrier of the chrominance (color) signals, and in turn decode the color information; to block picture disturbing behaviour during color transmissions.
(Television set kindly donated to me by Marshal Elia Z.)
Here you can see a nice PHILCO Washing Machine.
Philco, the Philadelphia Storage Battery Company (formerly known as the Spencer Company and later the Helios Electric Company), was a pioneer in early battery, radio, and television production as well as former employer of Philo Farnsworth, inventor of cathode ray tube television. It is currently a brand of Philips.
Philco's rise to the top of radio makers was an amazing feat. While other makers like Atwater-Kent, Zenith Electronics, RCA, and many now-forgotten others (Freshman Masterpiece, FADA Radio, AH Grebe, etc.) sold many battery-powered radios in the early 1920s, Philco made only batteries, "socket power" units, and battery chargers. With the invention of the rectifier tube, which allowed radios to be operated from the wall socket, Philco knew their business was doomed, and decided in 1926 to get into the booming radio business. By 1930 they would sell more radios than any other maker and hold that first place position for over 20 years.
Philco built many iconic radios and TV sets, including the classic cathedral-shaped wooden radio of the 1930s (aka the "Baby Grand"), and the very futuristic (in a 1950s sort of way) Predicta series of television receivers.
Philco started experimenting with television in the early 30s and financed for a while the experiments of Philo T. Farnsworth, considered by many as the “father of television.”An experimental TV station was licensed to Philco in 1931, one of the first all-electronic television ;
Granting
of such experimental broadcasts by the FCC was common practice at
that time, as television took its first tentative steps in New York
City, Schenectady, and Philadelphia. While the
rest of the country remained oblivious to the new medium, viewers in
those cities bought several thousand sets to watch the limited
schedule of programs transmitted by pioneering broadcasters of the
East Coast who jumped at the opportunity to go from experimental to
commercial television broadcasting.
By
1937, Philco was using an experimental 441-line television system
which utilized a 12” television receiver—a direct, but bulky
competitor to David Sarnoff’s RCA 12” set.
Along
with the stations that would become WNBC-TV and WCBS-TV in New
York City and WRGB-TV in Schenectady, WPTZ-TV, Philco Corporation's
station in Philadelphia, gravitated to sports to fill air time.
On
October 5, 1940, when there were about 700 sets scattered
throughout the Philadelphia area, Philco broadcast the University of
Pennsylvania's Quakers 51-0 victory over the University of
Maryland at Franklin Field.Today, the Philco brand name is carried by several different companies and holding groups throughout the world.
Philco International
In
1974, 13 years after purchasing the Philco Corporation, Ford
begins divesting part of the Philco business by selling the
Consumer Electronics Division to GTE Sylvania. Three years later,
Philco International is purchased by White Consolidated Industries
(WCI). In 1986, Philco and WCI are purchased by AB Electrolux of
Sweden. And, in 1988, Philco finally moves out of Philadelphia to
Pittsburgh, to join other WCI affiliates.
Itautec-Philco S.A.
In 1989, Philco-Brasil is bought by the group Itaúsa, part of Bank Itaú. Most
of its plants are centered around three plants in Manaus for the
manufacture of TV sets, video cassettes, fax machines, printers,
and PC boards.
It
is owned by Jorge Blanco Villegas and has a plant in Ushuaia, Tierra
del Fuego. It manufactures mostly Semi Knock Down (SKD) type
components, i.e., fabrication of pre-assembled PC boards and
components. The German company VDO imported Philco-Argentina auto
radios into Brazil for a while¾but with little success.
Philco-Italia S.P.A.
During
the 70s, Philco-Italia became part of Bosch-Siemens and was
subsequently acquired in 1987 by the Gruppo Merloni with Felice
Colombo as president. It currently manufactures
refrigerators and air conditioners in northern Italy having
distributors in all 5 continents, Philco G.B. Ltd. in England, Philco
Trading in Egypt, Bendix Unit B1 in Australia, among others.
Some References:
"Archived copy". Archived from the original on 2013-07-10. Retrieved 2014-04-13.AntonioMerloni.it Archived 2006-10-04 at the Wayback Machine
Eschner, Kat. "The Farmboy Who Invented Television". smithsonianmag.com. Retrieved 24 April 2018.
"The Museum of Broadcast Communications - Encyclopedia of Television - Farnsworth, Philo". www.museum.tv. Archived from the original on 30 April 2017. Retrieved 24 April 2018.
Mahon, Morgan E. A Flick of the Switch 1930–1950 (Antiques Electronics Supply, 1990), p.117.
A Brief History of Philco Archived 2005-08-02 at the Wayback Machine Oldradio.com
Internal Philco Corp. document Philco-Ford Image, by Glenn Allison, app. 1965
Mahon, p.116.
Mahon, p.127.
Peck, Merton J. & Scherer, Frederic M. The Weapons Acquisition Process: An Economic Analysis (1962) Harvard Business School p.619
Internal Philco Corp. book The Story Of The Philco Franchise, 1954
MZTV - Museum of Television http://www.mztv.com/newframe.asp?content=http://www.mztv.com/predicta.html Archived 2013-11-20 at the Wayback Machine
Wall Street Journal, "Philco Claims Its New Transistor Outperforms Others Now In Use", December 4th 1953, page4
Saul Rosen (Jun 1991). PHILCO: Some Recollections of the PHILCO TRANSAC S-2000 (Computer Science Technical Reports / Purdue e-Pubs). Purdue University. Archived from the original on 2016-03-04.
https://docs.lib.purdue.edu/cgi/viewcontent.cgi?referer=&httpsredir=1&article=1890&context=cstech. Missing or empty
|title= (help)
"Fifth Generation Computers - Patents and Licensing". www.fifthgen.com. Archived from the original on 4 October 2017. Retrieved 24 April 2018.
Saul Rosen (Jul 1968). Electronic Computers —- A Historical Survey in Print (Computer Science Technical Report). Purdue University Department. Archived from the original on 2016-03-04.
Inventing the Electronic Century, Author: Alfred Dupont Chandler Jr., Page 40
The Philco Serviceman, September 1955, Volume 23 No.9
Wall Street Journal: "Radio Men Told Of Rapid Counter", March 25, 1955
Wall Street Journal, "Chrysler Promises Car Radio With Transistors Instead of Tubes in '56", April 28, 1955, p.1
Hirsh, Rick. "Philco's All-Transistor Mopar Car Radio". Allpar.com. Archived from the original on June 3, 2013. Retrieved June 1, 2013.
"Mopar 914-HR Ch= C-5690HR Car Radio Philco, Philadelphia" (in German). Radiomuseum.org. Archived from the original on October 16, 2013. Retrieved June 1, 2013.
Walter P. Chrysler Museum, "Archived copy". Archived from the original on 2014-01-02. Retrieved 2016-03-18.
Philco TechRep Division Bulletin, May–June 1955, Volume 5 Number 3, page 28
Wall Street Journal; June 28 1955; page 8; "Phonograph Operated On Transistors to Be Sold by Philco Corp."
"TPA-1 M32 R-Player Philco, Philadelphia Stg. Batt. Co.; USA" (in German). Radiomuseum.org. June 28, 1955. Archived from the original on October 21, 2013. Retrieved June 1, 2013.
"The Philco Radio Gallery - 1956". Philcoradio.com. March 12, 2012. Archived from the original on June 21, 2013. Retrieved June 1, 2013.
Digital Computer Newsletter, Office of Naval Research (unclassified), April 1957, pages 7-8
Chicago Tribune, March 23, 1958, "All Transistor Computer Put on Market by Philco", page A11
Rosen, Saul, "Recollections of the Philco Transac S-2000" Archived 2011-06-29 at the Wayback Machine, IEEE Annals of the History of Computing, vol. 26, no. 2, pp. 34-47, Apr.-June 2004.
"Profile: Philco" Archived 2010-09-20 at the Wayback Machine, Computer History Museum
Philco Corporation, "Philco Transac S-2000 Information Brochure" Archived 2010-07-07 at the Wayback Machine, 1958
Gilchrist, Bruce, "Remembering Some Early Computers, 1948-1960" Archived 2012-10-22 at the Wayback Machine, Columbia University EPIC, 2006, pp.7-9. (archived 2006)
Los Angeles Times, June 02, 1959, page 10
Wall Street Journal, October 09, 1957, page 19: "Philco Says It Is Producing A New Kind Of Transistor"
Fortune Magazine, September 1959 issue, page 55
The New York Times, June 01, 1959, pages 37,41
Dethloff, Henry C. (1993). "Chapter 5: Gemini: On Managing Spaceflight". Suddenly Tomorrow Came... A History of the Johnson Space Center. National Aeronautics and Space Administration. p. 85. ISBN 978-1502753588. Archived from the original on 2015-07-20.
"Big Gain Reported In Purifying Water". The Toledo Blade. Associated Press. 1971-09-09. Retrieved 2013-10-24.
Ford Motor Company 1973 Annual Report, page 15
"Company History". Archived from the original on 2014-10-31.
"Archived copy". Archived from the original on 2016-03-04. Retrieved 2014-12-05.
"IG.com.br". ig.com.br. Archived from the original on 20 May 2013. Retrieved 24 April 2018.
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