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December 27, 1965 Electronics
 [Table of Contents]
Wax nostalgic about and learn from the history of early electronics.
See articles from Electronics,
published 1930 - 1988. All copyrights hereby acknowledged.
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Decisions, decisions,
decisions. As the title states, color television manufacturers were, in 1965,
finding themselves between a rock and a hard place, as the saying goes, regarding
a change from vacuum tubes to transistors. The buying public (aka consumers)
had mixed emotions about the newfangled semiconductors based at least partly
on bad information about transistors. Transistors had been designed in various
circuits for a decade and a half and were gaining rapidly in performance and
reliability. The price was coming down, but as reported here, still cost $5
to $10 apiece compared to a $1 vacuum tube. Company management needed to decide
whether to delay implementing the new engineering and production methods required
to deal with transistors for a couple more years until the market had more time
to make up its mind whether to begin. A couple firms enthusiastically adopted
the new technology and was forging ahead with hybrid models that used transistors
wherever they could replace tubes. High voltage and high frequencies were out
of the question, but IF and baseband were easily accommodated. The TV industry
went through the same sort of reluctance when switching from round to rectangular
picture tubes (CRTs). On the not-so-far-off horizon was still the dilemma of
integrated circuits and what role - if any - they would play in television sets.
Anxiety Amid Affluence: Why Color-TV Makers Worry
With demand for their product outstripping plant capacity by 30%, 13 major
companies are rushing into transistorization. Some are doing it reluctantly,
under the pressure of competition
By Louis S. Gomolak
Chicago News Bureau
Admiral Corporation's Leonard Dietch, believes transistors
should be used wherever they are economically possible. Admiral plans to transistorize
everything but the high-voltage deflection circuits. It will also use an integrated
circuit.
Makers of color-television sets are worried. Although demand is 30% ahead
of their ability to produce receivers, they fear technological obsolescence.
With transistors working their way into color tv, and integrated circuits
beginning to appear in design rooms, can the producer afford to stand pat with
his present designs?
Last June, when the Philco Corp. announced plans to build hybrid 19-inch
sets late this year - with 32 semiconductors and 16 vacuum tubes - its competitors'
initial reaction was: "Who needs another technical advance? Changing to a rectangular
picture tube from a round one is enough for one season." But every major producer
put its engineers to work designing solid state circuits for color tv.
And last month, when it was disclosed that the Admiral Corp. - which ranks
third in color-tv sales - plans to use an integrated circuit to demodulate the
color signal in a 15-inch portable, the activity intensified in design rooms
and in executive suites. Even companies that oppose the shift now, on technical
grounds, are among the 13 big concerns that plan to introduce semiconductors
in early models. Many agree with Admiral, which considers transistorization
necessary, beyond technical reasons, to maintain what one official describes
as "the company's image as a progressive force in the consumer market."
I. Reluctant Innovator
At the Zenith Radio Corp., J. E. Brown, vice president for engineering and
research, warns: "Degraded performance, starting with the tuner, is all you'll
get" in changing to transistors. "There isn't a radio-frequency transistor on
the market as free of cross-modulation phenomena as the vacuum tube you want
to get rid of," he declares. Brown concedes that one solution may be the field
effect transistor, a high-impedance device whose characteristics resemble those
of a vacuum tube. But these are not being produced in great enough volume, he
adds.
Yet Zenith is planning to offer hybrid receivers next year. So is Setchell-Carlson,
Inc., despite the fact that its chief engineer, Fred G. Melius, agrees with
Brown's technical objections.
One of the transistor's strongest advocates is Raymond L. Osborn, director
of tuner engineering at the Oak Electronetics Corp., the biggest supplier of
tv tuners. "We've produced over 100,000 transistorized color-tv tuners since
the second quarter of this year," he says, adding, "the noise and gain figures
are competitive with tube tuners."
Oak's vice president for marketing, Paul W. Wheaton, adds that the transistorized
tuners are also competitive in price with tube tuners.
Little by little. Some companies plan to ease into hybrid
design by transistorizing the least demanding spots first - the low-level processing
and control circuits. Theodore S. Zelazo, assistant chief engineer at Muntz
Tv, Inc., thinks the best place to start transistorization is in the sound and
synchronization circuits. C. J. Dumas, a research manager at the Hoffman Products
Corp., thinks reliability would be doubled if all low-level circuits were transistorized.
Both companies are designing 19-inch hy-brids.
But Admiral's manager of color tv engineering, Leonard Dietch, believes transistors
should be used now wherever they are economic-ally possible. Admiral plans to
transistorize everything but the high-voltage deflection circuits. The use of
transistors to this extent, Dietch says, "doubles set reliability, shrinks package
size and cuts power consumption." The company's 19-inch hybrid will consume
160 watts, he says, compared with 265 watts for Admiral's comparable all-tube
set.
All the way. Sylvania Electric Products, Inc. opposes hybridization;
the subsidiary of the General Telephone and Electronics Corp. expects to have
a fully transistorized receiver ready by 1967. W. D. Shuster, engineering manager
in the entertainment products division, says, "It makes more economic and performance
sense than just going half way."
The Wells-Gardner Electronics Corp. and Warwick Electronics Corp. have both
confirmed plans to build hybrid sets, but will not disclose the extent to which
they will use transistors. Warwick sells its receivers under the Sears Roebuck
Corp.'s Silvertone label and Wells-Gardner supplies tv's for the W. T. Grant
Co., the J. C. Penney Co. and the Western Auto Supply Co.
Four manufacturers, all reported to be designing hybrid sets, will not talk
about it. The General Electric Co. is said to be working on both hybrid and
completely solid state versions of its 11-inch Porta Color set. The Radio Corp.
of America, the leading producer of color-tv sets, is reported to be designing
15- and 19-inch hybrids; Motorola, Inc., a 19- and possibly a 21-inch set; and
the Magnavox Co., a 21-inch set.
II. Deflection Circuits?
All the companies interviewed, except GE, agree that transistorization of
the high-voltage deflection circuits is impractical now for technical and economic
reasons.
"There is no single economical device that can handle 25,000 volts," says
Warren C. Letsinger, customer assistance manager at the General Motors Corp.'s
Delco Radio division. "One transistor, the experimental 2N2580 could, but one
of them costs $100." Two Delco DTS 423's in series, which cost about $8 each
at the distributor, could also do the job. But these transistors would be operating
so close to their maximum ratings that their switching times would have to be
perfectly matched.
Delco, along with Texas Instruments Incorporated and Motorola, is working
on a single device to solve the deflection problem. Delco's unit, similar to
its DTS 423, but with a higher rating, is believed to be the farthest advanced.
Despite its reluctance to discuss its plans, GE seems to have solved the
deflection-circuit problem. Peter Humeniuk, engineering manager at the company's
tv-receiver department, says, "Devices are available to transistorize the entire
set, from tuner to deflection stages. The somewhat higher cost is to be expected.
Economics. How much will the consumer be willing to pay
for the more expensive solid state components?
Zelazo, at Muntz, says, "The magic pulling power of the word transistor is
worth a price differential of $30 or more in the market." John H. Schumacher,
head of Warwick's design engineering, says, "Between $15 and $25 retail." Dietch,
of Admiral, Humeniuk of GE, Pierce of Wells-Gardner and Melius of Setchell-Carlson,
generally agree that hybrid sets should only cost 5% to 10% more than present
tube sets do.
Dietch adds that increased component cost for hybrid sets could be somewhat
offset by the labor-saving techniques by which the sets could be fabricated.
Brown, of Zenith, believes that improved styling, resulting from smaller
components, will support higher prices. Brown believes hybrids will cost $50
or $60 extra, but he says the public will pay it. Second generation sets, he
adds, will cost less because of lessons learned while producing the first generation.
Philco is recommending a retail price of approximately $450 for its 19-inch
hybrid tv. The Philco 21-inch all-tube set now sells for about $370.
III. IC's in 3 to 5 Years
Although Admiral is already introducing an integrated circuit into its sets,
most producers don't expect widespread use of IC's for three to five years.
Dumas, of Hoffman, sees "very good possibilities for an IC set by 1968." Brown,
of Zenith, says, "A minimum of three years, but more likely five." Philco sees
1972 as the big year for IC's in color tv. "We estimate six to eight (integrated)
circuits will be used per set," a spokesman says. "By 1972, from 20 million
to 25 million circuits will be needed to meet production needs." He declines
to predict the dollar volume of the requirement because "the same wild pricing
that affected transistors has already engulfed integrated circuits."
Admiral is keeping IC's out of the video strip at present, Dietch says, "because
transistors do the job there and cost less." The company is using an IC in the
color demodulator in its 15-inch hybrid "because the frequency-range requirements
are low, and one IC replaces many tubes or transistors in one shot," he explains.
The IC replaces all the components previously used in the color demodulator,
also two other transistors and their associated circuitry.
Hoffman Electronics may be the next to use IC's. The company believes, according
to Dumas, that "any low-level circuit handling from 20 to 50 volts can be replaced
by IC's now." Dumas says this includes the video i-f amplifiers, color demodulator,
sound circuits, f-m amplifier, synchronization processing and amplifying stages,
vertical integrator and automatic-gain-control (agc) stages.
Posted December 26, 2018
Color and Monochrome (B&W) Television
Articles
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