|
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.
|
Decisions, decisions, decisions.
As the title states, color television manufacturers were, in 1965 when this
Electronics magazine article was published, 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
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.
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
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.
Color and Monochrome (B&W) Television
Articles
|
