0004133373@mcimail.com (Donald E. Kimberlin) (02/24/91)
Re: Subject: The Year Was 1960
Continuing a thread that began in Digest V11, issue 123,
Richard Budd commented on color TV in issue 128,
> It's been available since the early 1930's, although before World War
> II it was strictly experimental.
Credits for the first color televison date to a Scot, Charles
Baird, in 1927 experiments to produce color images by mechanical
scanning methods. Baird was expanding on 1880's work that began with
Senlecq's lab work on the photoelectric properties of selenium and
Nipkow's development of image scanning with a perforated rotating
disk. (In fact, there is some history showing facsimile by purely
electric means dates to about 1847.)
The problem of Baird's day was providing a transmission
channel. Bell Laboratories was of course interested, and duplicated
Baird's work, which in recent times has given rise to misleading AT&T
television commercials that imply Bell developed color TV. In 1934,
Philo Farnsworth (independently) and Vladmir Zworykin (at RCA)
developed electronic image scanners. These resulted, combined with
achieving sufficient radio bandwidth, in pioneering television
broadcasts by the British Broadcasting Corporation commencing November
2, 1936, almost three years before American TV began at the 1939 New
York World's Fair.
Broadcast color television was stalled for a number of years
while the Columbia Broadcasting System continued development of
mechanical methods of separating primary colors based on Baird's work,
in competition with RCA's work on extending Zworykin's electronic
method. In their first iterations, both required broadcast channels
far wider than the monochrome transmissions already on the air. The
Federal Communications Commission of the US was unwilling to authorize
use of so much radio spectrum for color television, and ultimately got
the National Television Standards Committee to moderate a system for
broadcast use. The RCA electronic method won out when it proved most
compatible with existing monochrome methods. While both CBS and RCA
method experimental transmissions had been aired, the final NTSC
agreement was issued in 1953, permitting regular color transmissions
to spread across the US after that time.
Budd closed by saying that:
> FM has also been around since the 1930's.
Our Moderator, always the (rightfully) proud Chicagoan, replied:
> The first FM radio station in the US was here in Chicago, started in
> 1941 by the Zenith Radio Corporation.
I have to take some issue there, Patrick. Just like
transmitting pictures, FM has a physics lab history dating to 1862
work of Hermann von Helmholtz, amplified by Lord Rayleigh in England
(a name famous to every radio engineer) in 1883. In 1925, John Carson
at Bell Labs published on the value of using FM to reduce noise in
communications links. It was (retired) Major E. H. Armstrong (to whom
we owe credit for the superheterodyne receiver that made broadcast
radio really a practical medium for the general public) who in 1935
aired the first broadcast FM transmissions in 1935, from a transmitter
atop the Empire State Building to receivers in New Jersey. (Sorry,
Chicago.) Both CBS at New York and Zenith at Chicago were early
promoters of FM broadcasting.
Coincidentally, Major Armstrong put a subcarrier on his 1935
transmitter, demonstrating multiplex transmission of audio programs
with facsimile newspapers. He obtained a patent for FM that resulted
in a bitter battle with AT&T about patent rights; one in which the
classic "phone company stonewalling" often mentioned in the Digest may
have resulted in Major Armstrong's suicidal hurling himself out of a
New York office window. In a very complex argument involving the
means of generating frequency-modulated versus phase-modulated
signals, the Bell interests maintained their microwave transmitters
did not violate Armstrong's patent, denying him of course millions of
dollars in patent rights.
Armstrong's method of generating FM required quite complex
frequency multiplication, then downconversion, then remultiplication
to achieve an output signal in the region below 50 megaHertz, which
was in that era, the only one in which high-powered transmitting
amplifers could be built. (FM radio before WW II was in the region
42-50 mHz.) Leave out the downconverter, and the result wound up at
600 megaHertz or more, a useless part of the radio spectrum in the
mid-1930's. Bell Labs did this, and proceeded to develop means to
focus super high frequency radio waves with reflector antennas that
could work with only a fraction of a Watt of transmitter power,
multiplexing at first 120, then 240 telephone voice channels on a
single radio channel.
Later improvements after WW II extended this to 600, then 1800 voice
channels on a single microwave radio. In more recent developments,
Bell Labs did pioneering work in polarizing antennas so microwave
channels could be placed half as far apart in the radio spectrum, and
most recently, modified the system to single sideband FM, obtaining a
further doubling of the number of microwave radios that can be run
along a given route.
All this history became very personal when I first worked in
radio stations that had on the transmitter plant wall, not only an FCC
license to transmit, but also had a patent license issued by
Armstrong's widow. Later, at AT&T, I questioned photos of TD-2
microwave equipment bays with covers enclosing them. An AT&T manager
I worked with told me how he had seen them used only at New York, in
early days when Major Armstrong would come to inspect with his
lawyers. The AT&T employees were under instruction to keep the doors
closed and not speak to Major Armstrong when he came to inspect the
installation.
I hope this rambling from the mists of telecom history is of
interest and value to readers here. We owe far more to heroes who
labored with balky, complex apparatus than modern histories ever seem
to credit.
[Moderator's Note: Thanks for another excellent article, which all of
us have come to expect from your terminal. But I must question the FM
thing a little. I listened to WEFM for *many* years, and they
frequently discussed this. Of course it was over a dozen years ago the
station changed format and I quit listening. My memory may be a little
hazy. Was the station in New York on the air continuously on a regular
schedule in the 1935 => 1941 period? Zenith's claim was they were the
first on the air with regularly scheduled, commercial programming on
the FM band. Of course, Zenith itself was the one and only sponsor for
the lifetime of the station (as a classical station) for 36 years.
The day the format changed in 1977 was a sad one. Everyone knew it was
coming as Zenith had been trying to sell the station for quite some
time. Metromedia finally agreed to buy the station but without the
classical music format. Through a quirk, the FCC approved the sale,
but did not approve the change in format for another year, so
Metromedia, whose stations are easy listening and top forty rock found
itself stuck with running a classical station for awhile. But when the
change in format was approved, they wasted no time in the conversion.
The FCC required them to give a week's notice to the listeners. A
disclaimer was played hourly for a week advising that the FCC had
given permission to change the format, and " ... for continued
listening to classical music, we suggest you tune to WNIB or WFMT ..."
On the final night, the last selection was Beethoven's Fifth Symphony,
followed by their usual five minutes of news at 11:55 PM. At midnight
they gave their usual sign-off announcement followed by the Naitonal
Anthem, as was their custom. After about fifteen seconds of dead air,
a nasal, obnoxious sounding voice told us we were listening to the
home of top forty rock in Chicago. Their first selection was "Rock
Around the Clock". The FCC made them keep playing the disclaimer once
an hour for another week, then several times daily for a month. PAT]0004133373@mcimail.com (Donald E. Kimberlin) (02/26/91)
In commenting on my original post (Digest v11, iss156), our Moderator wrote: > [Moderator's Note: Thanks for another excellent article, which all of > us have come to expect from your terminal. Golly, thanks, Patrick. You should have seen the rosy blush my little T-1000 laptop emanated when it displayed that line. But please don't do that too much. It got so coy the rest of the day that I spent too much time coaxing it back out so I could tickle its keys some more! More along the thread, our Moderator continued (about Chicago's WEFM having been the *first* FM broadcast station): > ...Was the station in New York on the air continuously on a regular > schedule in the 1935 => 1941 period? Zenith's claim was they were the > first on the air with regularly scheduled, commercial programming on > the FM band. Armstrong's 'station" was purely an experimental one, and Zenith's claim that WEFM was the first regular station was certainly correct. My original remark was taking issue with a broad claim phrased in a way implying that Zenith was the first ever, thus perhaps creating the impression that Zenith was the developer of FM. In radio engineering education, the frist reference is always to Armstrong's 1935 experiments and his landmark paper read to the Institute of Radio Engineers in 1936. In New York, CBS also jumped on the FM bandwagon, but I do not have a date to compare to Zenith's Chicago operation. I do have in my own history book collection a 1942 engineering text that describes FM broadcast trnsmitters made by Armstrong, GE, RCA and Western Electric, all of which operated in the 42-50 mHz range, the original "FM band." On a different vein, our Moderator mentions how the FCC involved itself in the sale of WEFM concerning programming, saying: > ... the FCC approved the sale, but did not approve the change in > format for another year. The FCC required them to give a week's > notice to the listeners. A disclaimer was played hourly for a week > advising that the FCC had given permission to change the format, > and " ... for continued listening to classical music, we suggest you > tune to WNIB or WFMT ..." Ah, yes, the good old, bad old days of close regulation. The WEFM sale must have been the last of the era in which the FCC concerned itself with what kind of programs the public had access to in each market. In that time, each broadcaster had to propose to the FCC how much of each type of programming ... news, sports, education, music (by type), religion, and such it would air, brokne down into commercial and non-commercial amounts. Then, at triennial license renewal time, do an analysis from sample program log dates set by the FCC, showing how well the proposal was complied with, explaining any significant deviation. The "deregulation" of broadcasting preceded that of telecom by quite a few years. Many believe it led to the destruction of radio as an important information medium in America. One last note about the balky apparatus of early FM: My radio "Alma Mater: had one of the Western Electric 10 kilowatt FM trans- mitters, that had as a "feature" a motor-driven automatic frequency control circuit. It worked rather well, except that if there was a sustained low-frequency note, the darned thing would decide one of the large sidebands was the carrier frequency, and crank itself over there. When the note stopped, it lost track of where it should be, and the motor would just run off to one end of its track. The old WECo transmitter's power amplifiers were so broadly tuned, it would wander a full two megaHertz up the band, and park on top of one of the other stations in town, still putting out its full 10 kilowatts. At the same time, our fine Hewlett-Packard frequency monitor had circuitry such that it indicated zero deviation from assigned frequency every 3500 Hertz up the band, so its needle would settle with the appearance that we were just in fine shape. Our "alarm" would be some combination of the studio calling to say we "went off the air," and relaying calls from listeners who said they heard us on top of the other station! That other station had a GE transmitter using different circuitry with its own annoying version of the same habit, but a tendency to go clear off into Lord-knew-where in the radio spectrum. They had a subcarrier with the local Muzak on it, so their "alarm" would be the guy from Muzak calling up to say his customers lost their music. Somehow, life was a lot more adventuresome in those days.... [Moderator's Note: But I don't recall WJJD (1160 AM here) or WLS (890 AM) going through such efforts to change their format. WJJD went from a classical format to Country and Western overnight with no notice at all. And WLS: what a switch that was! It was 1959 or 1960. After years of ownership by Sears, Roebuck (the <W>orld's <L>argest <S>tore, after all!) WLS had become just what their nickname implied: The Prairie Farmer Station. From early in the morning with a farm show and someone discussing the condition of the crops to late at night with the Old Barn Dance program from Nashville, TN, they spent the day with soap operas from the Mutual Network and Country/Western music. The exception was Sunday: From 6 AM until midnight, it was one preacher after another; thirty or sixty minute slots brokered to every crackpot with a post office box in Pasadena, CA. When WLS decided to go with rock music, they brought in several good DJ's, and switched the format at 6 AM one morning while everyone was still asleep. They bought off all the Sunday preachers who still had time left on their contracts and dumped them all the same week ... all but one ... a local guy here in Chicago named Preston Bradley, whose church services had been on WLS for umpteen years. They couldn't buy him off, and he still had two years to go ... so for two years following the change in format from Prairie Farmer / soap opera / peculiar religious stuff to a hard rock format, every Sunday they stopped the music at 10:58 AM and the DJ would say "It's time for Doctor Bradley ... I'm going out for breakfast ... we'll be back at noon." And at exactly noon they would cut him off the air, as often as not in mid-sentence and start the rock music again. I'm sure it pained them no end to have to suspend for an hour. The only time I heard any complaints from the FCC about them was when a DJ (remember, this was early sixties) said a naughty word on the radio one night. The FCC made them go off the air a few minutes later; they got (I think) a three day suspension of their license. PAT]
gah@hood.hood.caltech.edu (Glen Herrmannsfeldt) (02/28/91)
There is a small confusion here related to the term FM. THere is FM, frequency modulation, which can be used at any frequency. There is the FM band, from 88 to 108 MHz, which is what almost everyone calls FM. The modulation method came before the band. Someone did each first. Sorry if this is obvious, but the distinction was not obvious in the previous note.
alan@relay.eu.net (Alan Barclay) (03/03/91)
In article <telecom11.156.1@eecs.nwu.edu> 0004133373@mcimail.com (Donald E. Kimberlin) writes: > Credits for the first color televison date to a Scot, Charles >Baird, in 1927 experiments to produce color images by mechanical >scanning methods. Baird was expanding on 1880's work that began with >Senlecq's lab work on the photoelectric properties of selenium and >Nipkow's development of image scanning with a perforated rotating >disk. (In fact, there is some history showing facsimile by purely >electric means dates to about 1847.) It was actually John Logie Baird, the inventor of television, who also invented colour televison, and it was because he was working on the colour system at the time of the first experiments in broadcast TV that Baird's system was not adopted as the B/W broadcast system.