Who Invented Cable TV?
The purpose of this narrative is to present the historical evidence allowing
you to decide who, if anyone, actually 'invented' cable TV. We begin by defining some terms:
in-vent\in'vent, verb. 1: to think up. 2: to create or produce for the first time. in-ven-tor \-ventar\n.
― Merriam-Webster American origin 'pocket dictionary' (1974).
in-vent/in-vent, verb, transitive. 1: to make, design, or produce something new for the first time: "Alexander Bell invented the telephone in 1876." 2: to think of an idea, story etc., that is not true, usually in order to deceive people: "They invented a very convincing alibi."
― Longman Dictionary of Contemporary English. Essex, UK (2001).
Both anchor invent to first which each agrees means "before (anything
or) anyone else." That seems clear enough for our purpose.
The early history of "cable" (that is the key word here — remember it!)
"TV" is clouded in dissension. Some say it was "invented" in Oregon
(1948), some say Pennsylvania (also 1948 but prior to Oregon). Still others say it was invented even before that — as early as 1937 — in the UK. Let us attempt to settle the issue once and forever. There will be those who, after reading this narrative, will disagree — that's life. But what follows is as accurate as historical references make possible. Indeed, "television by wire" can be dated as far back as 1927, but no participant of that era remains to give us a first-hand report.
First we need to define the key word "cable". You might think that "cable" (as in "cable TV") meant coaxial cable. Think again. Our British cousins used the word "cable" to mean "wire". The two terms were often used interchangeably in the British history of "cable TV." There's a reason for this: coaxial cable was so new in 1936 that it was not yet readily available.
So if you run across a reference to "cable TV" from a UK source, remember this: they are talking about using wires to connect a headend (point of origin receiving station) to a TV set. Two wires may have been twisted together (a "twisted pair"), although the "twisted" part may not have fit the actual installation.
The Alexandra Palace transmitting station in North London is one of the oldest television transmission sites in the world. From 1936 until the outbreak of World War II, it transmitted the BBC television signal at 45.00 MHz visual and 41.50 MHz aural.
During the war, it was used to transmit signals intended to defeat the German Y-Gerät radio navigation system during the Battle of Britain ("Battle of the Beams").
After the war, the transmitter was again used for BBC television until 1956, when it was superseded by the opening of the BBC's new main transmitting station for the London area at Crystal Palace.
In 1982 Alexandra Palace became an active transmitting station again, with the opening of a relay transmitter to provide UHF television service to parts of North London poorly covered by the Crystal Palace Transmitter.
Radio Times, October 25, 1936
The popular British weekly Radio Times published radio and television program schedules. The October 25, 1936 issue included extensive reporting about television, and featured the Alexandra Palace transmission mast on the cover.
As for the TV set, that term wasn't factually accurate either. The TV sets of the day were designed to receive the only available off-air signal — the British Broadcasting Corporation (BBC). The BBC's London transmitter, located at Alexandra Palace (see sidebar), operated on a 45.00-megacycle (what we now call megahertz) visual carrier and a 41.50 mc aural carrier. Transmissions from Alexandra Palace had begun in 1936, but had ceased in 1939 at the outbreak of World War II. At the time of the shutdown, there were between 19,000 and 23,000 receiving sets in service. (Swift, 1950)
When the war finally ended and BBC transmissions resumed, in June 1946, there was a big pent-up demand for new TV sets. But satisfying this demand was problematic for three reasons:
As a starting point for our discussion of the third reason, consider the problem of providing service in apartment buildings. In some London neighborhoods — particularly the more affluent neighborhoods — many residents lived in apartment buildings, some as large as 100 or more dwelling units. These residents were financially able to afford new TV sets. But they couldn't conveniently make a direct connection to an outdoor antenna.
- At the time, off-air reception was limited to London, and later (December 1949) in the Birmingham/Midlands area after a second transmitter began operating at Sutton Coldfield. Given the receiver and receiving antenna technology of the era, TV reception was 'spotty' if at all.
- The post-war UK standard of living into the 1950s was — in comparison with the USA — dismal. A man who earned US$50 weekly in Cincinnati was well paid when compared to his British cousin in Brighton who might — possibly — earn US$20 a week. Even putting food on the table and paying rent was a struggle. Any worker who didn't already own one of the pre-war sets was faced with a $20 US weekly wage against a US$200 fee for a new TV set. Working ten weeks to buy one of the 7- or 9-inch post-war sets simply did not compute.
- The third reason is related to the British definition of "cable". As we noted above, the Brits used the word "cable" to identify wire — bare or insulated, but in any case, unshielded, wire. This stuff worked well enough for citizens who could connect an antenna directly to a TV set. But, as we explain below, it didn't work for citizens who, for one reason or another, couldn't make a direct connection.
To meet the demand of the apartment residents, some entrepreneurs began experimenting with methods for distributing the signal by cable (i.e., wires) to mutliple receivers. Early attempts utilized one of two technological schemes:
- One scheme used two pairs of wires to carry two demodulated baseband signals, video on one pair and audio on the other. Some installations managed to do this with just one wire pair.
- Another scheme also used two pairs. One pair carried a visual carrier modulated at an IF (intermediate frequency) of 9.72 megacycles, suppressed lower sideband (carrier and upper sideband only). The other pair carried baseband audio. This scheme was used in the UK by Rediffusion Ltd, where it was known as the TDUK-1 system. We'll discuss this system in more detail below.
Now stop now and think about that. Why not just distribute the 41.5/45 signal received off the air?
As it happens, Rediffusion Ltd. and others tried to do just that in 1947-1950. It proved "difficult" — in other words, it didn't work.
But we are way ahead of the start here and we will return.
Television through wire?
That is what the British were experimenting
with as early as 1937, perhaps slightly sooner (the exact date is not certain because it
was an experiment to determine how practical it might be). But were they
first to attempt it and — more important — by "wire"?
This gets us to "television" itself. Actually it gets us back before
television; 1906 to be exact. Electron tubes ('valves' in the British
vernacular) were invented late that year by a man who lived the good life but
ultimately died financially embarrassed and way short of his potential; that
would be (Dr.) Lee De Forest and his invention would be called the
It was also in 1906, Christmas eve, in a small radio transmitting shack located
near Plymouth, Massachusetts, where a man had a bold experiment in mind. Virtually all of the
radio transmitters of that era involved a system we knew as spark gap — a technology similar to the way a 1950s-era automobile distributor switched electrical impulses to the 6 or 8 spark plugs, causing them to fire in timed sequence. Inside that black plastic housing was the 50's equivalent
of a 'spark gap' transmitter — much lower in power than the radio transmitters of
1906, but essentially the same technology. Think 'ignition interference' to
radio and TV reception from passing vehicles.
But spark gaps were messy to the radio environment, occupying a bandwidth
many times larger than actually required for code. There had to be a better way
to create radio energy, and one that proved promising was known as the 'high
frequency alternator' ('synchronous rotary spark').
So here is this chap, Reginald Fessenden, sitting there on Christmas
Eve, operating a CW (Morse of Continental) code transmitter, and he does something
nobody has ever done before; he modulates the transmitter with a
voice (his own) and wonder of wonders, 'music' (from a wind-up gramophone
cylinder recorded player ― this is a generation before 'Victrola' and 'laminated
records'). That was possible only because Fessenden had pushed, pulled and
cajoled General Electric to build him (from no prior experience) what would turn
out to be the first modulation-capable device in the world. Previous
attempts (all failures) to 'modulate' a true spark-gap transmitter were disasters;
Fessenden's alternator design would be a major stepping stone to improved code
networks and a way station towards the appearance of 'real' modulation-capable
transmitters — those using De Forest foundation vacuum tubes.
Now imagine you are on a ship at sea and have for whatever reason elected to
tune in the particular code transmissions from Fessenden's experimental station
and there, in your very early vintage carbon-element earphone (typically a
single ear device at the time) you are shocked to hear first a human
voice (Fessenden) and then if you are still conscious and breathing music! This was the first, ever, historically-recorded transmission of anything other than code through a 'radio'
transmitter (Douglas 1989).
Fessenden, you might expect, would have instantly become a 'household word';
the Lindbergh of radio. Wrong. This was long before Fox News and what he did,
as advanced as it may have been for 1906, drifted off into the ether not to be
recalled by anyone of importance for more than a decade. And by then (1919-1920)
the rules of the technology had all changed.
And this gets us to 'wired television' how? We are heading there.
The history of television prior to 1935-1936 is beyond the scope of this narrative save for the 'wired television' subject (but see this article).
In 1927, a year when Secretary of Commerce Herbert Hoover (who would serve as U.S. President from 1929-33), backed the creation of the Federal Radio Commission (predecessor of today's FCC), "television" was in diapers. Television did exist, mostly in the hands of wild-eyed inventor types (Charles Jenkins was one) but in
the best case the number of horizontal scanning lines was only 50, and often even fewer: 16 or 30. Compare that with the NTSC standard of 525 lines used in Canada, the United States, and numerous other counties prior to the digital television transition.
So in 1927 (the 7th of April to be historically precise) AT&T
(yes — that AT&T) demonstrated to the amazement of everyone who could
spell 'television' their ability to send ('transmit') via 'wire' from New York
City to Washington a 50-definition-line image of something nobody remembers
precisely. There are dozens of versions of what the image was — and even some
trade press photos — but it is unimportant to this analysis whether it was
someone's face or a carrot. The 50 lines were conveyed at 16 frames per second
and occupied a total bandwidth of 22 kilocycles.
And this matters why? Well, in the British definition of "cable," this
public demonstration represents the first use of cable to carry television signals over a substantial distance. Not what you might expect from the
history of "cable television"? Of course not, but it illustrates the
point that British origins for "cable television" (in the 1930-40s) and
what we generally define today were in fact two different technologies, related but significantly different. How?
Sending 'video images' through a length of "cable" that extended some
distance (certainly beyond the immediate surrounds of the imaging device —
which by the way was not a 'television camera' as we envision it today)
'connected' to one or more consecutively-joined independent lengths of
additional "wire" that extended from Point A (in the AT&T case, New York
City) to Point B (Washington, DC) was not 'cabled television'.
Not yet, not in 1927. Cable, in our context, 'coaxial', was first announced to
the public in 1929 and it would be 1936 before it actually existed between two A
and B points: NYC and Philadelphia (which in fact would be the first two
'distant points' 'coaxially' connected).
So we can credit AT&T (specifically, Bell Labs) for having been the first to demonstrate that coaxial cable can be used to carry television programming over substantial distances. But AT&T did not invent coaxial cable — that honor belongs to Oliver Heaviside. As this is not a history of Bell Labs, we will leave it at that.
Now let's look at British "cable delivered television." And to
keep the record straight, from this point onward whenever discussing early British efforts, we will mean wired television until that point in time (1947) when
they actually attempted coaxial cable. The attempt failed.
But first, a brief jump to 1948 when the American squabble over "who was first?" began to resonate.
cable tele-vi-sion. also cable TV. noun. a system of broadcasting
television programmes by cable.
cable. noun. 1: a plastic or rubber tube containing
wires that carry telephone messages, electronic signals etc. 2: a thick strong
metal rope used on ships, to support bridges etc. 3: cable television: a cable
channel, 4: telegram.
—Dictionary of Contemporary English (2001); a British origin reference.
cable. noun. 1: a very strong rope, wire or chain. 2: cablegram. 3: a bundle of insulated wires for carrying electric current. 4: cable TV: community antenna television.
| —Merriam-Webster Dictionary (1974); an American origin reference.|
The British approach becomes more fascinating when we consider our more pressing word:
coax. verb. 1: to persuade someone (through multiple examples)|
coaxial does not appear at all.
― Longman Dictionary of Contemporary English. Essex, UK (2001). |
But the 1974 American College dictionary:
co-ax-i-al. adj. 1: having coincident axes. 2: being an electrical cable that consists of a tube of conducting material surrounding a
| —American College Dictionary. Random House, 1974.
This should get us started and we are still ever so briefly in 1948.
- Our Astoria, Oregon claimant (starting Thanksgiving Day, 1948 because that
was the first day that 'his' TV station source — KRSC Seattle — broadcast programs)
installed his system using war-surplus 50-ohm coaxial cable. He charged money to
connect customers but initially did not charge a monthly ('maintenance') fee.
- Our Mahanoy City, Pennsylvania first-ever claimant insisted he was
connecting homes to his master antenna by (or before) June 1948. Alas, he did not
originally use any type of "electrical cable consisting of a tube of
conducting material surrounding a central conductor" — rather he used a form of twinlead. He did not upgrade to true coaxial cable until 1949 or later (the actual year remains one of those unknowns here and it may have been after 1950).
Both of these claimants meet the Merriam-Webster (1974
edition) singular definition of "cable TV": community antenna television.
But the one who did use "cable" (Astoria) collected only a connection fee
initially while the one who collected a monthly fee (by 1949 possibly and
perhaps 1950 or even 1951; Mahanoy City) did not use "cable" by either the
British or American dictionary definition(s) and may not have charged either a
connection or monthly fee for the first year or so of operation (we will explain
So was either first at "inventing" cable TV? Are we looking
for the individual(s) who created the first cable TV 'technology',
or, is this a search for the one(s) creating the 'cable TV business plan'? And were there others, until now unrecognized? We will return
The British 'wired' approach
Before there was television "in the air," there was radio broadcasting. Westinghouse Electric's AM radio station KDKA, Pittsburgh, under the guidance of Assistant Chief Engineer (and amateur radio operator) Frank Conrad, led the way, broadcasting the results of the Harding-Cox Presidential election returns on November 2, 1920 (IEEE, 1994).
From that beginning, when the only listeners were experimenters and (by then) newly-licensed 'hams' using primitive receiving sets, the American radio broadcasting industries would mushroom into one of — if not the — driver to the growth of a post-WWI economy.
By late 1927, our reference year when AT&T transmitted the first crude
images over a wired distance, more than 730 radio stations had begun
broadcasting following the 1920 election broadcast. Americans responded by
purchasing more than eleven million home receiving sets from long-forgotten brand
names such as McMurdo Silver, Scott Transformer Co. and Midwest Radio Corp.
The KDKA election broadcast example exported almost with the speed of light. The UK
took a different approach to the process: government would own (and operate)
all broadcasting stations. There was to be no commercial advertising, even though a few limited 'sponsored programmes' were trialed ― for example, in 1922,
Guglielmo Marconi transmitted entertainment broadcasts from the Marconi Research Centre at Writtle. Following a period of inaugural test operations, 'listeners-in' would be charged an annual fee payable to government. Think of it as subscription radio.
By 1929, there were 2.9 million licensed users in the UK. And, at least in theory, these annual fees (intermittently augmented by receiver point-of-sale government royalty fees as
well) paid the cost of creating and transmitting the programming. This was the
original BBC — the British Broadcasting Company — initially under the
supervision of the General Post Office (GPO). In 1926, it became the British Broadcasting Corporation, still under GPO control.
There were flaws in the plan of course. Listeners could acquire commercially-available ready-built 'receptors' (receiving sets), each of which included a full set of details on the new set owner, thereby allowing records to
be maintained and individuals invoiced annually for the 'listener's tax'. Or,
the price of the receptor might be 'plus annual fee' and collected by the set
retailer, along with the recorded information to be forwarded to the Post Office
What this missed of course would be those who had the patience and skill to build their own radio sets. This was, after all, the era of 'cat-whisker' detectors and inductors wound around
oatmeal boxes — no tubes and no power required!
As more sensitive sets (using vacuum tubes) matured to detect and amplify signals, detailed do-it-yourself instructions appeared in numerous publications. The introduction of speakers allowed the radio sound to blanket a room, thus
eliminating one or more individually-worn carbon-based headsets.
The incentive for do-it-yourself radios was double-barreled: for a quarter or less than the cost of a commercially-supplied receiver in a wooden case you would have a radio. They
called it 'bread boarding' because all of the parts required were suspended
from, and screwed down to, a piece of non-conducting wood about the physical size
of a household breadboard. In fact, actual breadboards were often used.
The second barrel? No registration? No annual license fee!
The General Post Office quickly figured that out. Mail delivery was by postal
employee, door to door. He (they were seldom 'she' in the 1920s) was to do a
daily scrutiny on his route, and as the delivery chap basically knew in person
every individual home's occupants on the route, well, it didn't take long to
determine who had a 'radio set' and who didn't. The postal people were turned into
Radio police notwithstanding, by 1931 the BBC had 3.4 million 'registered' homes paying for
All this leads us to wired radio (a new term) — a place we need to go on our travels to creating cable television. Early on (1924), BBC, for a number of technical and political reasons, was experimenting with what we today call the 'long wave' bands — frequencies below 500 kilocycles, down where today you find aeronautical beacons and almost-sub-sonic Pentagon-to-submarine transmissions.
But most of the world was developing the 'medium wave' range (550 to 1500 kilocycles), following the American lead, and, as the following chart shows, Marconi did the same for his station 2MT, operating at 750 KHz after a brief attempt to use 428 KHz.
The BBC chose the medium-wave band for one of its early experimental station 2LO (either 813 or 857 KHz, depending on the source), but subsequently chose the long-wave band for additional transmitters.
Radio Frequency Bands, as defined in terms of wavelength, the with corresponding frequencies indicated above the chart. Most of European countries, as well as the United States, chose the medium-wave band for radio transmissions.
The British quite correctly imagined that radio would become a powerful propaganda tool and one way to limit the incursion into Great Britain from foreign voices would be to adopt a broadcast frequency range different from frequencies used by other European countries; i.e., below 500 kilocycles. The cleverness of this plan evaporated when several European countries made similar decisions. But even today there remain powerful Marconi-era radio services below 500 kc.
Decades later the French would try a similar trick: they adopted a unique television line standard (819 lines versus the UK's 625) and frequency assignments that made it unlikely that French viewers would be tuning in to TV from neighboring countries — notably Holland.
The BBC was short on funds and slower on the take-up. They began with a London transmitter and then over the years (decades) added supplemental transmitters, just as they would with television although much later — in the '50s. By emphasizing the long wave frequency segment, three things happened, none in their favor:
- Static. Really serious static from nature itself: thunderstorms a half planet away would 'whistle' in on top of transmissions.
- Receiver sensitivity. Well, yes: 200 kilocycles is equal to a wavelength of 1500 meters, or about 4921 feet. A 10-foot piece of wire as an antenna was essentially useless. Grounding the antenna connection to a metal water pipe actually worked better in many cases.
- Interference. England was rapidly changing from a back-garden self-fed economy to major-scale industrial manufacturing. By the millions, country folk were moving into tenement housing surrounding the major cities — that's where the jobs were. Unfortunately, many of those new, modern, pieces of industrial equipment were actually RF generators in disguise, cranking out kilowatts of noise and garbage throughout the radio spectrum, but often most severely in the long wave region below 500 kc. When the local area interference background level exceeded the BBC coverage level, well....
So if Mr. Average Citizen wanted to have a radio for his family (socially,  not having one was like being ostracized and left out, not to mention his total inability to enjoy a pint with his mates at the corner pub where last night's radio programming was the topic of the evening). Alas, inside his tenement, radio reception stunk. There was no back garden area for a suitable antenna, and between the three problems cited above and his nearby neighbors — well, radio did not work.
Furthermore, radio sets were by comparison not inexpensive: in 1928 a radio consisting of a crystal detector and two valves cost more than £2 sterling including the 10% royalty that went to government. Sellers quickly worked out that people who did not have the required number of pounds/shillings/pence for an actual radio set were more likely to have the required number of pence to rent a set. This is not to be confused with time payment purchasing — this was 'you rent it, forever' — or at least for as long as you can make weekly or monthly in-person payments to the local radio shoppe.
This led to "wired radio", or what the British called it at the time: 'piped radio'.
If a radio set in a tenement/row block would not work because of the interference and other reasons previously stated, suppose somebody found a location reasonably close to the tenements where the interference was less obtrusive, and a proper antenna could be installed? If your head is starting to think 'community antenna television' you are on the right track — just two decades in advance.
Wired radio operators were folks/firms who did just this. They found a suitable reception location, and ran 'wires' from that location, nailing them to building fronts, trees, hanging them from lamp posts to provide service to the tenements and rows of terrace houses. But there is more.
You might suspect they received (say for discussion) 200 kilocycles at their quiet location and then sent it by 'wire' at 200 kilocycles to where the potential customers lived, just as community TV antennas would be doing two decades hence. Wrong. That 'wire' would have been a 'super antenna' and by the time it reached the tenements, all of the interference problems would have been magnified umpteen dB over. So they demodulated the 200 kc RF signal, and sent the baseband audio down the wire. Each tenement was in effect an 'additional speaker' to one audio receiver. Most additional speakers were equipped with an 'on-off' switch and a rudimentary volume control/level switch using passive attenuators.
For a price of course. Even then, running wire was not a cheap activity (although the records show some amazing ingenuity attempted — we will explain).
The customers were "subscribers" to a 'master radio antenna/receiver' and, for fewer pence per month than they could rent a full receiver, they received reasonably better BBC reception than they could expect even with a receiver.
Furthermore, there were other benefits: no batteries to replace and no electricity consumed by a radio set. As late as 1950, more than a third of British row houses/tenements were not connected to electricity. They were dependent on a gas pipeline to fuel things that lit up or heated food. Any radio receiver in such a row house would have to be operated by batteries — expensive replaceable batteries.
The largest of these 'radio-by-wire' systems served upwards of 16,000 paying subscribers. And that was in 1947; subscriber counts continued to grow well into the 1950s.
The first recorded installations were in late 1927 (first, there had to be reasonably priced speakers, which did not exist in quantity prior to 1926). By October 1945 there were more than 200 companies (not systems). Some of these companies had dozens of individual
If somewhere in your past reading you have encountered the name Rediffusion and thought to yourself 'this must have been a one-off business', well think again. Rediffusion was one of many wired-radio companies, and ultimately (by 1950) they would, by contract, purchase, or
political will have become the largest piped radio firm in the UK. Today, we'd call them a 'MSO'.
Rediffusion also exported their technology to places like Barbados, Hong Kong, Singapore and even Montreal, where they installed a badly-conceived "wired TV" system in the early 50s. At its peak, Rediffusion claimed systems or partnerships in 75 countries, more than any United States CATV company ever claimed.
What follows may remind you of the very first CATV systems in America in the
early 1950s. Per-subscriber wired-radio income was low (think in terms of 30 US
cents a month in 1930 dollars) and to get to any individual tenement required
wire and, perhaps (not always) insulators. Once inside the residence/flat,
connections were made by 'tapping' into the 'trunk' line. Note that 'tap', in this context, is a CATV term, not to be confused with the actual level of their technology in use — there were no taps. The tech would just wind a 'drop line' around a passing 'trunk line' and hope that there would be sound in the speaker the wired radio company provided.
It was very basic, very rudimentary. Some of the better engineered systems
actually installed audio amplifiers (think trunk line stations in the 60s-70s)
to raise the line levels. Others sent 110V 'balanced lines' (which was half the
voltage of the UK 220V AC mains) down the wire — that same nearly-bare wire nailed to trees and house fronts. That may make you shudder, but there is no apparent reference source for deaths-associated-with-wired-radio-systems.
Some less technically competent companies ran a single wire and drove a stake into the ground at the 'headend' to connect to 'earth' for the second side of the circuit (with more
stakes at subscriber locations). Yes, that was an error, but they still did it
and put up with the 'AC hum' at subscriber locations until somebody tangled with
a hot line and ended up on the front pages of a London tabloid.
And there was competition. An operator who insisted he could not afford 'two
wires' (and whose subscribers endured erratic AC hum in their speakers) often found a competitor 'over-wiring' their 'plant' with two (or even more) wire systems.
And this could be a point to remind you that in British English, the definition of 'cable' includes the following:
|cable. noun. 1. a plastic or rubber tube containing wires that carry telephone messages, electronic signals etc.
Unfortunately, when we explore the early attempts to provide a 'master receiver' subscriber radio service in the UK, the decades-later dictionary definition does not really define what they were doing. This is the point of confusion: decades later (as in past 1960), the British chose to refer to the late 20's developed service as a 'cable (service)'. The confusion arises from their use of the word 'cable' to describe something which in fact it was not. It was just one master receiver distributing audio frequency sound through one or more wires to paying subscribers.
Their dictionary definition of "cable" refers to "a plastic or rubber tube" when in fact virtually none of the early 'wired/piped radio' subscription services used such a contrivance. But — that confusion again — decades later when reporting on the 'wired/piped radio' era, they chose to call it "cable" when in fact it was — by their own dictionary — not.
British "Cable" TV
Where this takes us is beyond our primary topic (the origins of "cable TV")
but worth noting. Many other countries adopted modifications of this system;
Italy, for example, allowed 'private wire systems' to exist even though these wire operators created their own 'programming' to compete with the government owned stations (only government stations would be granted broadcasting licenses).
As late as the 1960s, American hotels of some size (100 rooms up) were installing 'wired radio' systems to feed either 540-1600 kc/s RF to individual in-room receivers, or following the British format, multiple wire pairs feeding in-room speakers from 'head end' demodulator/receivers. Each room was fitted with a 'station' selector switch. Some hotels offered as many as ten audio 'channels.'
In 1931, RCA introduced the 'Antenaplex' system for AM radio distribution in hotels and other large buildings. Technically, these systems look almost exactly like a 1950-60 hotel MATV system
down to signal splitters, taps, and line amplifiers.
So the British attempts to distribute off-air television from a common
antenna to multiple locations — were they first? Actually, no; that would
be the Germans, in 1936 — the same year BBC's first regularly scheduled television
The Heimann Superikonskop|
Although RCA would have preferred otherwise, attempts by the American firm to join efforts with British firm EMI did not happen. EMI had its own R & D
pre-Emitron (think iconoscope) project. Furthermore, EMI was sharing progress with German partners while Germany was also licensed by RCA's nemesis, the Farnsworth system, for their ongoing design work.
Bottom line: the Germans were quite capable of creating their own cameras. Six German-made cameras, known as the Superikonskop, designed by Herrn Prof. Dr. Heimann, were used for the 1936 Olympics transmissions.Photo: Nicolas Blazianu
Photo: Elektronenstrahlröhren - Vol. 2
For further information about the television cameras used at the 1936 Olympics, see the Early Televison Museum website.
But even that is slightly inaccurate. Before television signals could be distributed to two or more receivers connected to a common aerial, of course there had to be transmissions. Here the Germans did it first: by a matter of hours, days — possibly weeks — to spare, suitable camera designs appeared in Germany in time for the 1936 Olympics (August 1-16) held in Berlin (left sidebar).
The significance of the filmed telecasts of the 1936 Olympics in Berlin extends far beyond the technology of video transmission.
The director of these telecasts, German film director, actress and dancer Leni Riefenstahl, introduced numerous production techniques still in use by the filmmakers of today. Most startling at the time were such techniques as slow-motion photography, use of a crane to lift the camera for aerial shots, the use of tracking rails to follow the motions of athletes, and the use of several cameras simultaneously.
At the completion of the 1936 broadcasts, Riefenstahl assembled her footage into a feature-length film
still available on DVD today
in the 2012 edition of his annual Movie Guide
, describes Olympia,
Two-part record of the 1936 Berlin Olympics, highlighted by truly eyepopping cinematography, camera movement and editing. Of course, it's all supposed to be a glorification of the Nazi state. Various edited versions exist (some of which omit all footage of Hitler, who appears throughout the original print).
(Maltin, 2012, 1024).
Riefenstahl had pioneered many of these techniques in her previous work, notably her 1934 film Triumph of the Will, a documentary film of the 1934 Nuremberg Congress of the National Socialist Party. Maltin's take:
Riefenstahl's infamous documentary on Hitler's 1934 Nuremberg rallies is rightly regarded as the greatest propaganda film of all time. Fascinating and (of course) frightening to see.
(Maltin, 2012, 1453).
Screenshot from Triumph of the Will.
Riefenstahl lived to age 101, and traveled widely including visits to the United States. She has been described has an "acclaimed pioneer of film and photographic techniques" (Wikipedia) and as "one of the most admired film-makers of all time" (Amazon.com).
And to be totally accurate, even the term "live" needs clarification. The Germans
invented (here, "invented" is the correct word — the patent applications were filed in 1932) a system of rapid film development. In something between 60 and 90 seconds, a
newsfilm camera (17.5- or 35-mm) would shoot an event, the film would roll
instantly through a developer and equally instantly while marginally dry go
straight into a projector. The projector illuminated an attached early EMI- or Farnsworth-licensed TV camera. A photo-sensitive electron beam scanned a mosaic plate and by magic the almost-live filmed coverage appeared on TV receptors.
The Germans called these early Telefunken and Fernseh receivers "Volksceptors" (freely translated here; actually 'Volksfernseher') — think Volkswagen of later decades ("the people's television"). The broadcasts were 180-line definition, and later, 441-line definition, a function of the early release status of the rapidly-developing camera technology.
Sources disagree on the initial production run rushed to meet the 1936 Olympics but likely no more than 500 sets were delivered to quickly-created 'Public Television Offices' where the common folks (in two cities, Berlin and Potsdam) could watch up to 72 hours of 'almost live' Olympiad XI events on 7-, 9- and 12-inch screens. There are unverified reports of
4-foot wide projection screens as well.
These would be the first and last German 'mass produced' TV 'sets' before Europe became a war zone. References have the Germans producing an original run of 500 receivers in 1936, but later plans to build more for the 1939 Christmas season were the victim (with some humor now, so long after the fact) of the invasion of Poland by Germany and Russia in September, 1939.
Which has what to do with cable television? Surviving film of the 'Public Television Offices' of the German 1936 effort clearly depicts as many as a dozen receivers functioning simultaneously (remember the screen size limitation) in one building. If we reject the notion that each receiver had an individual directly-connected receiving antenna for the 42.9-megacycle signal, that says 'distribution network' of some sort, passive or active. Extant German technical literature from 1936-37 era leads to the conclusion that they employed RF-amplification in
their distribution networks.
If this is true, as it appears between the ancient film and yellowed burnt-edge technical papers in the original German, they did it first: they created technology to allow one 'master' antenna to service perhaps a dozen, even 50, receivers. But: was this 'community antenna television' or was it simply MATV?
Now, as a technology historian, it is not permissible to simply accept one source on something as potentially controversial as "who did it first". So if the 1936 evidence is less than 100%, we jump ahead to 1943 when the World War II was in full effect. An article in Issue No. 39 of the British publication After the Battle, titled TV Pictures from Occupied Paris, tells us that when the Germans captured Paris, in June 1940, they 'inherited' a functional Eiffel Tower French TV transmission system operating at 46 mc video/42 mc audio (Fig. 1). By 1943, it was linked to a pair of German transmitters (Berlin and Potsdam) that were used up to ten
hours daily to create programming for 'recuperation centers' (the German phrase
for where those of rank wounded in battle were being recycled for a return
to warfare). Those original 500 produced-in-1936 'Volksets' were retrofitted
into the recovery wards of these centers and a significant effort was put into
creating 'television programming' for those fortunate enough to be assigned to
such a facility. Three elaborate new — for the era — TV studios were constructed
in Paris, seating up to 500 audience members, including one with an on-stage swimming
Photo: Michael Ockenden, (After the Battle #39.)
Fig. 1. Test pattern from Fernsehsender transmitter, Eiffel Tower, Paris, ca. 1943. This photo was taken by Michael Ockenden, an RCAF
officer stationed in the UK during the Battle of Britain. During his tour of duty, he was based at a cliff-top listening post overlooking the English Channel
at Beachy Head, near Eastbourne, County of Sussex, UK, where he served as part of a team of WRNS and RAF personnel assigned to monitor German radio signals. They monitored navigational beacons, radar signals, radio-controlled bombs, and television signals from the Eiffel Tower.
Here there is less question about the distribution technology used. These systems employed master antenna distribution systems with amplification of the
off-air broadcasts, and fed as many as 50 sets in a single complex. You logically
don't do this with passive-only hardware (although it was possible and we
cannot be 100% certain of this).
Again, the question arises: CATV or MATV? We will dismiss that question as irrelevant to this narrative and proceed on the assumption the German systems used technology that would later be used in Astoria and Mahonoy City: community antenna television.
This (1943) would have been five years ahead of the Astoria, Oregon (or Mahanoy City, Pennsylvania) claims and two years before before the closed-down
BBC (television) restarted (June 6, 1946). Ah yes, the dissenters! Germany? Before the UK or USA?
A reminder of the purpose of this narrative: we are attempting to nail down
"the first systems which distributed television via cable to non-aerial
direct-connected sets." No, there is no evidence Germany employed 'coaxial'
cable but then what follows also does not qualify if it is 'coax' that
defines our objective.
There is precious little (let alone verifiable) evidence that anyone in the
UK attempted to take the Alexandra Palace 41/45 meg signal off air and
distribute it (at the reception frequency) via any kind of 'cable'
prior to the September 1, 1939 close-down of the transmitter (leaving it on the
air would have to provided German bombers with a 'homing device' in central London).
Now I should note at this point that at least one other author would perhaps dispute that statement. Patrick Parsons (quoting from a 1980 book by Kenneth Easton), writes:
By 1937, the firm [Radio Furniture & Fittings — see below] had installed TV antennas and amplifiers and was operating apartment house cable TV systems. . . . By 1939, some thirty or forty London buildings [had been wired].
Perhaps where Parsons erred or Easton's memory proved decades-challenged will be
clear with what follows. "Coaxial cable?" I think not.
Amplifiers? Again, I think not if we are talking 41/45 meg signals.
After the BBC restarted operations in June 1946, the story changes. Part of the
reason for this was a vastly improved post-war technology base (better circuits,
valves/tubes) but the major ingredient was the miserable state of the
British economy. Yes, BBC-TV was back, and yes a (very) small number of 'new'
post-war TV sets was available (essentially unchanged from 1939 designs; none initially had a
RF or tuner 'gain' stage).
But the economy was in the pits. So
at least one firm ― Radio Furniture & Fittings Ltd. ― explored recreating the wired radio concept for TV: customers would rent a TV receiver. Radio Furniture & Fittings (we'll call them Fittings) ran a 'cable' from a master off-air aerial, and by mid-1947, viewers in the tenements and row houses anticipated having television. Alas, the plan was technically flawed. And this overlooks the work that previously had been done in 1937-39 as reported in the April and July issues of TELEVISION and Short-Wave World. More about this shortly.
If the British engineers of 1937 could not or would not deal with direct-on frequency distribution, they did put into operation a rather unusual (even clever) 'intermediate' level of 'master antenna system'. Indeed, some Rediffusion history, without historical reference, claims that:
Fig. 2. Construction of master receiver located in roof shed, Arlington House apartment building, London.
Radio Furniture and Fittings Ltd. [in 1937] relayed the [BBC] television by cable, at the transmitted frequency, to blocks of flats on a CATV basis.
We will leave that report 'unverified' with a
reminder that, to the British, a 'wire pair' was 'cable,' following the Patrick
Parsons/Kenneth Easton quotation preceding. For the purposes of this narrative, we suggest below what we believe is more likely the accurate version.
The April 1937 issue of
Television and Short-Wave featured an article describing 'how multiple television receivers' might be placed on roll-around carts and provide television service to those confined to a hospital. The article hints it 'was being done' but neglects to be specific about where (suggesting it was more of a theoretical piece than a report about functional technology).
But the July 1937 issue of the same publication was much more explicit. An article titled Television Relays for Modern Flats notes that at several upmarket residential buildings in and around Piccadilly Square, a housing/shed on the roof of the building contained an off-air BBC single channel receiver (Fig. 2). The demodulated video and audio signals were then amplified and carried via wire pairs to newly-designed wall-mounted outlet plates in as many as 96 apartments (Fig. 3).
Special 4-prong plug used for Arlington House installation.
These installations were in top-of-market locations, quite the opposite of the British 'wired radio' systems in low-rent tenement districts. The article cites Arlington House as one such
building, and includes detailed system line drawings and photos of the installed equipment including the unusual (for 1937) wall outlet plate.
No, this was not a master antenna television network distributing signals at RF, but it was a master antenna service nonetheless. The in-apartment 'receivers' could have been either standard VHF TV sets, modified to accept baseband video and audio, or essentially AV monitors custom designed for this application. The July report states that each apartment unit required only a CRT "with an on-off switch, and brightness control," although doubtless an audio volume control was also included.
It all came to a halt of course on September 1, 1939, when Germany and Russia invaded Poland, sparking the start of World War II.
When BBC-TV restarted, the Alexandra Palace transmitter was not very powerful (5 kilowatts in 1946; 17 by 1950) but it was close to the northern-London suburbs. With the improved post-war technology, in 1947, Fittings initially attempted on-frequency RF distribution with two-wire pairs. Unfortunately, the TV sets connected to the 'master aerial' frequently ended up with three simultaneous images of BBC-TV:
Ghosting would be a mild term here. The history on this includes the
- The image from the off-air aerial.
- The slightly leading signal from the unintended aerial properties of the unshielded pair of wires strung across building fronts.
- The direct reception by the TV set's internal input wiring.
Some experiments [were attempted in 1946-47] with vision signals along cables using the 'off air' 45 mc/s carrier frequency but because of signal attenuation and severe ghosting the trial was abandoned.
(Remember: 'cable' equals 'wire pair' in the UK.)
Fittings was not giving up. In 1947, they would be responsible for what were
(apparently) the first in-wire-line (vacuum tube of course) 'RF line amplifiers'. Somehow they figured if the signal was kept at high enough level the unshielded, unintended, 'cable pickup' and the direct-to-the-TV-set internal wiring pickup would be tolerable. It was not. This would have to be classified as 'an experiment' that didn't work.
Fittings sold out to Rediffusion (including their
stable of 'wired radio' networks) in 1948, and Rediffusion, being slightly more
technically inclined, tried a different approach: if distribution at the
off-air frequency created intolerable pickup, change the input
frequency for 'cable' to a new one (keeping in mind that 'cable' was not coaxial cable, even though
plentiful supplies were available from WWII surplus outlets). These attempts presented new untested problems which neither Fittings nor Rediffusion seemed willing to seriously explore in 1947-48.
Returning to the (pre-war) Fittings on-roof shed approach, Rediffusion
elected to attempt wire-pair distribution by using a (much) lower vision
frequency: 9.72 mc/s, upper sideband (suppressed lower sideband). The BBC signal
was demodulated and the video used to remodulate the HF carrier, vision only;
audio would be transported as baseband audio in another wire pair.
In 1950, Rediffusion ran a field trial in the town of Margate. For this trail, 100 nine-inch Philips receivers were modified for 9.72-mc
video detection, with audio connected directly to the appropriate pair. It worked, not
flawlessly but well enough for Rediffusion engineering management to proclaim a
'Eureka!' moment. They called it the TDUK-1 system, setting the stage for a worldwide
effort that would ultimately attract nearly 500,000 paying subscribers including residents of
Montreal, Quebec. We will explore the UK 'cable TV' growth in subsequent parts of this narrative as most of it occurred after our 1948-1951 time frame.
The Margate trial also created several more 'Eureka-Moment' advantages:
- Cable loss at 9+ megs was far less than at the original off-air 41/45 megs so
the signals traveled further without need for (re)amplification in the 'pair
cable' in use.
- By eliminating the original 41/45 meg frequencies, the subscriber location no longer needed a full TV set with 41/45 input, but rather a simplified (vision-only) version that had the 9.72
mc IF (intermediate frequency) as an input. Significantly cheaper — perhaps 50% less — so subscriber fees became more profitable if Rediffusion also
supplied the receiver.
Fig. 4. The 9-inch Rediffuser receiver (1947).
Well, not quite. While 'line amplifiers' in the 9-mc range were very doable in that period,
there remained the problem with the cable itself. It was unshielded, and when carrying TV service it was assumed nobody else operating in the same frequency range (9-12 mc) would 'get
into' the system. Not true. The BBC's world-circling
short-wave transmitters also operated in the frequency range 9-12 megacycles, producing visible 'spark-gap' noise.
The bottom line for this exercise is simply this: Rediffusion pioneered an
IF-range distribution system for a single TV channel and in some areas
it worked while in others it didn't. But the concept of distributing signals at IF
rather than RF was now solidly entrenched at Rediffusion. And while
this is pages ahead of that timeline, when Canadian firm Benco announced their
pioneering transistorized T1 line amp (1959), it was designed to work over
a frequency range of 8 to 88 megacycles. The portion below North America's TV
Channel 2 (below 54 megs) was the result of Benco's belief that Rediffusion's Montreal system would need two channels (16 and 28 mc/s) in the basic Rediffusion format.
If we are searching for the first 'wire' distribution of television to
multiple locations where the 'wire' legally crossed (as with regulatory
permission) public streets and rights of way (ROW), this might be it — in late 1949, if we are generous, certainly before mid-1950 if we are less trusting
of the records. We will return there.
Continue to Part 2...