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This
was the operating room of WJY and WJZ in the Aeolian Hall Building, 1923. The
transmitters can be seen in line behind the operator’s desk.
The WJZ/WJY antenna was constructed on the roof of Aeolian Hall, at 29 West 42nd Street in New York City, in 1923.
This
famous photo shows inventor Edwin Armstrong performing acrobatics on one of the
WJZ towers on the roof of the Aeolian Hall, 400 feet above street level, on the
day of the station’s official opening in May, 1923. Armstrong reportedly did it to impress RCA
president David Sarnoff’s secretary, who later became his wife. Sarnoff was not amused, and declared the roof
to be permanently “off limits” to Armstrong.
An aerial view of the WJZ transmitter site in Bound Brook, NJ, near the Raritan River, 1926.
A WJZ engineer shows a rear view of one of the modulator
cabinets. The lineup of power tubes with
their water jackets attached can be seen at the top center of the cabinet. (Author’s collection)
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BEGINNINGS: WJZ debuted
on October 1, 1921, founded by Westinghouse Electric. Originally, the station was located in a
shack, accessible only by ladder, on the roof of a Westinghouse factory located
at Orange and Plane Streets in Newark, New Jersey. This was Westinghouse’s radio station – preceded
by KDKA in Pittsburgh and WBZ in Springfield, Massachusetts. The 500-watt WJZ transmitter was an exact
duplicate of the one built for KDKA. Before
long, a more comfortable two-room studio suite was opened inside the factory
walls.
WJZ
initially shared its 360 meter (833 kHz) frequency with several other New York
area stations until it was able to move to its own 455 meter (660 kHz) channel
in 1923. In May of that year, RCA
acquired the station from Westinghouse, and WJZ moved from the Newark factory to
the Aeolian Hall at 29 West 42nd St in New York, where it shared studio and transmitter
facilities with a sister station, WJY. Each
station had its own finely-decorated studio on the sixth floor, and there was
also a large glass-enclosed studio at street level that could be used by either
station. The two stations shared a
single antenna suspended from a pair of hundred-foot towers on the roof of the
building. RCA’s opulent new broadcast
complex was dubbed “Radio Central”. In 1926, RCA purchased AT&T’s showplace
station WEAF for $1 million, and its studios were moved over to Radio
Central. (WJY, the runt of the litter,
quietly disappeared from the air). The
purchase agreement included guaranteed access to AT&T long lines, and RCA immediately
established a network of several stations in the Northeast, which it called the
“WJZ Chain”. WEAF also had its own chain
of stations. Later in 1926, after RCA inaugurated
the National Broadcasting Company, this chain was expanded to become the NBC
Blue Network, and the WEAF chain became the Red Network. By that time, WJZ was operating with 1,000 watts
and WEAF with 5,000 watts.
MORE POWER FOR WJZ: Up through
mid-twenties, radio stations were still broadcasting with relatively low power,
and atmospheric noise and signal fading were significant impediments to
listener satisfaction, especially during the summer months. In 1925, five kilowatts was still considered
to be high power, and most stations were still operating with 1,000 watts or
less. To overcome the reception issues,
a group of major broadcasters pressured Secretary Herbert Hoover at the
Department of Commerce to authorize higher transmitter powers. Hoover responding by permitting higher
power on an experimental basis for a few stations – principally those belonging
to RCA’s “Radio Group”. Westinghouse
station KDKA was the first to be authorized, with 10 kW in 1924, later
increasing to 40 kW. In August, 1925,
General Electric’s WGY was permitted an experimental 50 kW, becoming the first
station in the country to operate at that power. In December, Hoover approved WJZ as the
country’s second 50 kW station – a fifty-fold increase from its Aeolian Hall
transmitter power. WEAF was to be the
fourth super-power station, and it would follow WJZ on the air in October,
1927.
Due to
concerns that such a powerful signal would overload the vast concentration of consumer
radios in the New York metropolitan area, a rural antenna location was
needed. RCA engineers scoured the
countryside within a 50 mile radius of New York, and finally chose a 54 acre
site at One River Road near the town of Bound Brook, New Jersey -- population
6,000 -- 35 miles West of New York. The
location was determined to have “excellent atmospheric qualifications for
broadcasting”. CONSTRUCTION:
RCA’s two
major manufacturing partners were awarded the contracts to build the
transmitters for WJZ and WEAF.
Westinghouse would build the WJZ transmitters, while General Electric
took on the WEAF project. The two
companies chose substantially different topologies, with the Westinghouse
design suffering from a number of technological limitations. It was simply a brute-force implementation of
the standard transmitters of the time -- essentially a free-running modulated
high-power oscillator (“self-excited”).
This was before the invention of crystal frequency control, and so they
required continuous monitoring and manual adjustment of the carrier frequency. Meanwhile, radio technology was advancing so
fast that the extra few months that G.E. had on the WEAF project resulted in a
much more modern device. It featured
crystal control, and used the MOPA (Master Oscillator – Power Amplifier)
configuration that would quickly become the standard for transmitter
construction. (See the December issue
for a full description of this transmitter).
Nonetheless, all of the transmitters built on this contract would be
obsolete and replaced in less than four years’ time.
The 30 x 70
foot two-story transmitter building that RCA built in Bound Brook was a virtual
duplicate of the one that RCA was building for WEAF about the same time at
Bellmore, Long Island. The attractive
colonial-style building was designed to blend in with the rural, residential environment. However, inside it was strictly a serious commercial
structure. All of the power and
mechanical equipment was located in the basement, with the transmitting and
operating equipment being housed on the second floor. External structures behind the transmitter
house included a power substation, an antenna tuning network, and a heat
exchanger for the recirculating water-system that cooled the transmitter tubes.
The 450
meter antenna was a conventional T-type design, supported by two 300 foot
towers. They were separated by 700 feet,
although the horizontal antenna itself was only 220 feet long. It consisted of a six-wire horizontal cage
with a download wire in the center. At
both ends, the antenna halyards ran through pulleys atop the tower down to
2,000 lb. suspended concrete counter-weights which maintained the proper
tension on the antenna. The antenna was
fed through a tuning network installed in a hut located directly under the
antenna. Motor-operated variable air
capacitors were adjusted by remote control from inside the transmitter
building.
In addition
to WJZ’s normal frequency of 455 meters (660 kHz), there was also a shortwave
transmitter operating on 100 meters (2,998 kHz). The antenna for this station consisted of a
vertical copper pipe mounted on a wooden pole.
A loading coil with an antenna current meter were located in the center
of the antenna.
The local electric
utility delivered 3 phase 4,400 volt power to the Bound Brook building. In the basement, huge transformers converted
this to 10,000 volts needed for the transmitter plate voltages. This voltage was sent upstairs to the
rectifier tubes, and then it returned to the basement where the filter
capacitors and chokes were located. Also
in the basement, a duplicate pair of motor-generators provided 15 volts for the
tube filaments.
There were
three transmitters on the main floor:
duplicate 450 meter transmitters and a 100 meter shortwave
transmitter. Each one consisted of three
independent open-frame panels – the rectifier panel contained six rectifier
tubes; the oscillator panel had eight tubes; and the modulator panel had
twelve. All of these tubes were cooled
by a closed-circuit circulating water system that ran 3,300 gallons per minute
of distilled water through an outdoor heat exchanger cooling tower. Also on the main floor, a large seven-panel
switchboard controlled the power for all equipment. There was also an operator’s audio control
panel in a separate room. ON THE AIR:
On December
7, 1925, WJZ fired up the new Bound Brook transmitter for the first time, broadcasting
with the experimental call sign 2XAR. The
response from Bound Brook residents was instantaneous -- they complained that
the powerful new signal was blanketing out all other stations on their
radios! In just a few weeks, the
Department of Commerce received 1,500 letters of complaint from unhappy
listeners. Herbert Hoover noted: “This
particular station (WJZ) has been broadcasting for some ten days using about
forty kilowatts of power. This is a very
large amount, and the department has received a considerable amount of
complaints from broadcast listeners in its immediate vicinity.“ Until the problem could be rectified, Hoover
ordered WJZ’s power reduced to 5 kW.
RCA sent out teams of engineers to visit homes in Central New Jersey to
deal with the complaints, but this effort had limited results. The principal cause of the problem was the
lack of selectivity in the early TRF and regenerative radios that consumers
owned. They were designed to pick up the
weak signals of the early and mid-twenties and were simply overwhelmed by such
a strong local signal. The more
selective super-heterodyne receivers were just starting to come onto the market,
but they were expensive and limited to a handful of models being made by RCA,
who jealously controlled the patents on the technology. Also, the AVC (automatic volume control)
circuit had yet to be invented. The final
solution to WJZ’s problem would have to wait for the next generation of
receivers to reach consumers’ hands. In
April of 1927, WJZ was permitted to increase its power to 45 kW, but after a
barrage of new complaints over two months, it was ordered to cut back to 30
kW. The station stayed at that power
until the F.C.C. finally authorized 50 kW full time operations in 1935. The Westinghouse transmitter was replaced
with a more modern and stable RCA 50B in 1931, although it remained in place as
a standby transmitter for a few more years. THE FIGHT FOR SUPER POWER:
RCA
engineers and the Department of Commerce analyzed the results of these first
experiments in high power radio broadcasting.
They determined that high power produced louder signals and reduced
atmospheric noise over a larger area, but that the gain was not proportional to
the amount power increase. Nonetheless,
the 50 kW experiment had proven successful, and several dozen stations around
the country – principally on clear channel frequencies – were on the air at
that power level by the early thirties. Other methods to improve radio
reception would soon be explored, including a conversion from the flat-top “T”
antennas to vertical radiators above a ground system, which dramatically
improved ground wave reception. In 1936,
WJZ would build a 640 foot anti-skywave tower at Bound Brook that would more
than double its nighttime coverage.
Another
solution being considered to reception issues was a further increase in power –
this time up to 500,000 watts. In
Cincinnati, Powel Crosley’s WLW was given the experimental authority to operate
at that power. For that project,
Westinghouse, General Electric and Westinghouse all combined forces to build a
monstrous two-story transmitter. When it
went on the air in 1934, its primary daytime coverage area encompassed six
states, and at night it covered the entire eastern half of the country. With this kind of coverage, WLW essentially
became a one-station network, and Crosley was making money hand-over-fist in
spite of the immense power bill.
Many other
broadcasters observed the Cincinnati gold mine, and decided they wanted in on
the action. In short order, a number of
stations around the country, including WJZ and WEAF, had also filed for
super-power authority. This created a
political problem for the F.C.C., because the AM band was unable to support
very many of these stations without sacrificing local service. The battle eventually became politicized and it
ended up in the halls of Congress, who in 1939 finally settled the matter by
declaring a 50,000 watt ceiling for all broadcast stations in the United
States. WLW was ordered to reduce power to 50,000
watts on March 1, 1939.
At one point
in these negotiations when the outcome seemed more positive, RCA had been
confident enough to build a 500 kW transmitter for WJZ, which became a white
elephant after Congress’ decision. RCA
eventually sold it to the British Secret Service for £165,000. It was shipped to the U.K., where it was
placed in service during World War II as the famous black propaganda station Aspidistra. WJZ VACATES THE BOUND BROOK SITE:
WJZ saw a
number of other changes and improvements over the succeeding years. In November of 1928, it moved from 660 to 760
kHz, with sister station WEAF taking over the 660 frequency. In 1941, it moved again to 770 kHz as part of
the nationwide NARBA frequency shift
In October
of 1943, under an anti-monopoly court order, NBC sold the Blue Network, including
its key station WJZ, to Edward J. Noble, and it became the American
Broadcasting Company (ABC). In January,
1944, the WJZ transmitter was relocated to a new tower on Route 17 near Lodi,
New Jersey. NBC continued to operate
Bound Brook as a shortwave facility for its stations WNBX and WNBC until the
end of World War II. The site was then shut
down, and today it is part of a housing tract.
In 1953,
WJZ’s call sign was changed to WABC, to reflect its role as the key station of
the ABC network. (This should not be
confused with CBS’s New York station, which had been known as WABC for many
years but became WCBS in 1946.) WABC
continues to operate today on 770 kHz with 50 kW from the Lodi site. The WJZ call letters were brought out of
retirement by Westinghouse in 1957, and continue to be heard today, on AM, FM
and TV stations in Baltimore.
BIBLIOGRAPHY AND REFERENCES:
-
The Beginning of Broadcast Regulation
in the Twentieth Century by Marvin R. Bensman
- History of Radio to 1926 by Gleason Archer
- “Scientific American”
Magazine, March, 1922. “Radio For Everybody”
- “The
Electragist”, 1923, Vol. 22 No. 9, pg. 58
- “Wireless
Age” Magazine, July, 1923. “Radio
Broadcast Central”
- “Radio World”
Magazine, Jan. 23, 1923 – page 16.
“Monster radio tower installed on roof of New York Skyscraper” by Robert
L. Dougherty
- “Radio News”,
January, 1925
- “Boys Life” Magazine, February 1926, page
26. “Through Stations WJZ and WGY (sic)”
- “Wireless World” Magazine, March 31,
1926, page 495. “America’s New High
Power Broadcasting Station” by A. Dinsdale.
- “Radio News” Magazine, April 1926, pg.
1405. “Views of the New Super-Power
Station WJZ”.
- “Boys Life” Magazine, December 1927,
page 68, “Sparks Visits WEAF’s New Home”
- “WJZ and WJY,
Fraternal Twins”, Arcane Radio Trivia, http://tenwatts.blogspot.com/2013/12/wjy-and-wjz-fraternal-twins.html
- "Tower site
of the week” by Scott Fybush, May 27, 2005. http://www.fybush.com/sites/2005/site-050527.html
- Wikipedia
articles about WABC, WJZ-TV, Aspidistra
- An Aerial view of the WJZ tower site
at Bound Brook can be viewed here:
Library Company of Philadelphia, digital collections
http://lcpdams.librarycompany.org:8881/R/?func=dbin-jump-full&object_id=61818&local_base=GEN01
NOTE:
This article appeared in the Spectrum Monitor Magazine, July, 2016.
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