"Crazy George" wrote
I'm afraid you're way behind the practice on this one. In the US,
there are
many 4, 5 and 6 tower arrays providing as many nulls to protect
co-channel
stations.

=================================

What proportion of US MF broadcasting stations have antennas
consisting of more than two towers ?
----
Reg.

Reg, G4FGQ wrote:
"What proportions of U.S. broadcasting stations have antennas consisting
of more than two towers?"

I don`t know but from my own experience, the number is large. A new
applicant for a station must show he will not interfere with existing
stations by limiting his radiation in the directions of the existing
stations while providing minimum field intensity, 0.5 to 50 mV,
depending on population, in the new service area. A two-tower array
cannot satisfy some complicated pattern requirements.

Most broadcasters want to provide more than 1 KW radiation in their
areas. Well over one hundred channels in the medium wave broadcast band
in North America allow that. There are well over 1000 regional medium
wave broadcasters in North America. It is difficult to fit a new
broadcaster in when he wants to use real power.

Best regards, Richard Harrison, KB5WZI

Richard Harrison wrote:
I don`t know but from my own experience, the number is large.

I would guess that the majority of US AM antennas that I
have seen with my own eyes have more than one element.
--
73, Cecil http://www.qsl.net/w5dxp

Reg:

I don't have an accurate number for the entire country, but here in the
local area, there is one clear channel station with a single radiator, a
half dozen two tower arrays, two 3 tower arrays, five 4 tower arrays that I
can recall off the top of my head. If you had asked a dozen years ago, I
could have been more accurate. I don't think we have any 5 or 6 radiator
arrays here locally, if so, I don't remember them. If my math is correct,
that is a 50-50 split, so maybe half have more than 2 towers.

--
Crazy George
W5VPQ
My real address is my ham call atARRL.NET The ATTGlobal is a SPAM trap.
"Reg Edwards" wrote in message
...

"Crazy George" wrote
I'm afraid you're way behind the practice on this one. In the US,
there are
many 4, 5 and 6 tower arrays providing as many nulls to protect
co-channel
stations.

=================================

What proportion of US MF broadcasting stations have antennas
consisting of more than two towers ?
----
Reg.

"Crazy George" wrote
I don't have an accurate number for the entire country, but here in
the
local area, there is one clear channel station with a single
radiator, a
half dozen two tower arrays, two 3 tower arrays, five 4 tower arrays
that I
can recall off the top of my head. If you had asked a dozen years
ago, I
could have been more accurate. I don't think we have any 5 or 6
radiator
arrays here locally, if so, I don't remember them. If my math is
correct,
that is a 50-50 split, so maybe half have more than 2 towers.

=======================================

Thanks George,

I am amazed at the number of multi-tower MF antennas in the US. As you
say, they are necessary to prevent co-channel interference, day and
night, between a large number of broadcasters in the more densely
populated regions of your vast country. ( Antenna salesmen have had a
field day.)

It is also interesting that the whole system is technically regulated
by State and/or Central Government. It is not just a free-for-all for
newcomers.

I imagine the revenue comes solely from advertisers. Which makes me
wonder what percentage of program time is allocated to adverts. Are
such matters also regulated? Are any broadcast stations State or City
owned?

In this (UK) relatively densely populated country things settled down
about 20 years ago. Few MF antennas have more than one tower (or masts
as we call them). Although there is much broadcasting at MF for
individual cities, most broadcasting takes place at FM VHF where
'capture effects' reduce interference from co-channel transmitters.

It may be of interest that the BBC, still the World's finest
broadcasting system, including its overseas services, no longer owns
any transmitting stations, Mrs Thatcher quietly sold them off to a
private party. Do some Googles for who the eventual owners are?
----
Reg.

Reg Edwards wrote:

SNIPPED


I imagine the revenue comes solely from advertisers. Which makes me
wonder what percentage of program time is allocated to adverts. Are
such matters also regulated? Are any broadcast stations State or City
owned?

$$$ from advertisers ... YEP!

Amount of advertising time is regulated. I can't state with any
authority, but it seems to be 15 to 20 minutes per hour.

Ownership is generally private. International propaganda, err news, may
be indirectly government controlled through a straw man corporation.
Certain public service stations, e.g. WWV, are government 'owned'.

An several additional non sequitor comments. In the USA, although we
claim FREE ENTERPRISE, it is a government influenced economy via
interest rates, international treaties, anti-trust regulations, etc.

Finally, the USA is succumbing to a creeping Socialism. This is contrary
to the words of John F Kennedy: "Ask NOT what your country can do for
you; ask what you can do for your country." Forty-five years after that
statement from President Kennedy a large portion of the population want
the government to do everything for them.

A Keag


In this (UK) relatively densely populated country things settled down
about 20 years ago. Few MF antennas have more than one tower (or masts
as we call them). Although there is much broadcasting at MF for
individual cities, most broadcasting takes place at FM VHF where
'capture effects' reduce interference from co-channel transmitters.

It may be of interest that the BBC, still the World's finest
broadcasting system, including its overseas services, no longer owns
any transmitting stations, Mrs Thatcher quietly sold them off to a
private party. Do some Googles for who the eventual owners are?
----
Reg.

Amos Keag wrote:
Finally, the USA is succumbing to a creeping Socialism. This is contrary
to the words of John F Kennedy: "Ask NOT what your country can do for
you; ask what you can do for your country."

Methinks you completely missed Kennedy's meaning. Here's Ayn
Rand's take on that statement: "Ask NOT what your country can
do for you ...", translation: Stop expecting the federal government
to preserve and protect your individual constitutional rights;
"... ask what you can do for your country.", translation: give up
your constitutional rights, including your life, liberty, and
possessions, in order to benefit the welfare state.
--
73, Cecil http://www.qsl.net/w5dxp

Cecil Moore wrote:

Amos Keag wrote:

Finally, the USA is succumbing to a creeping Socialism. This is
contrary to the words of John F Kennedy: "Ask NOT what your country
can do for you; ask what you can do for your country."


Methinks you completely missed Kennedy's meaning. Here's Ayn
Rand's take on that statement: "Ask NOT what your country can
do for you ...", translation: Stop expecting the federal government
to preserve and protect your individual constitutional rights;
"... ask what you can do for your country.", translation: give up
your constitutional rights, including your life, liberty, and
possessions, in order to benefit the welfare state.

YEP!!! Socialism.

Reg, G4FGQ wrote:
"It is also interesting that the whole system is technically regulated
by State and/or Central Government."

In the beginning, there was no regulation. There were only wireless
experimenters. Marconi invented the antenna which made the signal go
far. Marconi`s antenna may have been seen as an elevated capactor plate.
When the transmitter and receiver were each equipped with a plate, you
had a coupling capacitor with the earth for a return path. The capacitor
carries displacement current while the earth moves electrons.. Then,
Marconi discovered the capacitor leads worked well enough without the
plates, so plates were omitted.

Marconi was soon using wireless for ship to shore communications. It was
essential to safety of life at sea. When the Titanic sank on April 15,
1912, it had a Marconi operator aboard. The world was immediately aware
of radio. Inept radio communications during the loss of the Titanic
prompted the U.S. Congress to pass the Radio Act of 1912, which expanded
on the Wireless Ship Act of 1910 which required all seafaring vessels to
maintain 24-hour radio watch and keep contact with nearby ships and
coastal radio stations.

All radio communications were in code until Reginald Fessenden invented
wireless telephony in 1906. In the early wireless days a lidtener had to
understand code to make sense of wireless.

The Radio Act of 1912 assigned three-letter and four-letter codes
(call-letters) to radio stations and limited broadcasting to 340 meters.
This jammed the signals. From the beginning, the U.S. Federal Government
declared sole jurisdiction over radio as the waves don`t stop at state
lines and must involve international cooperation. It`s the "Interstate
Commerce Regulation Power" of the Federal Government.

In 1920, KDKA in Pittsburgh, a Westinghouse station, transmitted the
first commercial radio broadcast.

In 1922, the U.S. Commerce Department allowed powerful stations to use
400 meters, as long as they only broadcast music.

In 1925, A,C. Nielsen began reporting audience shares to advertisers,

In 1925, the first soap opera (The Smith Family) was broadcast.

In 1926, RCA, General Electric, and Westinghouse established The
National Broadcasting Company (NBC). NBC operated two networks of
stations (Red & Blue).

In 1929, William S. Paley founded The Columbia Broadcasting System
(CBS).

In 1931, there were 40,000 U.S. TV sets, including 4,000 in New York
City.

In 1933, Edwin Armstrong introduced Frequency Modulation.

The Communications Act of 1934 created the Federal Communicationsd
Commission which regulates broadcasting.

In 1936, The British Broadcasting Corporation (BBC) debuted the world`s
first television service with three hours of programming a day.

In 1937, Edgar Bergen and Charlie MCCarthy debuted on NBC TV.

We live in interesting times.

Advertising pays for broadcasting in the U.S. except for some public
support of non-commercial or almost non-commercial stations.

Program time devoted to advertising on commercial stations was limited
by the FCC to just a few minutes per hour before Carter became
president. He started the deregulation process which has now run amok.
Commercial announcements were the topic of "Saturday Night Live".
Satirically, they entertain.

Mrs. Thatcher may have sold the BBC`s distribution facilities, but since
BBC has done so well programming, I hope the production facilities are
still in the hands of those responsible and that they continue and grow
their product.

Who bought the BBC`s transmitters depends on how big the bargains were.
If a windfall was readily available, I suspect the Queen, her relatives
and allies may have been the buyers. Like Russia, I suppose, except with
more care that the buyers seem not to be profiteers.

My daughter lives in London and pays her tax to support the BBC. She now
owns a 99-year lease on her flat in Westminster. Only leases are
available. The right people are the ownwers and they aren`t selling. Her
married name is Edwards too, but her husband is an American. They are
both lawyers.

Best regards, Richard harrison, KB5WZI

On Tue, 8 Nov 2005 14:11:07 -0600, (Richard
Harrison) wrote:

All radio communications were in code until Reginald Fessenden invented
wireless telephony in 1906. In the early wireless days a lidtener had to
understand code to make sense of wireless.

Hi Richard,

Oddly enough, just before a Nanotechnology seminar, I was recently
browsing:

"The Radio Amateur's Handbook
A Complete, Authentic and Informative
Work on Wireless Telegraphy and Telephony"

by A. Frederick Collins
Inventor of the Wireless Telephone, 1899

To William Marconi
Inventor of the Wireless Telegraph

"The wireless telephone was invented by the author
of this book at Narberth, Penn., in 1899, and his first
experiments the human voice was transmitted to a
distance of three blocks."

Awarded Gold Medal for same, Alaskan Yukon Pacific Exposition [now the
campus of the University of Washington from which I have just returned
from minutes ago], 1909.

....

"After Marconi had shown the world how to telegraph without
connecting wires it would seem , on first thought, to be an easy
matter to telephone without wires, but not so, for the electric
spark sets up damped and periodic oscillations and these cannot be
used for transmitting speech. Instead, the oscillations must be
of constant amplitude and continuous. That a direct current arc
light transforms a part of its energy into electric oscillations
was shown by Firth and Rogers, or England, in 1893.

"The author was the first to connect an arc lamp with an
aerial and a ground, and then to use a microphone transmitter
to modulate the sustained oscillations so set up. The receiving
apparatus consisted of a variable contact, known as a pill box
detector, which Sir Oliver Lodge had devised, and to this was
connected an Ericsson telephone receiver, then the most sensitive
made. A later improvement for setting up sustained oscillations
was the author's rotating oscillation arc."

This volume is available at Project Gutenberg as an e-book. Collins
goes on to describe the "boys" who monitored shipping transmissions
and often joined in:

"boys began to get great fun out of listening in to what the ship
and shore stations were sending and, further, they began to do a
little sending on their own account. These youngsters, who caused
the professional operators many a pang, were the first wireless
amateurs, and among them experts were developed who are the
foremost in the practice of the art today."

It should be noted that "hackers" of a decade ago now fill much the
same description, and have been similarly elevated.

73's
Richard Clark, KB7QHC