Post by Tak ToWell, ABC, for example, is a network of stations that air shows,
not a network of shows.
Well, it's a distributor that funnels money from broadcast stations to
program producers (including its parent company Disney), and operates
a satellite and terrestrial transmission system that allows the
stations that pay it money to live-stream those shows or download them
for later broadcast, including the right to insert locality-specific
advertising.
ABC began its life as the Blue Network of NBC, but even in the 1930s,
the "network" per se was owned and operated by the Bell System, not
NBC. AT&T operated the telephone lines that connected New York and
Chicago, Los Angeles and San Francisco, leased access to them to the
four radio networks, and was responsible for delivering the audio
signals to and from each affiliate station by connecting them to Long
Lines offices. The network signal might be carried through the cities
where the networks operated, but only rarely did they actually go
through the *stations* -- in modern graph-theoretical terminology,
AT&T Long Lines owned and operated all of the internal nodes, and
reconfigured them into a spanning tree rooted at whichever node was
nearest the origination point for a particular network program; the
network affiliates were (nearly) all leaf nodes. Many networks also
distributed prerecorded programs on transcription disks (like
long-playing records, but earlier technology, typically recorded on
aluminum blanks).
The signal degradation inherent in retransmitting AM signals was such
that this was rarely done -- if you could get a good enough signal
from a neighboring station to retransmit, that probably meant that you
were witin that station's exclusive territory and wouldn't be allowed
to affiliate with the same network (at least not on a primary basis).
You didn't see real over-the-air networking until the late 1930s when
the superior noise floor of VHF-FM radio made it practical. The
earliest FM network broadcasts occurred over Major Armstrong's
station, W2XMN in Alpine, New Jersey, and were retransmitted by
Franklin Doolittle's station in Connecticut (I think W1XPW?) and the
GE station in Schenectady. Later, the commercial Yankee Network in
New England, the Rural Radio Network in Upstate New York, and the
Concert Network in New York and southern New England used similar FM
rebroadcast technology. However, although FM had much lower noise
than AM, especially during summer weather, it was still higher than a
direct telephone line, and of course depended on every station on the
chain operating properly, carrying the same programming, and paying
attention to the network cues, so this system fell out of use by the
end of the 1970s. Some translators are still fed this way.
-GAWollman
--
Garrett A. Wollman | "Act to avoid constraining the future; if you can,
***@bimajority.org| act to remove constraint from the future. This is
Opinions not shared by| a thing you can do, are able to do, to do together."
my employers. | - Graydon Saunders, _A Succession of Bad Days_ (2015)