As Hams, we routinely use "73" for a closing (or opening) salutation. Here
is an excerpt from the QSL.net website that offers an explanation of the origin of "73."
http://www.qsl.net/w5www/73.html#73 (lots of good indo here)
THE ORIGIN OF 73
(Via Louise Ramsey Moreau, W3WRE, & Charles
A. Wimer, KC8EHA)
The following is from Louise Ramsey Moreau, W3WRE:
expression "73" goes right back to the beginning of the landline telegraph days. It is found
in some of the earliest editions of the numerical codes, each with a different definition,
but each with the same idea in mind - it indicated that the end, or signature, was coming
up. But there are no data to prove that any of these were used.
The first authentic
use of 73 is in the publication "The National Telegraphic Review and Operators' Guide", first
published in April 1857. At that time, 73 meant "My love to you"! Succeeding issues of this
publication continued to use this definition of the term. Curiously enough, some of the other
numerals used then had the same definition as they have now, but within a short time, the
use of 73 began to change.
In the National Telegraph Convention, the numeral was changed
from the Valentine-type sentiment to a vague sign of fraternalism. Here, 73 was a greeting,
a friendly "word" between operators and it was so used on all wires.
In 1859, the
Western Union Company set up the standard "92 Code." A list of numerals from one to 92 was
compiled to indicate a series of prepared phrases for use by the operators on the wires. Here,
in the 92 Code, 73 changes from a fraternal sign to a very flowery "accept my compliments",
which was in keeping with the florid language of that era.
Over the years from 1859
to 1900, the many manuals of telegraphy show variations of this meaning. Dodge's "The Telegraph
Instructor" shows it merely as "compliments." The Twentieth Century Manual of Railways and
Commercial Telegraphy defines it two ways, one listing as "my compliments to you"; but in
the glossary of abbreviations it is merely "compliments". Theodore A. Edison's Telegraphy
Self-Taught shows a return of "accept my compliments". By 1908, however, a later edition of
the Dodge Manual gives us today's definition of "best regards" with a backward look at the
older meaning in another part of the work where it also lists it as "compliments".
"Best regards" has remained ever since as the "put-it-down-in-black-and-white" meaning
of 73 but it has acquired overtones of much warmer meaning. Today, amateurs use it more in
the manner that James Reid had intended that it be used - a "friendly word between operators".
I hope that this helps you in some way....
Charles A. Wimer
Amateur Radio Call: KC8EHA
Assistant Emergency Coordinator, Trumbull County (OH)
ARRL Official Emergency Station (OH)
- Kirt Blattenberger
RF Cafe Progenitor & Webmaster