Thursday, 22 December 2011

[creative-radio] Dec 23 1900: First transmission of the human voice via radio by the Canadian inventor Reginald Fessenden (1866 - 1932)

Dec 23 1900: First transmission of the human voice via radio by the
Canadian inventor Reginald Fessenden (1866 - 1932) / 23 décembre 1900 :
Première transmission de la voix humaine à la radio par l'inventeur
canadien Reginald Fessenden (1866 - 1932).
US Weather Bureau contract and the first audio radio transmission

In 1900 Fessenden left the University of Pittsburgh to work for the United
States Weather Bureau<>,
with the objective of proving the practicality of using a network of
coastal radio stations to transmit weather information, thus avoiding the
need to use the existing telegraph lines. The contract gave the Weather
Bureau access to any devices Fessenden invented, but he would retain
ownership of his inventions. Fessenden quickly made major advances,
especially in receiver design, as he worked to develop audio reception of
signals. His initial success came from a barretter
which was followed by the electrolytic
consisted of a fine wire dipped in nitric acid, and for the next few
years this later device would set the standard for sensitivity in radio
reception. As his work progressed, Fessenden also evolved the heterodyne
principle <>, which
combined two signals to produce a third audible tone. However, heterodyne
reception was not fully practical for a decade after it was invented, since
it required a means for producing a stable local signal, which awaited the
development of the oscillating vacuum-tube.

The initial work took place at Cobb Island,
located about 80 kilometers (50 mi) downstream from Washington,
While there, Fessenden, experimenting with a high-frequency spark
transmitter, successfully transmitted speech on December 23, 1900 over a
distance of about 1.6 kilometers (one mile), which appears to have been the
first audio radio transmission. At this time the sound quality was too
distorted to be commercially practical, but as a test this did show that
with further technical refinements it would become possible to transmit
audio using radio signals.

As the experimentation expanded, additional stations were built along the
Atlantic Coast in both North Carolina and Virginia. However, in the midst
of promising advances, Fessenden became embroiled in disputes with his
sponsor. In particular, he charged that Bureau Chief Willis
Moore<>had attempted to gain
a half-share of the patents — Fessenden refused to
sign over the rights, and his work for the Weather
Bureau<>ended in August,
1902. (This incident recalled F. O. J. Smith, a member of
the House of Representatives from Maine, who had managed to gain a
one-quarter interest in the Morse telegraph.)

[Non-text portions of this message have been removed]


This e-mail service is edited, managed and moderated by
George Lessard

Messages posted here are now automatically posted on Twitter at:

Make a donation via PayPal:

Creative-Radio is an independent forum for people active in or interested in the use of radio in development, in particular promoting public health, improved education, protection of the environment, improved livelihoods, good governance and conflict mitigation. Since it started in 1996, Creative-Radio has been in the forefront of radio's resurgence as a tool for social change and peace-building, and it helps promote best practice in these areas.

Creative-Radio Moderator
Remove _NO_SPAM_ for use

RSS feed:

Change your subscription
- to daily digest mode by sending a blank message to:

- to individual e-mails by sending a blank message to:

- delivery on hold by sending a blank message to

Caveat Lector- Disclaimers, NOTES TO EDITORS
& (c) information may be found @
This work is licensed under a
Creative Commons Developing Nations license.
= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
Because of the nature of email & the WWW,
please check ALL sources & subjects.
Members who post to this list retain their copyright but grant a non-exclusive license to others to forward any message posted here. They also grant the list owner permission to maintain an archive or approve the archiving of list messages.
Other use of e-mail to this list requires the permission of individual writersYahoo! Groups Links

<*> To visit your group on the web, go to:

<*> Your email settings:
Individual Email | Traditional

<*> To change settings online go to:
(Yahoo! ID required)

<*> To change settings via email:

<*> To unsubscribe from this group, send an email to:

<*> Your use of Yahoo! Groups is subject to: