[SFDXA] FIRST AMATEUR TRANSATLANTIC HF DIGITAL VOICE QSO REPORTED

[Bill Marx]

>From ARRL Letter:

FIRST AMATEUR TRANSATLANTIC HF DIGITAL VOICE QSO REPORTED

Radio communication pioneers Ten-Tec and Thales have announced that
they've used an Amateur Radio linkup to span the Atlantic on HF digital
voice for the first time. Ten-Tec's Doug Smith, KF6DX, and Thales' Didier
Chulot, F5MJN, successfully transmitted and received HF digital speech
signals November 22 between Paris, France, and Ten-Tec's Sevierville,
Tennessee, headquarters.

"We view this as a significant accomplishment," said Smith. "Amateur Radio
has long been at the forefront of technological development. It's nice to
be able to show that our legacy is alive and well." Tests are being
conducted under the auspices of ARRL's Digital Voice Working Group, which
Smith chairs. A written report on the tests is due in January.

Calling it "a major breakthrough," a Ten-Tec news release said the two
amateur stations "demonstrated the advantages of digital audio during the
conversation, including noise-free, FM-like reception and the potential
for simultaneous voice and data." The feat was accomplished on 15 meters
using Ten-Tec transceivers and Thales Communications Skywave 2000 digital
audio software. Operating as F8KGG, Chulot spoke with Smith for several
minutes over the HF digital link, operating within a 3-kHz bandwidth.

Smith said he and F5MJN used unmodified Ten-Tec transceivers in
upper-sideband mode, although AM or FM mode also would work. No additional
hardware was required beyond the cables connecting the transceiver and the
microphone to the PC sound card. Smith said audio quality was roughly the
same as a conventional telephone circuit. An Amateur Radio version of the
Thales system is expected to appear on the market early next year. "At
this stage, the system is experimental-only for ham radio, but it looks
like it's going to take off," Smith predicted.

In terms of Amateur Radio, Alinco was the first manufacturer to come out
with a digital voice option for some of its transceivers. ICOM debuted its
D-Star digital "concept radio" system last May at the Dayton
Hamvention--where Smith chaired the Digital Voice Forum--and demonstrated
it at the ARRL-TAPR Digital Communications Conference in September. The
unit, which operates on 1.2 GHz, was scheduled to hit the ham radio market
this fall.

Technical details of the Thales system will appear in an article
"International Digital Audio Broadcasting Standards: Voice Coding and
Amateur Radio Applications" in the January/February issue of QEX, which he
edits. The article is available on the ARRL Web site
<http://www.arrl.org/tis/info/pdf/x0301049.pdf>. He also has authored two
articles on digital voice in QST: "Digital Voice: The Next New Mode?"
<http://www.arrl.org/tis/info/pdf/0201028.pdf> in the January 2002 issue,
and "Digital Voice: An Update and Forecast"
<http://www.arrl.org/tis/info/pdf/0202038.pdf> in the February 2002 issue.

Additional images and background are available on the TAPR Web site
<http://www.tapr.org>. Look for the Digital Voice Forum page and the
presentation by C�dric Demeure.--Ten-Tec news release; Doug Smith, KF6DX