Introduction

High-quality voice communication is possible without exceeding SSB bandwidth or expensive broadcast studio equipment

Practical HF Digital Voice shows how two British hams built modems at a reasonable cost to accomplish PSK31-like communications on voice.

Articles

Note: Some of the following articles are in Adobe Portable Document Format (PDF) files. To view and print these files, you'll need a copy of Adobe's Acrobat Reader program. (Version 3.0 or later required). More information here.

• Practical HF Digital Voice
  QEX May 2000, pp. 3-8
  High-quality voice communications using modems.
• International Digital Audio Broadcasting Standards: Voice Coding and Amateur Radio Applications (795,890 bytes PDF file)
  QEX January/February 2003, pp. 49-56
  A digital-voice standard for broadcast and Amateur Radio.
• PTC: Perceptual Transform Coding for Bandwidth Reduction of Speech in the Analog Domain, Pt 1 (200,799 bytes PDF file)
  QEX May/June 2000, pp. 9-12
  A new method for optimizing the bandwidth of phone signals using sound perception.
• PTC: Perceptual Transform Coding for Bandwidth Reduction of Speech in the Analog Domain, Pt 2 (310,988 bytes, PDF file)
  QEX March/April 2001 pp. 9-17
• JAIA's Universal Standard D-Star (209,359 bytes, PDF file)
  CQ Ham Radio Magazine. Reprinted with permission.
  A overview of a digital communication standard as presented at the At HAM Fair 2001, in Japan.
• Digital Voice: The Next New Mode? (145,675 bytes, PDF file)
  QST January 2002, pp. 28-32
  A brief tour of this technology and it’s place in Amateur Radio.
• Digital Voice: An Update and Forecast ( 539,648 bytes, PDF file)
  QST February 2002, pp. 38-41
  What hams are doing with digital voice now and what about the future?

Note:

Contact information for suppliers mentioned in the above articles should first be confirmed using TIS Address Database Search.

Bibliography (Members Only)

ARRL Periodicals Index Search - This database contains the QST index from 1915 to the present and the QEX index from 1981 to the present. For QST issues from 1970 to the present, and some selected articles back to 1922 (when construction articles featuring tubes began in earnest), identifying keywords have been added to the technical articles. By entering keywords (ANTENNA) or combinations of keywords (CONSTRUCTION ANTENNA VERTICAL HF) into the Title words: field, you may create dynamic bibliographies.
Technical article KEYWORD list. Hints for more successful searching

Web Links:

• Advanced Technology in Amateur Radio video - Talk given by Doug Smith, KF6DX, QEX Editor at Georgia Tech, March 10, 2003. Windows WMV format, 110 minutes.
• Digital/Analog Voice Demo
  This is a comparative demonstration of some digital and analog voice transmission alternatives for the power-limited amateur satellite channel.
• RAC Digital Modes page
  Links to tutorials and other information on Digital Speech
• USPTO Patent Information page
  "A link to the PTO and a mention that copies of patents can be obtained free would be useful. Uncle Sam has only recently made them available at no charge. You can search the database using keywords like '' speech codec', etc. Lots of good stuff there." Doug, KF6DX
• Digital Voice on H.F
  Charles Brian, G4GUO, co-author of Practical HF Digital Voice
• Digital Voice Systems
  AMBE vocoder chip manufacturer
  
• Link to RAC Digital Mode page
  Links to tutorials and other information on Digital Speech
• The Start of the Digital Revolution
  SIGSALY Secure Digital Voice Communications in World War II
• TAPR (Tucson Amateur Packet Radio)
  An international organization of over 2000 members with interests in the areas of packet and digital communications. TAPR is a membership-supported, non-profit organization dedicated to amateur research and development. This page has links to a number of project web pages, special-interest email reflectors and membership information. (How to become a member of TAPR)
• Digital Voice Project
  K3TU Temple University Amateur Radio Club
• TAPR Digital Voice Forum
  Slides from the Digital Voice Forum at Dayton Hamvention 2002.

Article Reprints:

You can get a photocopy of any ARRL published article for $3 ($5 for nonmembers) for each article requested. Contact the ARRL Technical Department (reprints@arrl.org ), 1-860-594-0390) if you wish to get photocopies.

This information was prepared as a membership service by the American Radio Relay League, Inc., Technical Information Service, 225 Main St., Newington, CT 06111 (860) 594-0214. Email: tis@arrl.org (Internet). ARRL HQ is glad to provide this information on the Web free of charge as a service to League members and affiliated clubs.

If you have any questions concerning the reproduction or distribution of this material, please contact:

TIS Coordinator
American Radio Relay League
225 Main St., Newington, CT 06111
Tel: 860-594-0214 Fax: 860-594-0259
(email: tis@arrl.org)