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NOTE Proceedings for conferences prior to the 25th are no longer available separately. However, see links below the ABSTRACTS for free PDF downloads. For details Read more ...
- Location:
- Santa Ana, CA
Read the conference story with audio and
photos.
Abstracts:
24th ARRL and TAPR Digital Communications Conference
September 23-25, 2005
- Open Source Software Licensing: Theory and
Practice
by John Ackermann N8UR - Abstract:
Open Source is the opposite of the proprietary model of software
development. As its name implies, Open Source software is developed
through an open process made
possible in large part by the Internet. It is shared, and licensed, in
source code form, and people
are free to modify it as they choose. It is normally, but not
invariably, made available to users at
no charge. Before talking more about Open Source, which is a development
philosophy, it.s important
to describe the idea of .Free Software. which is a political philosophy.
And that political philosophy
drives the license that lawyers love to argue about, the General Public
License . the .GPL., on which
most of this paper will focus.
- PIC-E Plus: Updating a Classic
by Gary Box N0JCG - Abstract:
This paper expands on the PIC-Encoder concept by porting the software
from the original project to
the recently released PIC 18F4550. The result is an expanded PIC-E with
more flash and RAM
memory, a USB interface, and enough horsepower to directly implement
software defined modem
functions.
- APRS-PSK63 For Improved Performance and Noise
Immunity on HF Radio
by Ken Chong WB6MLC and Bill Prats K6ACJ - HFPack/APRpack HF Portable Group - Abstract:
APRS (Automatic Packet/Positioning Reporting System) developed by Bob
Bruninga, WB4APR,
has become extremely popular worldwide. Over the years there has been
tremendous growth in
VHF digipeating, the APRS Internet Network, and recently UHF 9600 bps
experimental nodes are
making a comeback. HF APRS hasn.t changed much since the 90.s with Bell
102 tones still in use. At
last, a simple way was found to link WinAPRS with a resurrected PSK31
TCP/IP Server upgraded for
double speed. APRS-PSK63 (including QPSK63) is now possible with
WinAPRS, as well as
UIVIEW. Readers of this article will be able to setup their own
APRS-PSK63 HF nodes. On-the-air
trials have been very promising with improved performance and noise
immunity!
- Digital Mode CCW
by Patrick Lindecker F6CTE - Abstract:
In this paper, I will describe the digital mode "CCW" ("Coherent CW"
Morse keying).
Newcomers not required to copy CW as part of their test could find an
initiation
to CW and "old CW hands" could find interest in this mode."
This mode is available in the Multipsk "freeware" program, downloadable
from the
following WEB site: http: //members.aol.com/f6cte/
- Digital SSTV: General Objectives of the Compression
and Picture Transmission Protocol "Run" - Version 1
by Patrick Lindecker F6CTE - Abstract:
In this paper, I describe a digital picture transmission protocol named
.Run.
which has the main originalities, in one hand, to be able to be included
in a text
and, in the other hand, to be able to be decoded at any moment when the
transmission is in progress. The transmission modes supporting, at
present,
this protocol are Packet (300 and 1200 bauds), PSK63F and PSK220F.
The software abling this functionality is called .Multipsk., it is
downloadable
from the author WEB site: http://members.aol.com/f6cte/
At the end of this paper, are presented some snapshots of the program.
- Eliminating Digipeater (Source) Routing from
AX.25
by Peter Loveall, AESPL - Abstract:
Evolving AX-25 consensus opinion is that repeater chaining belongs to a
higher protocol layer. Consequently, it is
being phased out of Layer 2, although backward compatibility is being
maintained with a limit of two
repeaters. Note that it was the original intent and continues to be the
intent to eliminate repeater chaining from the link
layer. I published the first version of the No-Source-Route (NSR)
algorithm for UI digipeaters in the Winter 2005 PSR.
- A Spread-Spectrum Mode for HF
by Antonino Porcino IZ8BLY - Abstract:
A new HF-oriented digital mode which exploits the possibilities offered
by Spread Spectrum
modulations is presented. This new mode, called .Chip64., tries to solve
the compromise between low
baudrates and phase instability of traditional narrow band modes by
implementing a Direct Sequence
Spread Spectrum architecture. This implementation of Spread Spectrum has
been downsized to fit the
limits of HF channels. Real experimentation with this new mode is
possible with a software for PC and
soundcard developed by the author and freely distributed.
- Visualizing APRS Messaging with HEML
by Dr. Bruce Robertson VE9QRP and Kevin Green - Mount Allison University, Canada - Abstract:
This paper describes a webaccessible computer program which generates
timelines and animated maps from APRS messaging data extracted from the
APRSworld database.
- The KF6XA to W3NRG 10 Meter PropNET Experiment,
Comparison of Summer Versus Winter Profiles, Six Meter Path also
Confirmed
by Ed Sack W3NRG - Tucson Amateur Packet Radio Corporation - Abstract:
As an active member of the PropNET system, W3NRG has recorded thousands
of ten meter
transmissions from fellow PropNET participant, KF6XA over the past four
years. What makes these
measurements interesting is that the path between the stations would not
usually be considered
"consistently viable" for 10-meter communications. A model for the
transmission path has been
proposed and winter and summer reception profiles compared. Recently,
KF6XA and W3NRG have
been able to show that the path is also viable on 6 meters, in
verification of World War II research in
the same area.
- Google Earth, Applications for Ham Radio
by Darryl Smith VK2TDS - Abstract:
Applications for maps and mapping software have increased exponentially
in the last few years. With the increased availability of wireless data
links
and cheap GPS receivers have come applications that could only be
dreamed of a decade ago. To support this infrastructure, Google have
released a digital terrain model of the earth with superimposed aerial
photographs with an open interface for adding all sorts of information
on
top of this model. This paper looks at the Google Earth product and some
applications to Ham Radio.
- Integrated Map Data for Real Time Use
by Mark Sproul KB2ICI - Abstract:
APRS has been around for over 10 years; there are many versions of
software that
support the on-air protocol. The primary difference between the various
programs besides
user interface style is the mapping. Map detail and map information is a
very important
part of the APRS environment. Early on, computer capabilities were the
limiting factor
for good maps. Data was available, but it was very large and the
computers did not have
the memory or the speed to deal with it directly. Therefore short cuts
had to be taken.
Now the speed and memory of even today.s laptops can handle very large
amounts of
data, download it in near real time and display very detailed
information.
With the speed and capacity of current desktop and laptop computers, not
only
can we handle very detailed maps, but we can simultaneously display data
from multiple
sources such as roads, elevation, and imagery, all integrated
seamlessly.
- Software Defined Radios for VHF Through SHF
by Gerald Youngblood, K5SDR - FlexRadio Systems - Abstract:
The FlexRadio Systems. SDR-1000 is the first commercially available
Software Defined
Radio (SDR) transceiver for the amateur radio market. The SDR-1000 began
shipping in
April of 2003 with GPL open source software, a first for a commercial
transceiver. This
has created a groundswell of support for the radio from contributors
worldwide. This is
evidenced by the constant improvement available through free software
downloads on
almost a weekly basis. These enhancements are well documented in the
October 2005
QST product review, .FlexRadio Systems SDR-1000 HF+VHF Software Defined
Radio
Redux.. The current SDR-1000 now boasts dynamic range performance that
meets or
exceeds that of radios costing ten times its cost.
