Observations of the
codec used for D-Star - How does the codec used for
D-Star respond if subjected to sounds other than those of the
human voice? We decided to find out.
D-Star repeater
installation - Experiences, problems encountered
with the installation of a D-Star Stack at a very busy
radio site - and solutions to these problems.
The following are FAQ's provided by the Utah VHF
society. Note that these may topically overlap the links
above:
NU5D's "Discriminator audio" and
"RSSI" modifications - If you plan to put up a
repeater, it is strongly recommended that you
read this page and make the suggested modifications. If
you need to do any RF troubleshooting on the
repeater - such as determine sensitivity, find out if there is
enterference, or even just make sure things are working properly
- it is recommended that you check this page out! The original link no longer works
so this is a locally-archived copy.
http://home.roadrunner.com/~mdmiller7/images/dv/ch_sp/Dstar_Co.pdf
- Measurements of co-channel interference: Mark,
N5RFX, has conducted Adjacent/Co-Channel testing similar to
those done by the Utah VHF Society mentioned above: Note
that the equipment used, methodology, and the thresholds for
various aspects of these tests are slightly different from
those described on the Utah VHF Society page above, yielding
slightly different results: The reader must take
these differences into account before attempting to draw
direct comparisons between these two sets of results.
A
Look Inside D-Star Modulation - An article (in .PDF)
from the Winter, 2009 CQ VHF Magazine about D-Star by Bob Witte,
K0NR.
A Discussion
about Michigan Repeaters and D-Star - This article
discusses the co-habitation of D-Star and analog repeaters,
D-Star channel spacing, and a few other practical implications
of the integration of D-Star repeaters on the 2-meter band.
Radio
problems
during a fatal fire. This page contains a
sobering example of a tragedy that can, in part, be attributed
to shortcomings of the communications system may be found here
and includes audio files and some brief analysis of what
happened. Linked
from Daryl Jones' blog.As with any
blog, please use your judgment to weigh possible bias of the
author and its effects of the facts.
Please note that some of the problems associated with digital,
trunked systems do not necessarily apply to amateur radio
implementations of digital voice technology. It is,
however, well-worth the time for a designer of a radio network -
amateur or professional - to become familiar with these systems
and take advantage of lessons learned by others, applying them
to system design, and to the training of those who are destined
to use it!
The above lists are, by no means, exhaustive: Other
information may be found via web searches.
Questions, updates, or comments pertaining to this web page
may be directed to the frequency
coordinator.