<html>
<head>
<meta content="text/html; charset=ISO-8859-1"
http-equiv="Content-Type">
</head>
<body text="#000000" bgcolor="#FFFFFF">
Hi Bob,<br>
<br>
That would be easily done on the TH-D72a. (Do you mean that a
single packet goes out with WIDE2-1,WIDE2-2 , or were you giving me
settings for different transmissions in the proportional ring?)<br>
<br>
The VX-8GR does not support proportional pathing. I am thinking
that I should set it to either WIDE1-1 or WIDE2-1 and just leave it
like that. It seems it would be likely to provide good enough
coverage most of the time (I think it would be rare where one
station has a good copy on one digi, and the other on a different).<br>
<br>
Thanks for the tips.<br>
<br>
-- John<br>
<br>
On 04/30/2012 05:47 PM, Bob Bruninga wrote:
<blockquote cite="mid:011401cd2723$392ea7f0$ab8bf7d0$@edu"
type="cite">
<meta http-equiv="Content-Type" content="text/html;
charset=ISO-8859-1">
<meta name="Generator" content="Microsoft Word 12 (filtered
medium)">
<style><!--
/* Font Definitions */
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:Tahoma;
panose-1:2 11 6 4 3 5 4 4 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman","serif";
color:black;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
span.EmailStyle17
{mso-style-type:personal-reply;
font-family:"Calibri","sans-serif";
color:#1F497D;}
.MsoChpDefault
{mso-style-type:export-only;
font-size:10.0pt;}
@page WordSection1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
{page:WordSection1;}
/* List Definitions */
@list l0
{mso-list-id:187642052;
mso-list-template-ids:-150575422;}
@list l1
{mso-list-id:555749101;
mso-list-template-ids:-1292588312;}
ol
{margin-bottom:0in;}
ul
{margin-bottom:0in;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
<div class="WordSection1">
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Simple
answer!<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Proportional
pathing for the caravan with WIDE2-1,WIDE2-2 path. Everyone
hears everyone else at a one minute rate for up-to-date live
situational awareness but most of your packets are direct
and do not bother anyone in the area. Half of your packets
may make it to a local digi, but only 1/4<sup>th</sup> will
bother the surrounding area. Same goes for hiking.<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Bob,
WB4APR<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<div>
<div style="border:none;border-top:solid #B5C4DF
1.0pt;padding:3.0pt 0in 0in 0in">
<p class="MsoNormal"><b><span
style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext">From:</span></b><span
style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext">
<a class="moz-txt-link-abbreviated" href="mailto:aprssig-bounces@tapr.org">aprssig-bounces@tapr.org</a>
[<a class="moz-txt-link-freetext" href="mailto:aprssig-bounces@tapr.org">mailto:aprssig-bounces@tapr.org</a>] <b>On Behalf Of </b>John
Goerzen<br>
<b>Sent:</b> Monday, April 30, 2012 5:41 PM<br>
<b>To:</b> TAPR APRS Mailing List<br>
<b>Subject:</b> [aprssig] Group tracking<o:p></o:p></span></p>
</div>
</div>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Hi folks,<br>
<br>
I'd like to get some recommendations on beacon configuration
for group tracking scenarios. The main scenarios I have in
mind are:<o:p></o:p></p>
<ol start="1" type="1">
<li class="MsoNormal"
style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l1
level1 lfo1">A caravan of 2 or 3 vehicles traveling to a
common destination. The trip could be 30 minutes or 15
hours, could involve a mix of highway speeds (75 MPH) and
city speeds (20 MPH or less). The point of APRS tracking
would be to give at least one vehicle the means to find the
other if needed, due to getting separated in traffic, taking
different exits, loss of cellphone communication, etc. The
vehicles will usually, but conceivably not always, be within
simplex range of each other (owing to lack of external
antennas and high speeds in some cases).<o:p></o:p></li>
<li class="MsoNormal"
style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l1
level1 lfo1">Hikers in 2 groups in a large park/wilderness
area. A similar goal as before - give at least one group
the means to find the other assuming nothing but APRS
beacons as communication. Here I would assume that the
hikers will be within simplex range (say, a mile or two) of
each other at 5W.<o:p></o:p></li>
</ol>
<p class="MsoNormal">One could also add other similar scenarios,
such as coordinating search and rescue parties, tracking
SKYWARN volunteers, etc.<br>
<br>
There are a few special things about these scenarios:<o:p></o:p></p>
<ol start="1" type="1">
<li class="MsoNormal"
style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l0
level1 lfo2">We may not usually care about getting frequent
position updates. During the minutes / hours in which one
party is not trying to locate the other, we don't care too
much about getting frequent updates.<o:p></o:p></li>
<li class="MsoNormal"
style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l0
level1 lfo2">When one group is trying to locate the other,
default position update timings will likely be way too
long. For instance, 5 minutes or even 2 minutes at 70MPH is
a lot of miles and a lot of potential exits that may or may
not have been taken. A lot of SmartBeaconing scenarios have
30 minutes between beacons at 20MPH, which is unreasonable
for tracking someone in city traffic. (And, according to my
reading, could actually be even longer at speeds between the
low and high speed, oddly enough)<o:p></o:p></li>
</ol>
<p class="MsoNormal">One could conceivably use a TinyTrak AIO or
similar device for the group being tracked, though in my
particular case it will likely be a locked VX-8GR. Neither
the TinyTrak nor the 8GR responds to APRS position query
packets (?APRSP), so that is out. The TH-D72A does, but it is
also larger and for various reasons is also the stronger
tracker device.<br>
<br>
For the hiking scenario, we could conceivably use a 440
frequency since it is unlikely that a digipeater would be of
any help at all. This puts less of an importance on
restricting transmit rates. A lot of testing suggests that
battery drain on APRS HTs is usually due to engaging the RX
side, not the TX side, so I would not have battery concerns on
a simple 1-minute interval.<br>
<br>
For the car travel, we would probably want to use WIDE1-1 (are
there any digis that would answer to WIDE2-1 but not WIDE1-1?)
to get a little help from nearby digis, due to the likelihood
of greater separation and more challenges to RF signals
getting out. It seems a bit annoying to have a 1-minute
beacon going from a restaurant parking lot for an hour on
144.390, but perhaps it is not as bad as I am making it out to
be. It seems that if I set the low speed on SmartBeaconing
to, say, 5MPH to prevent this, and set the high rate to 2
minutes and the low rate to 5 minutes, it would lead to some
very long intervals at, say 10MPH (70/10*2 is 14 minutes). An
odd little gap in the SmartBeaconing design, that.<br>
<br>
What are suggestions to both meet the objectives and be
friendly to other RF users?<br>
<br>
Thanks,<br>
<br>
John<br>
KR0L<o:p></o:p></p>
</div>
<br>
<fieldset class="mimeAttachmentHeader"></fieldset>
<br>
<pre wrap="">_______________________________________________
aprssig mailing list
<a class="moz-txt-link-abbreviated" href="mailto:aprssig@tapr.org">aprssig@tapr.org</a>
<a class="moz-txt-link-freetext" href="https://www.tapr.org/cgi-bin/mailman/listinfo/aprssig">https://www.tapr.org/cgi-bin/mailman/listinfo/aprssig</a>
</pre>
</blockquote>
<br>
</body>
</html>