<div>On the tracker side, we need to think about making sure we limit "who" will answer. querying every tracker in the world and then them answering could be akin to a DDOS attack, eh?</div>
<div> </div>
<div>Maybe we need a range parm on the tracker to limit it's range to 100km by default from the query station? Of course it could/should be user adjustable, but default low.</div>
<div> </div>
<div>Wes<br><br></div>
<div class="gmail_quote">On Mon, Feb 9, 2009 at 2:44 PM, Scott Miller <span dir="ltr"><<a href="mailto:scott@opentrac.org">scott@opentrac.org</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="PADDING-LEFT: 1ex; MARGIN: 0px 0px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid">My new T2-301 trackers are frequency-agile and can measure incoming<br>signal strength, so it occurred to me that it'd be useful to define an<br>
APRS query that'd cause all capable stations to QSY their receive side<br>to the specified frequency for a second, take a reading, and then come<br>back and report what they heard in omni-DF format.<br><br>Before anyone asks, these particular units won't work for 121.5 - I've<br>
only been able to get them to receive as low as 127 MHz.<br><br>Based on some experimentation with a service monitor, it looks like the<br>usable RSSI range is roughly -128 dBm to -68 dBm. If I'm reading my<br>conversion chart right, for a 50-ohm system that's a little more than<br>
the standard S0-S9 range. Seems kind of low at the top end, but I'll<br>have to do some field testing and see what I get.<br><br>What I'm thinking of is something like this:<br><br>?DF146.520?<optional footprint><br>
<br>The response should be a DFSshgd omni-DF extension followed by the<br>frequency. I'd prefer the frequency to be a standard part of that<br>response, so clients could be made smart enough to separate out multiple<br>
DF plots.<br><br>Comments or suggestions?<br><br>Scott<br>N1VG<br><br><br>_______________________________________________<br>aprssig mailing list<br><a href="mailto:aprssig@tapr.org">aprssig@tapr.org</a><br><a href="https://www.tapr.org/cgi-bin/mailman/listinfo/aprssig" target="_blank">https://www.tapr.org/cgi-bin/mailman/listinfo/aprssig</a><br>
</blockquote></div><br><br clear="all"><br>-- <br>Wes<br>---<br>Where there's silence, there is no Hope.<br>