<div>All this talk of using cell phones and infrastructure.....</div><div><br></div>It's funny.... a concept which is so simple to us... a multicast beacon message.... is so far out of the realm of cell phone users... They can grasp SMS messages. But they are so accustomed to directed messages, the whole "cellular broadcast" thing was quite difficult to explain to my office mate. The idea that you can send ONE message from the tower and it will show up on 1000 cell phones all at the same time!! Imagine! Questions like "do I have to sign up?" "how does it know I'm in the area if I'm away from my home area?" sheesh.... <div>
<br clear="all">Wes
<div>---<br>The world needs more geniuses with humility because there are so few of us left.<br></div><br>
<br><br><div class="gmail_quote">On Tue, May 24, 2011 at 14:32, Stephen H. Smith <span dir="ltr"><<a href="mailto:wa8lmf2@aol.com">wa8lmf2@aol.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<div class="im">On 5/24/2011 9:37 AM, Julian, G4ILO wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
I understand and agree with you Gregg but as a user of Lynn KJ4ERJ's<br>
APRSISCE in Windows Mobile and also an owner of several APRS RF<br>
devices I find myself in something of a dilemma. Do I use APRS over<br>
cellular and get all these improved features or do I stick true to the<br>
spirit of the hobby, use the radio and accept the limitations of the<br>
radio devices and the bandwidth?<br>
</blockquote>
<br></div>
The smart phone types seem to also forget that cellular "wireless" depends on VAST amounts of infrastructure - you must be within 5 miles or so of a cell site, for all these neat gadgets with their fractional-watt transmitters linked to low-performing hidden antennas to work. (It seems to be impossible now to get a cell phone with an actual exposed whip antenna or external antenna connector. )<br>
<br>
Our clunky old low-bit-rate narrowband radios transmit 10s of watts (or more) into real antennas, results in vastly more robust long-distance communications.<br>
<br>
<br>
I recently attended a seminar on conventional land mobile radio vs broadband "4G" LTE for public safety comms. An interesting take on the differences I had never heard brought up before was contrasting the energy density per Hz of bandwidth (which ultimately determines the SNR at the receiver and data throughput achievable). 35 watts in a 20 KHz bandwidth for FM LMR vs a one-third-watt smeared out across 10 megahertz.for LTE. The implication was that for comparable coverage area for the user in a large metro police dept or county sheriff's dept, you would require 10-20 times (!) the number of base station sites for LTE broadband; i.e. they would basically be building another cellular network.<div class="im">
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<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
APRS over cellular is as much ham<br>
radio as Echolink on a computer (or cellphone) and I think many of us<br>
would be quite scathing of someone who claimed he made a ham radio<br>
contact because he called someone up on Echolink.<br>
<br>
</blockquote>
<br></div>
A lot of people seem to forget that the original intent of EchoLink was to interconnect RADIOs in different regions together over the Internet.<br>
<br>
Several years ago, I saw a posting somwhere reporting that the author of EchoLink now regretted implementing the local-user-in front-of-PC-mike-&-speaker mode of EchoLink rather than keeping it strictly a radio-to-radio setup like IRLP. Providing the local user mode reduced EchoLink to being essentially a hams-only version of Skype or Google Voice.<br>
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--<br>
<br>
Stephen H. Smith wa8lmf (at) <a href="http://aol.com" target="_blank">aol.com</a><br>
EchoLink Node: WA8LMF or 14400 [Think bottom of the 2M band]<br>
Skype: WA8LMF<br>
Home Page: <a href="http://wa8lmf.net" target="_blank">http://wa8lmf.net</a><br>
<br>
===== Vista & Win7 Install Issues for UI-View and Precision Mapping =====<br>
<a href="http://wa8lmf.net/aprs/UIview_Notes.htm#VistaWin7" target="_blank">http://wa8lmf.net/aprs/UIview_Notes.htm#VistaWin7</a><br>
<br>
*** HF APRS over PSK63 ***<br>
<a href="http://wa8lmf.net/APRS_PSK63/index.htm" target="_blank">http://wa8lmf.net/APRS_PSK63/index.htm</a><br>
<br>
"APRS 101" Explanation of APRS Path Selection & Digipeating<br>
<a href="http://wa8lmf.net/DigiPaths" target="_blank">http://wa8lmf.net/DigiPaths</a><div><div></div><div class="h5"><br>
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