[Xastir] System cost options

[Tom Russo]

On Wed, Jun 27, 2007 at 09:01:50AM -0700, we recorded a bogon-computron collision of the <archer at eskimo.com> flavor, containing:
> On Wed, 27 Jun 2007, Tom Russo wrote:
> 
> > We don't disagree that much.
> 
> Give me time...
> 
> 
> > I am very distrustful of these ultra-low-power, deaf trackers.
> >
> > But there are many of them getting made, so *somebody* must be finding them
> > useful.  To be useful, the APRS infrastructure must be very good, the terrain
> > must be wide open, and the loading of the infrastructure must be low.  I
> > hinted at that with my first paragraph.
> 
> I have used low-powered deaf trackers, and have friends who have, in
> the form of the PocketTracker.  This one puts out 270mW at best, and
> fits in an Altoids tin with a 9V battery.  Hook up a GPS to it with
> a cable and you're up and running.  Most people run them with a
> walkie-talkie rubber duck antenna (not the most efficient type
> antenna by any means).
> 
> I've had basically no luck getting into the system with this device
> over my normal commute route, even when hooked to my 1/4 wave whip
> antenna on the roof.  Another friend was living in northern CA for a
> bit and tried running one in a similar manner with a whip antenna
> and didn't get in either.
> 
> To be fair, I'm in the fringe area of one of the busiest APRS areas
> (Puget Sound/Seattle), and travel mostly in a county with no
> digipeaters of it's own plus lots of hills/canyons/mountains.  There
> are digi's within range if I don't have a lot of dirt between me and
> the hilltops, but only if you're running enough power to compete
> reasonably with everyone else who's trying to get positions in.

None of that is inconsistent with what I said.  You're in an area with
a great infrastructure, but terrain and network loading that makes 300mW
trackers useless.  I'd expect California to be as bad or worse.  Even here
in New Mexico it would be hard to use them even with our good infrastructure
and relatively light loading (because of terrain).

I recommend real trackers with power and antennas, too.  And I continue to
recommend the turn-key D7 solely for the ease with which an organization
can deploy them in largish numbers.  I like kit solutions, but in my experience
unless one person is going to do the build out, or a large pool of highly
motivated and skilled people are going to build them to a standard, and 
quickly, kits are not a good way to go for a rapid deployment of capability.  

The original poster was uninterested in kit solutions, so Tracker2 and TinyTrak
solutions aren't really an option.  One could buy assembled and tested
units of TinyTrak or OpenTracker units and build them into an APRS tracker,
but that's still significant effort with lots of room for "learning experiences"
along the way.  Tracker2 is not available at the moment --- it's still in 
beta testing, and when a new batch of beta boards comes out they're snapped
up in a couple of days.  Not what the original poster wanted at all.

The best solution to the problem posed by the original poster is a bunch of 
APRS appliances like D7's.  As corners need to be cut to fit available funding,
one has to explore options.  The low power units like the MicroTrak should
be at the very bottom of the list of options.

-- 
Tom Russo    KM5VY   SAR502   DM64ux          http://www.swcp.com/~russo/
Tijeras, NM  QRPL#1592 K2#398  SOC#236 AHTB#1 http://kevan.org/brain.cgi?DDTNM
"And, isn't sanity really just a one-trick pony anyway? I mean all you get is
 one trick, rational thinking, but when you're good and crazy, oooh, oooh,
 oooh, the sky is the limit!"  --- The Tick