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ZL3AI > APRDIG 10.05.04 08:23l 260 Lines 10014 Bytes #999 (0) @ WW
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From: ZL3AI@ZL3VML.#80.NZL.OC
To : APRDIG@WW
Subject: Re: APRS Kenwood Radios
From: Jeff King <jeff@aerodata.net>
Date: Tue, 20 Apr 2004 15:30:17 -0400
X-Message-Number: 51
On Tue, 20 Apr 2004 12:46:25 -0500, David VanHorn wrote:
>>>How about making it possible for end users to install new
>>>firmware, or
>>even (gasp) open source?
>Unfortunately, they didn't design either radio with this in mind, so
>I'd guess we're stuck.
>
>I've been designing user-upgradeable software into products since
>'83.
I'm curious, why do you do this?
Is it because you respect your customers time, money and technical ability?
Because ultimately, your a good businessman?
Just curious.
-Jeff
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Subject: Re: [ui-view] Removal of the UI-View message extensions fromUI-View32
From: "Curt, WE7U" <archer@eskimo.com>
Date: Tue, 20 Apr 2004 12:35:30 -0700 (PDT)
X-Message-Number: 52
On Tue, 20 Apr 2004, John K9IJ wrote:
>>And relative positions of objects/items is an exception to this
>>rule. GPS is not required for this, therefore we don't have to
>>stick to GPS resolutions.
>
>Then what you're doing is NOT APRS . You maybe need to start your
>own SIG and take this kind of discussion there.
That's just... hilarious...
Ever read the spec?
--
Curt, WE7U archer at eskimo dot com
Arlington, WA, USA http://www.eskimo.com/~archer
"Lotto: A tax on people who are bad at math." -- unknown
"Windows: Microsoft's tax on computer illiterates." -- WE7U
"The world DOES revolve around me: I picked the coordinate system!"
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Subject: Re: APRS greater precision
From: "Curt, WE7U" <archer@eskimo.com>
Date: Tue, 20 Apr 2004 12:40:45 -0700 (PDT)
X-Message-Number: 53
On Mon, 19 Apr 2004, Jim Duncan wrote:
>Frankly, I'm surprised that some of the other developers haven't
>completely abandoned the APRS Spec and moved on in new directions
>already. If we truly want to encourage growth and expanded development
>it is definitely time to set a new course for this hobby.
Xastir has limited support for OpenTrac with more planned. I just couldn't
sit be and see what Scott was coming up with, without doing something to
get those packets onto a map display. I just had to help because it is all
just so... right!
--
Curt, WE7U archer at eskimo dot com
Arlington, WA, USA http://www.eskimo.com/~archer
"Lotto: A tax on people who are bad at math." -- unknown
"Windows: Microsoft's tax on computer illiterates." -- WE7U
"The world DOES revolve around me: I picked the coordinate system!"
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Subject: Re: [ui-view] Ambiguity?
From: "Robert Bruninga" <bruninga@usna.edu>
Date: Tue, 20 Apr 2004 15:43:34 -0400
X-Message-Number: 54
>>>"Curt, WE7U" <archer@eskimo.com> 4/20/04 12:10:55 PM >>>
On Sun, 18 Apr 2004, Robert Bruninga wrote:
Agree. But in once sense the Circle (or rectangle) implies TOO muck
knowledge. The purpose of the circle or rectangle is to SIGNAL the viewer
to not trust the symbol location. It was not intended as a specific
indicator of precise ambiguity...
Bob
In that interpretation then circle, square rectangle, anything does the
job... The above should be drawn as rectangles BTW, because that's what it
draws if you allow the unknown numbers to vary across all possible values.
We draw the above posits using rectangles to represent the unknown area for
that reason in Xastir.
Some of the other APRS clients draw them as circles, which is just plain
wrong. Work the numbers yourself.
--
Curt, WE7U archer at eskimo dot com
Arlington, WA, USA http://www.eskimo.com/~archer
"Lotto: A tax on people who are bad at math." -- unknown
"Windows: Microsoft's tax on computer illiterates." -- WE7U
"The world DOES revolve around me: I picked the coordinate system!"
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Subject: Re: [ui-view] Ambiguity?
From: "Robert Bruninga" <bruninga@usna.edu>
Date: Tue, 20 Apr 2004 15:45:58 -0400
X-Message-Number: 55
The use of a circle or rectangle or anything else to indicate an ambiguous
position was not intended to be a "precise" indication of "ambiguity". It
is only intended to "SIGNAL" the user not to trust the position below the
ambiguity indicated.
So using a square or a rectangel or a circle is OK with me. Trying to
claim it as a precise measur of ambiguity I find counterproductive and
missleading...
Bob
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Subject: Re: APRS Kenwood Radios
From: "Robert Bruninga" <bruninga@usna.edu>
Date: Tue, 20 Apr 2004 15:47:49 -0400
X-Message-Number: 56
Ah, so you only want to serve users that carry a Laptop for public
service... Then fine. But thats leaving out about 90% of what APRS can do
for the handheld user...
Bob
>>>"Scott Miller" <scott@opentrac.org> 4/20/04 12:21:08 PM >>>
>Duh, wrong planet you're on. Kenwood is holding nothing
>back. It is just a radio and a display. And it can display
>almost ALL of the APRS protocol. What is lacking is the
>creativity and initiative of HAMS to make use of it in
>imaginiative ways...
If I can assume total control of the display and user interface through the
serial port, and if it'll work as a KISS TNC, I'll buy one. But I'm not
going to try to work within the constraints of what it knows about APRS.
I'd rather move all of the protocol handling brains outside of the radio
and use the radio itself as a dumb front end.
As for firmware updates for ham hardware, anyone developing new stuff
should take a look at the OpenTracker's config interface. It's not
perfect, and it's not even really finished, but it's what I think people
should demand as a minimum for firmware upgrade support. You've got two
buttons to upgrade the firmware - one labelled 'file' and one 'web'. You
can click on the 'file' button and browse for a firmware file you've
already downloaded, or you can click 'web' and it'll connect to the
OpenTracker website and retrieve a descriptive list of all available
firmware files. Double clicking on one automatically downloads it to the
PC and then writes it to flash on the tracker.
The major deficiency at the moment is that the config program can't upgrade
itself. That'll be addressed in the future. If anyone would like
assistance implementing this sort of online firmware update, let me know
and I'll be happy to help.
Scott
N1VG
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Subject: Re: APRS greater precision
From: Henk de Groot <henk.de.groot@hetnet.nl>
Date: Tue, 20 Apr 2004 21:16:04 +0200
X-Message-Number: 57
At 17:28 19-4-2004 -0500, David VanHorn wrote:
>>
>>Next time, we need to make sure we get a spherical planet. This irregular
>>oblate spheroid thing just isn't cutting it.
>
>Cubes work..
Especially if you like to live on the edge...
Sorry, I couldn't resist...
Note that even in the proposal from Bob the ASCII doesn't have to be human
readable, both base 91 compressed data as MIC-E already dropped that
concept. So the only reason for using ASCII it to be able to run TNC's in
converse mode (instead of KISS).
If running TNC's in converse mode is so important, then maybe we need an
ASCII OpenTrack flavour. The idea is to just run the OpenTrack binary data
through UUencode and at the other end use UUdecode to make it binary again.
In other words a kind of tunneling binary data stream over a 7 bit ASCII
only channel, much like is done for sending attachments via e-mail (which
is also an ASCII medium). If a special prefix is used for encoded OpenTrack
data it can co-exist with APRS... Maybe that can provide a migration path
away from the Adhoc APRS protocol.
Kind regards,
Henk.
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Subject: Re: APRS greater precision
From: Henk de Groot <henk.de.groot@hetnet.nl>
Date: Tue, 20 Apr 2004 21:58:26 +0200
X-Message-Number: 58
At 18:43 20-4-2004 +0100, Laurie - g6isy wrote:
>This is due to the fact that there has been virtually no mapping data
>available
>to WGS84 (its nearly all OSGB36). I feel the addition of a datum identifier
The client software receives WGS84 data it so it has to convert it to
OSGB36 to be able to display it on the OSGB36 map. If you happen to have a
map in XYZ datum then the client should convert to XYZ. If it doesn't work
that way the client is broken (or it is limited to only handle only WGS94
maps).
How is the sender supposed to know what datum the map of the receiver has?
This breaks down as soon as you have 2 receivers using two maps with a
different datum. Ths only way to get is working is to transmit a globally
known well specified format and have the receiver deal with what ever is
needed to display the data correctly.
I always assumed that APRS required the use of WGS84 so an explicit datum
identification is not needed. It is sad to learn that this is not the case.
If there is no uniformity on what datum is transmitted then we make it much
more complex than it needs to be, the client will have to convert anyway
since there is no guarantee that the transmitted datum corresponds with the
datum of the map that happens to be loaded in the client.
If WGS84 would be required by APRS then a high precision is already present
today, just use the compressed format. The only reason why this doesn't
work is because people just send data with a random datum. So if there is
any need for an addition to the specification I would propose to make a
stronger requirement for WGS84 and describe that it is required that the
client is responsible for displaying it correctly. This is just like Bob's
propsal completly compatible with all existing implementations but also
much more sound (IMHO).
Kind regards,
Henk.
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