| |
ZL3AI > APRDIG 10.05.04 09:02l 269 Lines 9836 Bytes #999 (0) @ WW
BID : 3184-ZL3AI
Read: GUEST
Subj: TAPR Digest, Apr 20, 13/17
Path: DB0FHN<DB0FOR<DB0SIF<DB0EA<DB0RES<ON0AR<GB7FCR<GB7WIG<GB7ESX<ZL2BAU<
ZL3VML
Sent: 040510/0647Z @:ZL3VML.#80.NZL.OC #:23702 [Chch-NZ] FBB7.00i $:3184-ZL3AI
From: ZL3AI@ZL3VML.#80.NZL.OC
To : APRDIG@WW
Subject: Re: [ui-view] Ambiguity?
From: "Robert Bruninga" <bruninga@usna.edu>
Date: Tue, 20 Apr 2004 17:31:31 -0400
X-Message-Number: 73
>>>"Curt, WE7U" <archer@eskimo.com> 4/20/04 5:27:04 PM >>>
On Tue, 20 Apr 2004, Robert Bruninga wrote:
>Well, you'd _think_ so, but in reality you're just chopping off
>significant digits from a lat/long location, so the net result is
>that you are somewhere within the described rectangle.
No you are missinterpreting ambiguity. It has nothing to do with CHOPPING
of digits. Ambiguity uses a SPECIAL character (a SPACE) to indicate
whether one, two, three or 4 digits of ambiguity are intended by the
sender.
It means no more and no less... It does not chop off digits. It is a
SIGNAL in the protocol of the degree of ambiguity associated with that
position. If code is interpreting it as chopped off digits, then the
author better re think the implementatin.
Bob
----------------------------------------------------------------------
Subject: Re: [ui-view] Ambiguity?
From: "Robert Bruninga" <bruninga@usna.edu>
Date: Tue, 20 Apr 2004 17:33:32 -0400
X-Message-Number: 74
That IS what ambiguity IS!!!!!!!
It is NOT chopped off digits!
It is using the SPACE character to communicate the degree of ambiguity. It
just conveniently conserves BYTES and bandwidth by inserting that space
"signal" in the otherwise UNUSED digits....
Bob
>>>"Curt, WE7U" <archer@eskimo.com> 4/20/04 5:30:10 PM >>>
On Tue, 20 Apr 2004, Robert Bruninga wrote:
>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
>Ifind counterproductive and missleading...
I see chopping off significant digits from a position as a way to represent
position ambiguity to be misleading.
What we need instead is a normal position report plus a new parameter which
specifies the ambiguity. That makes more sense mathematically, as it can
them be represented as a circle around the position.
--
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!"
----------------------------------------------------------------------
Subject: Re: APRS Kenwood Radios
From: "Robert Bruninga" <bruninga@usna.edu>
Date: Tue, 20 Apr 2004 17:37:38 -0400
X-Message-Number: 75
There is no problem. Takes only a line of code. In the existing position
comment protocol you only need to look for two things now:
/A= is a tag of altitude
[xx] is the numeric value to put on
a SIGN post icon
!xyz! for the new 2 foot precision...
It is trivial to write code to look for the "/, [, and !" characters... I
hope I didnt leave any out... Bob
>>>"Scott Miller" <scott@opentrac.org> 4/20/04 5:31:26 PM >>>
By a tagged format, I mean look at all the other bits of information we
keep wanting to squeeze into the comment field and extensions, and figure
out a consistent way to put it all in there so it's easy and unambiguous to
parse. You ought to be able to express the whole thing in BNF notation so
there's no question of which part means what.
Scott
N1VG
----------------------------------------------------------------------
Subject: Re: APRS greater precision
From: "Scott Miller" <scott@opentrac.org>
Date: Tue, 20 Apr 2004 14:37:50 -0700
X-Message-Number: 76
>It's funny, most people think we're out there looking for the lost
>subjects... In reality we're supposed to be looking for clues to
>the lost subjects, as those are more plentiful. Marking where the
>clues and other objects of interest are on the map is important, as
>you can do statistics based on lost subject behavior, and you can
>see trends in the clues. That's why we need higher resolution than
>DDMM.MM provides for SAR.
Good point. I got to practice plotting the location of a peanut shell on a
1:24000 topo by hand last weekend. I *really* want to put together a
tracker that'll give field teams four color-coded flagging buttons that they
can it when they find something, and have it store those waypoints locally
until it's sure they've been received at the command post.
Scott
N1VG
----------------------------------------------------------------------
Subject: Re: APRS Kenwood Radios
From: "Scott Miller" <scott@opentrac.org>
Date: Tue, 20 Apr 2004 14:46:56 -0700
X-Message-Number: 77
And for telemetry values, IRLP status, message ack... ? PHG and DF bearing
in the same message? What was it we were discussing overloading the N and S
values for a while back?
Scott
N1VG
----- Original Message -----
From: "Robert Bruninga" <bruninga@usna.edu>
To: <aprssig@lists.tapr.org>; <scott@opentrac.org>
Sent: Tuesday, April 20, 2004 2:37 PM
Subject: Re: [aprssig] Re: APRS Kenwood Radios
>There is no problem. Takes only a line of code.
>In the existing position comment protocol you only
>need to look for two things now:
>
>/A= is a tag of altitude
>[xx] is the numeric value to put on
> a SIGN post icon
>!xyz! for the new 2 foot precision...
>
>It is trivial to write code to look for the "/, [, and !"
>characters... I hope I didnt leave any out... Bob
----------------------------------------------------------------------
Subject: Re: Lynching plans...
From: Jeff King <jeff@aerodata.net>
Date: Tue, 20 Apr 2004 18:02:21 -0400
X-Message-Number: 78
On Tue, 20 Apr 2004 17:12:57 -0400, Steve Dimse wrote:
>I do think that it is wrong to refer to any project as "APRS 2.0" as
>I have heard some people do. APRS is a registered trademark owned by
>Bob, and that legal right must be respected by everyone.
That might have been me. I was just going off the APRS-WG documents dated
from 1999 and 2000 (you where a member then?) in which it was stated
extensions to the APRS spec would be accepted after 1.0 was ratified, which
it was in 2000. Being it is now 4 years later, I didn't think I was out of
line suggesting this.
Since Bob had stated he was encourage folks not to use the compressed BASE91
postion report, I had suggesting it be replaced with OpenTrack reports in the
spec. Worst case, as you allude to, nothing would happen with it.
Then again, it is fairly clear to me where we stand (and I think you are
suggesting it as well), so your point is well taken.
----------------------------------------------------------------------
Subject: Re: Kenwood MObile APRS
From: "Curt, WE7U" <archer@eskimo.com>
Date: Tue, 20 Apr 2004 15:10:24 -0700 (PDT)
X-Message-Number: 79
On Tue, 20 Apr 2004, Robert Bruninga wrote:
>Who is "we". If basement video game players want to
>run off and play with trinkets, then go ahead.
Where'd THAT come from???
>But of the
>23,000 stations you listed, 11,000 of them are digis or
>other fixed assetts, 6100 of them were home stations
>most of them doing nothing...
Define "doing nothing". I believe my home system does a lot for me.
>of the remaining 6400,,
>then 4600 of them (70% of all mobiles) were Kenwood or
>Mic-E's ACTUALLY OUT DOING SOMETHING.
>
>I dont think that your desire to obsolete the 70% of
>all APRS mobile operators who are actually USING
>APRS for something besides weather will appreciate
>your desire to obsolete them.
And where'd THAT come from? "something besides weather" and "actually
using APRS for something". Interesting. Did I say I wanted to obsolete
anything at all? No, I said I wanted to grow APRS and/or OpenTrac. There's
a big difference.
Did you noticed that Xastir users are higher than APRSdos users these days?
We must be doing SOMETHING with it, even if it's just playing video games,
as you suggest.
Sorry you're pissed Bob. I don't think I was the direct cause of it. I'm
just discussing issues. I don't have any idea what direction you're headed
now with the discussion.
>Remember,. APRS was not designed to b e a toy like
>a video game for people with an attention span of a few
>minutes...
Who brought that up?
I use it for SAR work. I use it for mapping while driving. I use it for a
lot of things, but perhaps not what you intended originally. So what?
>It was desiged to be a real-time-in-the field means
>to exchange digital info... to the end user.... who would
>actually use it for something. After practicing and learning
>how to use it.
You mean like SAR work?
>P.S. Yes, some of the PC's listed above could have been
>mobile, but what I see, it is less than 5% of the number of
>mobiles have any kind of PC or display other than the
>Kenwoods.
And your point is? Just because a laptop is more of a hassle in terms of
space, wiring, power, etc, doesn't mean it isn't useful. In my case I use a
truck-mount touch-screen PC running Linux/Xastir.
Most people would choose simpler over more complicated, but in my case I
wasn't interested in the Kenwoods. I see why most people would choose the
all-in-one unit. The cost initially drove me away, and the inflexibility
is keeping me away. I'm not attacking them, I'm just not personally
interested in having one. I can't grow and experiment with a
fixed-firmware unit.
--
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!"
----------------------------------------------------------------------
Read previous mail | Read next mail
| |
