| |
ZL3AI > APRDIG 08.05.04 23:04l 206 Lines 9396 Bytes #999 (0) @ WW
BID : 3168-ZL3AI
Read: GUEST
Subj: TAPR Digest, Apr 18, 2/4
Path: DB0FHN<DB0RGB<DB0AAB<DB0FSG<DB0PV<DB0MRW<OK0PKL<OK0PPL<DB0RES<ON0AR<
WB0TAX<KB2TXP<ZL2BAU<ZL3VML
Sent: 040508/1921Z @:ZL3VML.#80.NZL.OC #:23600 [Chch-NZ] FBB7.00i $:3168-ZL3AI
From: ZL3AI@ZL3VML.#80.NZL.OC
To : APRDIG@WW
Subject: Re: Official Baker to Vegas 2004 Tracking Website Complete
From: "Phil Pacier, AD6NH" <ad6nh@arrl.net>
Date: Sun, 18 Apr 2004 10:52:37
X-Message-Number: 9
Great points, all of them. Just a couple of quick comments:
On 04/18/04, "Steve Dimse <k4hg@tapr.org>" wrote:
>>The only
>>thing I have not quite figured out yet is the mileage table.
>
>By knowing where the checkpoints are, findU can place a team on the correct=
> leg,
>and estimate the distances between team and the two checkpoints, it is linear
>between the checkpoints, so it does not take into account the twists of the
>mountain road (my requests for a more complete set of points, as I used for
> the
>Mississippi River Challenge, have not been answered), it is not perfect, butis
>can at a glance show where all the teams are.
Are you saying that it is possible to create a mileage chart that takes
into account the actual road miles? Creating a linear distance chart is
almost easy, but far from accurate, particularly on this course. I guess
you would need a database that had waypoints marked at each curve? Time
consuming, but quite possible for next year. I would love to have some
sort of mileage chart on the official site.
>>The official
>>site also uses full-color street-level scale maps.
>
>Actually the use of tigermaps would be of concern to me, especially if you
>get
>big loads. The tiger server can take 15 seconds or more during peak periods
> to
>produce a map. The event occurs on weekends, so there will probably be light
>loading outside of your application, hopefully you will be OK.
The goal is to have the Tiger maps as temporary for now. I am working on
creating my own maps for the race. It may not happen this year, but I'm
going to give it a shot. I don't want to just cut and paste quick maps and
have it look like a patchwork job. I understand the problem/uncertaintly
with using a public mapserver! I'd love to run one local for the page - I
have the computing power and hard drive space.
>As to street level maps, one of the things I've come to realize is that Bob
> is
>right about simplier maps being better for APRS (at least for some uses). The
>purpose of an APRS map is to provide context for position reports. In this
>particular case, the context is the course and the checkpoints. In my opinion,
>anything more distracts people from the essential information.
The reason I have gone to more detail maps is a result of conversations I
have had with viewers and the race committee who wanted to see something a
little more detailed than the DOS maps. Some will use that map as a
reference point for going out to the course, and will want the landmarks
and such to show up. I agree that simpler maps are a better choice in many
situations.
>No matter how you watch, this is one of the best APRS events of
>the year, everyone should take a look, it is very cool, my congrats to the
>guys that pull this off so well every year!
And it keeps growing! With the price of equipment dropping, we are able to
get more teams involved in tracking this year. We hope to have 50 of the
220 teams trackable this year. Doesn't sound like a great percentage, but
it is a great improvement each year. Enjoy the race!
PS to Steve - I'll get you an updated team key before I leave for the race.
The one you have grabbed has some flaws in it. I hadn't forgotten to send
it to you - just waiting for it to be finalized.
73
Phil - AD6NH
http://b2v.aprsca.net
----------------------------------------------------------------------
Subject: Re: Official Baker to Vegas 2004 Tracking Website Complete
From: Steve Dimse <k4hg@tapr.org>
Date: Sun, 18 Apr 2004 12:23:13 -0400
X-Message-Number: 10
On 4/18/04 at 10:52 AM Phil Pacier, AD6NH <ad6nh@arrl.net> sent:
>Are you saying that it is possible to create a mileage chart that takes
>into account the actual road miles? Creating a linear distance chart is
>almost easy, but far from accurate, particularly on this course. I guess
>you would need a database that had waypoints marked at each curve? Time
>consuming, but quite possible for next year. I would love to have some
>sort of mileage chart on the official site.
Yes, it is easy if you have a set of points. For example, a year or so ago
there was a successful attempt to break the canoe record for traveling the
Mississippi river. For that, they gave me a lat/lon for every mile on the
river, which came from the Corps of Engineers. With that, it was easy to
turn a lat/lon into a mile mark. Again, for this, it was not perfect, as
the interpolation between points must be linear, but the error would always
be less than a quarter mile. From this I calculated average speed, time
remaining at average speed, and how much they would break the record by. I
also had a set of 40 points from the old record holder, so I could directly
compare the two attempts, actually plotting the old position on the maps,
though that was not too useful after a couple days as they shattered the
old record...
All you need for greater accuracy is more points, the optimum would be a
bit less than the radius of the sharpest curve. So, if someone sent me a
lat/lon for, say, every 100 feet from the B2V route, I could place people
to within perhaps 10 feet of their true mileage along the route.
It really isn't too time consuming, clear a Garmin GPS's log memory at the
start of the course, set it up for 100 feet logging, drive the route, dump
the log at the end of the course, and use one of the many available
utilities to convert the log into a text file of lat/lon points.
For the algorithm, just find the closest points, and interpolate between
them (or with 100 foot points just use the closest, that gives you 50 foot
accuracy, which really is enough accuracy). I put the points into a
database table, and use SQL to find me the points I wanted, but you could
do it from a text list as well if you didn't have access to a database.
>The goal is to have the Tiger maps as temporary for now. I am working on
>creating my own maps for the race. It may not happen this year, but I'm
>going to give it a shot. I don't want to just cut and paste quick maps and
>have it look like a patchwork job. I understand the problem/uncertaintly
>with using a public mapserver! I'd love to run one local for the page - I
>have the computing power and hard drive space.
This also is pretty easy, just produce a set of tiger maps at the highest
resolution you want, and tile them. This is how the toporama and
photo-relief maps on findU are generated.
Steve K4HG
----------------------------------------------------------------------
Subject: Re: Official Baker to Vegas 2004 Tracking Website Complete
From: Steve Dimse <k4hg@tapr.org>
Date: Sun, 18 Apr 2004 12:40:39 -0400
X-Message-Number: 11
On 4/18/04 at 12:23 PM Steve Dimse <k4hg@tapr.org> sent:
>All you need for greater accuracy is more points, the optimum would be a bit
>less than the radius of the sharpest curve. So, if someone sent me a lat/lon
>for, say, every 100 feet from the B2V route, I could place people to within
>perhaps 10 feet of their true mileage along the route.
I should also have said that there still is time, if before Wed AM someone
sends me such a waypoint file, I will, before Friday morning implement
this. I'll both add it to the b2v.findu.com page, and create a separate
stand-alone table that Phil could frame into his page.
Steve K4HG
----------------------------------------------------------------------
Subject: Re: FW: [CarolinaAPRS] ICON for LANn-n
From: "Robert Bruninga" <bruninga@usna.edu>
Date: Sun, 18 Apr 2004 14:06:24 -0400
X-Message-Number: 12
Yes, I think L for LANn-N and K for LINKn-N digis but they can also be
both. Hummh...
>>>"Eric H. Christensen" <kf4otn@earthlink.net> 4/17/04 10:53:26 PM
-----Original Message-----
From: Wes Johnston [mailto:wes@johnston.net]
Sent: Saturday, April 17, 2004 09:29
To: carolinaaprs@yahoogroups.com
Subject: [CarolinaAPRS] ICON for LANn-n
Question for the group.... should we change the icon for digipeaters who
use LANn-n? For South Carolina (SCn-n) I thought about a green star with S
overlaid, but that won't work for NCn-n, because start with a N overlaid
has been used before. So perhaps we just overlay an L on the green star to
indicate LANn-n?
Other news.... I just learned that AGWPE has a digipeater client which will
route aprs packets. Since we have a limit with kpc3 TNCs only using one
callsign for UIFLOOD and UITRACE, I asked the author of this digipeater
software if he would add multiple callsigns to UIFLOOD and UITRACE. The
software is called digiplex and is available at http://www.qsl.net/lu7did/
Wes
----------------------------------------------------------------------
Subject: Re: Balloon Launch WIKI page needed`
From: "Doug Younker" <dougy@ruraltel.net>
Date: Sun, 18 Apr 2004 13:02:53 -0500
X-Message-Number: 13
Not to discourage the efforts of others but I thought I would mention the
balloons-rockets mailing list hosted on www.qth.net At one point in time
launch activity was posted there by various person flying the balloons.--73
Doug, N0LKK
----- Original Message -----
From: "Spider" <spider@rivcom.net>
To: "TAPR APRS Special Interest Group" <aprssig@lists.tapr.org>
Sent: Sunday, April 18, 2004 9:40 AM
Read previous mail | Read next mail
| |
