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ZL3AI > APRDIG 03.10.03 09:40l 265 Lines 9810 Bytes #999 (0) @ WW
BID : 2073-ZL3AI
Read: GUEST
Subj: TAPR Digest, Sep 30, 16/16
Path: DB0FHN<DB0RGB<OK0PPL<DB0RES<ON0AR<WB0TAX<N1UAN<ZL2BAU<ZL3VML
Sent: 031002/1509Z @:ZL3VML.#80.NZL.OC #:9570 [Chch-NZ] FBB7.00i $:2073-ZL3AI
From: ZL3AI@ZL3VML.#80.NZL.OC
To : APRDIG@WW
Subject: The APRS Raven
From: "Dick Stanich" <dick@kb7zva.com>
Date: Tue, 30 Sep 2003 21:22:53
X-Message-Number: 82
This was copied from KC5LZB's webserver. How appropriate to insert this, if
you are following the current thread <g>.
With Apologies to:
Edgar Allan Poe
Dr. Philip S. Schmidt, UT Austin
by
Bruce G. Williams, KC5LZB
The APRS Raven
Once upon a midnight dreary
As I pondered weak and weary
O'er a quaint and curious form
Of APRS Unproto Address Settings...
Suddenly there came a knocking
Not unlike a clock tick-tocking
"Sigh!", said I, my door unlocking,
Unlocked I my ham shack door.
Stood before me there a raven,
Feathers tattered, beard unshaven,
Bloodshot eye and bath untaken,
Standing in my ham shack door.
Stood I there a moment vexed,
Then I queried, quite perplexed,
"Why stand thou in my ham shack door?"
"CHANGE YOUR UNPROTO SETTING ONCE MORE!"
Upon my bookcase shelf he perched,
With glassy stare and gaze besmirched.
A wave of chill ran through my core,
As quoth the raven, "CHANGE ONCE MORE!"
Many a night the oil burned,
As summer to fall to winter turned,
While for a passing setting I prayed,
O'er my head the raven strayed.
My sight grows dim, my hand unsteady,
Another year has gone already.
My brain is racked, my head is sore.
Yet quoth the raven, "CHANGE ONCE MORE!"
B.G.W.
September 29, 2003
Dick, KB7ZVA
APRSWest
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Subject: Re: The bottom line, simply [was:***New*** TRACEn-N...]
From: "Ev Tupis (W2EV)" <w2ev@arrl.net>
Date: Tue, 30 Sep 2003 22:22:19 -0400
X-Message-Number: 83
>>Bob Bruninga wrote:
>>>Nationwide traveler: RELAY,WIDE2-2
>>
>>Isn't this really the issue? The APRS world would work if e-v-e-r-y-o-n-e
>>simply launched RELAY,WIDE2-2. Remember the chant from last year?
>>"RELAY,WIDE2-2 in 2002!"
>>
>>Ibelieve that the best path is actually RELAY,TRACE2-2 but who am I? :)
>
>But we dont even want 3 hops in many cases, so RELAY,WIDE is the same as
>RELAY,WIDE1-1 anyway. but your TRACE idea is exactly why I am so excited
>about my NEW LANn-N using UITRACE...
Suppose though, this three-tier approach to reducing congestion:
===== Tier 1 -----
Everyone agrees to use RELAY,TRACE2-2. No figuring if you're a car, a
house a digi, etc. This alone will reduce traffic overall...hands down.
===== Tier 2 -----
The only variable becomes TX interval.
Mobiles = 5 minutes
Homes/Fixed (including WX/etc) = Bob's decaying TX algorithm.
Digi's = 10 minutes
Universal acceptance of this should geometrically reduce traffic again.
===== Tier 3 -----
APRS "Official Observers" remind those that choose to not play nice about
their obligation to be good network neighbors. After a couple of nicely
worded communications I'd bet that a majority of folks will comply
willingly. The "big club" would be that those left over could eventually
be SUPLISTed at the digipeater side. This will keep traffic managable for
the forseeable future.
===== The Bottom Line -----
Get people to use APRS the way that it was designed to work without having
to introduce new technologies, aliases or infrastructures. Shouldn't we
fix a "people problem" with "people solutions"? There are some things that
technology can't fix. Human nature is one of 'em. :))
I am still a proponent of providing an accurate education, while allowing
people personal choice. It may still be necessary to launch a
RELAY,TRACE6-6 for some reason in the future. Let's not unnecessarily
block it from happening because of a few uninformed users today. Let's
inform them and motivate them to be good network neighbors.
Ev, W2EV
PS...If I know that WIDE5-5 won't work, because the path is broken
somewhere by LANn-N, yet I know that WIDE will always get through....I'm
actually encouraged to launch via W,W,W,W,W ... quite a disaster to all
involved.
----------------------------------------------------------------------
Subject: Re: Cheap GPS receivers / RS232 / Digitraveller
From: "Mike Yetsko" <myetsko@insydesw.com>
Date: Tue, 30 Sep 2003 22:36:41 -0400
X-Message-Number: 84
>So far, amazing luck finding them in the Los Angeles area, I have "hit" two
>stores and have scored both PDA and PC versions.
They didn't have them in my local store, but they did next town over. So
I 'charged' them on my AMEX and the store is transferring them in! All
three are PDA versions.
I'm assuming the software comes on CD? If someone wants, I'll swap
one of the PDA software CDs for a Laptop CD...
Mike
----------------------------------------------------------------------
Subject: Re: Cheap GPS receivers / RS232 / Digitraveller
From: Dale Blanchard <wa7ixk@arrl.net>
Date: Tue, 30 Sep 2003 19:42:44 -0700
X-Message-Number: 85
Any xx store can check inventory and tell you were all the others are. That
is how I find mine. One store in LV has 30 older pda cables , the others
hve none.
----------------------------------------------------------------------
Subject: Re: ***New*** TRACEn-N (LANn-N) Paradigm
From: "Scott Miller" <scott@home.miller.org>
Date: Tue, 30 Sep 2003 20:20:01 -0700
X-Message-Number: 86
What's the lower practical limit on packet times for 19.2k? How's the S/N
requirement compare? How's the propagation going to differ? I'm all for
high-speed backbones - and links for fixed users - but you can do a heck of
a lot with 1200 baud input. And just running faster packets isn't going to
help you much when you've still got an Aloha channel and a massive hidden
transmitter problem.
If we're going to invest in that much new hardware, instead of running Aloha
on a 19.2k channel, I'd rather run multichannel SSB PSK at 220 or 440 -
implement a real channel control protocol and use the bandwidth as
efficiently as possible.
I still think there's a lot to be said for the propagation characteristics
of 2 meters, and the robustness of 1200 baud AFSK. I wouldn't mind seeing
AX.25 tossed out the window in favor of something lighter weight and having
FEC capability, though.
Scott
N1VG
----------------------------------------------------------------------
Subject: Re: The bottom line, simply [was:***New*** TRACEn-N...]
From: "Scott Miller" <scott@home.miller.org>
Date: Tue, 30 Sep 2003 20:27:38 -0700
X-Message-Number: 87
Sounds good to me. But then I don't drive through big open stretches far
from IGATEs, either. And my home station uses a fixed path of K6SYV-10 - no
need for a RELAY, and 2-2 gives me more hops than I want. There still needs
to be some allowance for variation, but it looks like a good default. Just
make sure the client software complains loudly when you set it longer...
Scott
N1VG
-----Original Message-----
From: bounce-aprssig-31505@lists.tapr.org
[mailto:bounce-aprssig-31505@lists.tapr.org]On Behalf Of Ev Tupis (W2EV)
Sent: Tuesday, September 30, 2003 7:22 PM
To: TAPR APRS Special Interest Group
Subject: [aprssig] Re: The bottom line, simply [was:***New***
TRACEn-N...]
Suppose though, this three-tier approach to reducing congestion:
===== Tier 1 -----
Everyone agrees to use RELAY,TRACE2-2. No figuring if you're a car, a
house a digi, etc. This alone will reduce traffic overall...hands down.
----------------------------------------------------------------------
Subject: Re: [ Bob Bruninga ] Re: Digipeater Duplicate Checking is broke
From: "Gregg G. Wonderly" <gregg@skymaster.cytetech.com>
Date: Tue, 30 Sep 2003 22:42:30 -0500
X-Message-Number: 88
>So APRS was designed to allow FRATRICIDE kill out most dupes at the local
>level, and still MOST of the time, even those in the KILL area will get
>one OR THE OTHER of the packet. THus APRS was designed taking all of
>these details into account and that is why some DUPES and SOME FRATRICIDE
>are part of the design...
Last time we talked about fratricide, I volunteered a diagram. The
important detail is that if both Digis are DWAIT=0, then the area that has
zero fade is the place that is the RF middle between the digis. If they
are equal power and gain and haat, then it is smack in the middle. If I am
closer to B than to A, then B hears first and its digi is closer to A (the
same RF distance I am from B) before A's digi is encountered . A should be
'louder' at that point, and hopefully enough for capture. If you don't
balance your digis in RF power, you will not see good effects with regard
to fade.
For example if A is an Alligator at 20 watts and B is 1 watt, then the RF
power equal position will be very close to B from a FADE perspective. When
someone is exactly that distance from A, their transmissions will be hard
to decode at that same distance from B when digipeated by A and B
simultaneously.
If they are equal power, the RF middle will be equidistance from the digis.
Stations in the RF middle will have to be able to have their packets
decoded on the initial transmission, for the digi collision to not be a big
issue.
So, think about how to manage the power of the digis so that their RF
center/middle is in a flat open area that will generally allow initial
transmissions to be decoded. If you don't have this luxary, you might need
to create smaller digis distributed accordingly.
There is nothing but physics that controls the networks general behavior.
There will be some exceptions related to environmental changes, including
the presence of uneducated users.
Deal with them, but not in exclusion to logic!
If only we could have bit level timing matches like the paging networks...
My good friend, KB5ZVC can tell you how long it takes RF to go an
enumerable number of distances which he has memorized because he has to
make his paging network 'work'. We are not so bothered...
-----
gregg@cytetech.com (Cyte Technologies Inc)
---
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