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ZL3AI > APRDIG 24.05.03 11:01l 252 Lines 9647 Bytes #999 (0) @ WW
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From: ZL3AI@ZL3VML.#80.NZL.OC
To : APRDIG@WW
Subject: Re: Voice Alert on 144.39
From: Wes Johnston <wes@johnston.net>
Date: 21 May 2003 13:21:48 -0400
X-Message-Number: 13
I remember reading several years ago about a proposal to TX data on the
unused INPUT freq of a voice repeater. It was proposed that the voice
repeater RECEIVER could be replaced with a TRANSCEIVER and digipeat
packets like a normal digipeater. As you noted, megabytes of data could
be transmitted each day when the repeater was not otherwise being used.
I mean, really, how many hours per day is your local popular 2m repeater
used? Heck, what if we told all the voice users to use PL tones and if
the repeater was used for data (ie the DCD light is on a TNC), then the
repeater out put contains no PL tone. This way we could use the
repeater for data, and the voice users (listening for output of repeater
with a PL tone) would never know the data was there. This would solve
hidden transmitter problems and afford us a great antenna site for
non-live data. All that is needed is a way to make the voice user have
prioirty by making the data back off when the repeater output had a PL
tone in it.
If you did it at 9600 and kept the packets short, the voice users would
never know it was there AND would only be deprived of the input to the
repeater for a fraction of a second. And hearing something on the
output of the repeater would be enough to cause the data services to
stop for 10 minutes.
Wes
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Subject: Re: Voice Alert on 144.39
From: Alex <kr1st@amsat.org>
Date: Wed, 21 May 2003 13:27:09 -0400
X-Message-Number: 14
Bob Bruninga wrote:
>But the bottom line is that I think the philosophy of your post
>prevents much more meaningful real-time tactical useful communications
>than any possible use of Voice Alert would.
The point (there was no philosophy, merely an opposition to a concept)
of my post was to not introduce, and encourage, interference on the APRS
data stream on 144.39 by a different type of service. I find it rather
ironic that the "father of APRS" disagrees with me on this. Such is life
I guess.
73,
--Alex KR1ST (monitoring 146.52)
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Subject: Re: Voice Alert on 144.39
From: "hasan schiers" <schiers@netins.net>
Date: Wed, 21 May 2003 12:38:33 -0500
X-Message-Number: 15
<yawn mode on>
Much ado about nothing.
Is it likely that the Voice Alert Bob suggests is going to be detrimental to
APRS use on 144.390 as it exists now? If the best predictor of the future is
the past, I don't think so. Bob has brought this up MANY times over a
considerable length of time and no one, that I know of, has complained of
interference. (and very few have taken advantage of it)
The only way to arrive at the conclusion that "it's bad amateur practice",
is to look only at the theoretical possibilities of interference and said
impact, as opposed to the practical outcome of doing it. It's been done. It
hasn't been a problem.
Basically what has been done to condemn it is:
"What if everyone did this?"
Speaking of "arm-chair lawyering", the above is an old propaganda technique
(and quite discredited, I might add.). In this context, one could as easily
ask, "What if everyone transmitted a packet all at once?" These are straw
man assertions. Neither is likely to happen and everyone knows it.
Here's another misleading exaggeration of Bob's position, as I understand
him:
"let's not give anyone the impression that we consider it as a frequency on
which we think we can do whatever we want to do on it...."
Bob never suggested this and characterizing Voice Alert as such is
misleading and unfair. His suggestion is a limited, narrow use application,
NOT what is suggested by the above "do whatever we want" exaggeration.
With respect to Voice Alert being an observable nuisance due to excessive
transmissions:
It isn't happening, it hasn't happened and I doubt (in the absence of real
as opposed to theoretical evidence) it will. Voice alert has a very limited
appeal, application and impact. Within this "envelope" it just isn't a
problem. Bob's points are practical, with few if any OBSERVED negative
consequences. The criticism, on the other hand, is theoretical and
philosophical.
(This might lead to the conclusion that the criticism is "nit-picking" and
"arm-chair lawyering", but I'm not going there.)
If this were to suddenly take off (highly unlikely) and cause congestion,
then one would have a point. Until such time, it seems to be nothing more
than a solution in search of a problem.
Few will pay any attention whatsoever to the "argument". If Bob's suggestion
is functional for a given pair of aprs ops, they will use it. If it's not,
they won't. All the "sky is falling" assertions, and condemnations as "bad
practice" won't influence the practice one bit. Whether this is "good" or
"bad" amateur practice is a matter of consequence, and what hat one might be
wearing at the time.
It's a potentially useful tool. When it is needed, it is invaluable. When it
is not, it is ignored. Largely, it has been ignored. It isn't needed the
vast majority of the time. It isn't implemented the vast majority of the
time, therefore it isn't a problem the vast majority of time. I await
empirical evidence that demonstrates the infrequent and short intrusion of
Voice Alert has a more, or even approaches the deleterious effect on the
channel that normal collision rates do.
But arguing about it does get us in print and impress our friends. <g>
I don't use Voice Alert and I never have heard anyone else use it. However,
I have heard the D700 crowd occasionally key up on the wrong side of the
radio. (hmmm...that might have been me). What if everyone did that? Oh...I
forgot...they do....I've heard it....and it didn't really matter.
<yawn mode off>
....hasan, N0AN
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Subject: Re: Voice Alert on 144.39
From: Bob Bruninga <bruninga@usna.edu>
Date: Wed, 21 May 2003 13:39:47 -0400 (EDT)
X-Message-Number: 16
On 21 May 2003, Wes Johnston wrote:
>I remember reading several years ago about a proposal to TX data on the
>unused INPUT freq of a voice repeater. It was proposed that the voice
>repeater RECEIVER could be replaced with a TRANSCEIVER and digipeat
>packets like a normal digipeater. As you noted, megabytes of data could
>be transmitted each day when the repeater was not otherwise being used.
Here is the link:
http://web.usna.navy.mil/~bruninga/seventy.txt
Yes, the voice users would never notice anything, they could use the
repeater at any time just by pressing PTT. Yet 40 Mbytes per day per
repeater channel could be distributed throughout hamdom...
de WB4APR, Bob
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Subject: Re: Voice Alert on 144.39
From: Alex <kr1st@amsat.org>
Date: Wed, 21 May 2003 13:47:13 -0400
X-Message-Number: 17
"B. Hildebrand" wrote:
>Voice Alert is a valuable asset, should be encouraged and used as
>good amateur practice. It probably should be included in the APRS
>specification.
Any chance that Voice Alert will be part of the OpenTrac specification?
73,
--Alex KR1ST (back to inventing new mode, suppressed carrier FM)
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Subject: AVR Butterfly
From: "Sadowski, Allan" <allan.sadowski@ncshp.org>
Date: Wed, 21 May 2003 15:45:11 -0400
X-Message-Number: 18
Hopefully it'll be cheap... given that the seminar is free... and they
will give one to every attendee I figure the price will be low. Make an
interesting "HUD" type of display maybe... and power... look at what it
runs on for battery !!!!
It has 16 Kilobytes of memory in Flash.... 1kilobyte of SRAM, 512 bytes
of EEPROM, speaker, serial port, LCD display, temp sensor, light sensor,
buttons....
Though the 4 x 25 segment LCD is limiting... the program running can
scroll the characters...aka a rolling display...
http://www.avrfreaks.net/Home/butterfly/butterfly.php?PHPSESSID=7dfbb6a
4ec8f3a839f07c2554fcb1f9f
http://www.atmel.com/dyn/products/tools_card.asp?tool_id=3146
ALOHA
AH6LS
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Subject: La Crosse WX Station
From: Ralph Milnes <ralph.milnes@verizon.net>
Date: Wed, 21 May 2003 16:45:44 -0400
X-Message-Number: 19
Anyone know .. is it possible to use a La Crosse weather station (WS-2010)
as part of a remote (no computer) APRS station?
It looks like I might need to buy the PC interface module, but I don't know
what data packets that outputs.
And then maybe feed it to a Byonics WXTrak?
Anyone done it?
Ralph KC2RLM
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[commercial content deleted]
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Subject: Re: Throat Mic (Was: Install on BMW Motorcycle)
From: "Richard Amirault" <ramirault@erols.com>
Date: Wed, 21 May 2003 19:05:23 -0400
X-Message-Number: 21
By the way .. Radio Shack now sells a throat mike. Look it up in the catalog
... oh, that's right .. they don't have a catalog anymore :-( Actually, I
saw in on display in a store a few weeks ago.
They USED to sell a ear canal mike that might also fit the bill for bikes ..
but you can only get them on eBay nowadays :-(
Richard Amirault N1JDU Boston,
MA, USA
www.erols.com/ramirault "Go Fly A Kite"
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