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ZL3AI > APRDIG 25.05.03 10:08l 286 Lines 11304 Bytes #999 (0) @ WW
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From: ZL3AI@ZL3VML.#80.NZL.OC
To : APRDIG@WW
Subject: RE: APRS-NET COncept!
From: Miller Scott Contr 30SCS/FTI <Scott.Miller@vandenberg.af.mil>
Date: Thu, 22 May 2003 18:08:03 -0000
X-Message-Number: 27
Is the intention to do this on 144.39?
I think you'd really need to look at some sort of packaging and filtering
technique - possibly stripping images, or at least including inline images
in the same package to prevent multiple requests. Raw HTTP over AX.25
probably isn't a great idea. With packaging and compression, it could be a
lot more efficient than HTTP over TCP/IP over AX.25, though.
Scott
N1VG
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Subject: Area Objects test
From: "Spider" <spider@rivcom.net>
Date: Thu, 22 May 2003 11:46:39 -0700
X-Message-Number: 28
Folks, just to let you know.....
There is an Alpha test going on and we will/have been placing some Area
Objects out in the Pacific Ocean, west of Baja. These are only test Area
Objects and will not be there too long.
Jim, WA6OFT
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Subject: Re: Voice Alert on 144.39
From: "Demetre Valaris" <sv1uy@sv1uy.ampr.org>
Date: Thu, 22 May 2003 21:52:32 +0300
X-Message-Number: 29
On 22 May 2003 at 12:44, Bob Bruninga wrote:
>Demetre,
>
>I was told that my choice of PL 100 was a poor choice for Europe that uses 50Hz
>power mains. If this is the case, then maybe Europe should choose another PL
>tone? But if your squelch has not heard anyone, or any noise, then I guess
>that means that 50Hz power buzz does not cause a problem?
>
>Let us konw.
>Thanks
>Bob
Hi Bob,
I haven't noticed anything nasty, although there is some breakthrough from
time to time, but Athens has so much RF floating around that one cannnot
tell if it is the 50HZ power lines that cause this or other RF
transmissions. Now I will start taking extra notice for a week and let you
know. I say extra notice, because I have been monitoring 144.800 KHZ with
my CTCSS set on 100HZ for a year now, while mobile, and I have not heard
any noise that got on my nerves, if you know what I mean, but then again
some of us can tolerate noises more than others. All I can hear is other
people's packets that also TX on PL100, which are very few, and I believe
they are QRV on VOICE ALERT too, although I have never called anyone in
Athens area yet because APRS traffic is bad and I do not want anyone
telling me off! hi hi hi!!!!!!!!
After a week of looking out for any noises using 100HZ, I will try to
remember to use another CTCSS tone and see what happens.
I will let you know!
BTW this VOICE ALERT is a great idea and I can understand who uses it and
he is in simplex range for a VOICE ALERT contact when my radio triggers the
loudspeaker due to the 100 HZ tone they use, as I do, when they TX.
This Saturday evening we have the SV Hamfest here in Athens and I will take
my TH-D7 with me in order to see what happens next to many of us operating
APRS at the same time! I will let you know what happens!!!
So keep up the good ideas coming Bob and keep nagging us from time to time
because we forget about good ideas!!!
===
73 de Demetre SV1UY
e-mail: sv1uy at sv1uy.ampr.org
PACKET MAIL: SV1UY@SV1UY.ATH.GRC.EURO
http://www.athnet.ampr.org/~sv1uy
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Subject: RE: APRS-NET COncept!
From: Bob Bruninga <bruninga@usna.edu>
Date: Thu, 22 May 2003 15:42:12 -0400 (EDT)
X-Message-Number: 30
On Thu, 22 May 2003, Miller Scott Contr 30SCS/FTI wrote about the ANET
idea of letting HAM radio provide a linke from the "field" back to the
internet in support of special events:
>Is the intention to do this on 144.39?
No.
On a local channel properly coordinated with the local powers that be.
Probably one of the unused packet frequencies that these days are dying.
It would be brought up as needed.
I also am not too concerned over the usual concerns
of Internet "content" on HAM radio for 2 reasons:
1) This system will only be activated on a case basis
to serve a specific need at a specific time. Thus
it is ACTIVELY being monitored while in use.
2) Since every user station captures every page
transmittted and one window on the desk top will
maintain a list of all the WEB pages transmitted
and WHICH USER CALLSIGN requested them,
accountability is tracible to the end user.
>I think you'd really need to look at some sort of packaging and filtering
>technique - possibly stripping images, or at least including inline images
>in the same package to prevent multiple requests. Raw HTTP over AX.25
>probably isn't a great idea. With packaging and compression, it could be a
>lot more efficient than HTTP over TCP/IP over AX.25, though.
As long as the end user sees the same web page over the link as he expects
over a landline. "Efficiency" was not necessarily the driving objective
(although of course every trick in the book should be used to get it)...
THe idea was that once the event begins, the data begins to stream. The
delays will be MUCH SLOWER than what people expect, but then only the
first person to request a given page will have the delay. Everyone else
grabs if for free and has instant access.
For a given event, the anticipated WEB pages can be "pre-requested" so
that they begin strreaming immediately. And other WEB pages, (such as
FINDU or APRSERVE pages) can be listed for automatic refresh. But one
transmission updates everyone.
I guess this does get more complicated because normally a URL request and
a WEB response traverse a virtual connection. I am thinking in terms of
UI packets and so there will be holes unless there is some kind of filling
Anyway, I hope the ANET[user] software is background (with a
control window) yet the user simply uses his Browser as is...?
Bob
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Subject: RE: APRS-NET COncept!
From: "Joseph C. Bender" <n8xre@benderhome.net>
Date: Thu, 22 May 2003 15:46:25 -0400 (EDT)
X-Message-Number: 31
Miller Scott Contr 30SCS/FTI said:
>Is the intention to do this on 144.39?
More importantly, how about the rest of us who don't have Kenwood xxxxx
radios?
--
Joseph C. Bender
n8xre at benderhome net
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Subject: RE: APRS-NET COncept!
From: Bob Bruninga <bruninga@usna.edu>
Date: Thu, 22 May 2003 16:05:37 -0400 (EDT)
X-Message-Number: 32
On Thu, 22 May 2003, Joseph C. Bender wrote:
>Miller Scott Contr 30SCS/FTI said:
>>Is the intention to do this on 144.39?
>
>More importantly, how about the rest of us
>who don't have Kenwood xxxxxx radios?
Build or buy any 9600 baud modem of your choice. In this application ANY
9600 baud TNC will do. But thousands of us are driving around with the
Kenwood in our vehicles already, so I just used it as the baseline for
discussion...
The way I see it, we have the TNC's. They can do 9600 baud (with proper
planning) We have the need for linking the internet out to the field...
Maybe its time for someone to take this on.
de WB4APR, Bob
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Subject: Ultra simple MIC-e repeater
From: Wes Johnston <wes@johnston.net>
Date: 22 May 2003 16:09:29 -0400
X-Message-Number: 33
Here's the plan yall..(Trying to sound like Dr Evil in Austin
Powers)....
********************************************
Simple dual baud rate MIC-E for voice repeaters.
1)A 9600 TNC in kiss mode hooked to the discriminator out of your local
voice repeater. Any packets heard @9600 on your local repeater input
frequency will be send out it's serial port via a diode to 1200 baud
TNC. The serial OUTPUT is run thru a diode to another TNC (see step 3)
9600 baud packets are quiet and short. Most voice users won't even
notice them since they sound like a slow closing squelch tail on the
repeater.
2)A 1200 baud tnc's audio input is hooked to the repeater's receive
audio. As with the 9600 baud tnc above, any packets heard at 1200 baud
on your local repeater's input frequency will be sent out this TNC's
serial port. The serial OUTPUT of this TNC is run thru a diode.
You can optionally interrupt the COR line of the repeater with a relay
by using the CD LED so that 1200 baud packets are muted.
3)A 1200 baud TNC in kiss mode is wired to TX only to a radio on
144.39. It will need to have a ground, PTT, and TX audio hooked to the
radio. It would be a good idea to use the XCD input pin hooked to a
squelch indicator on the radio (usually a pin in the mic jack). The
serial INPUT of this TNC is tied to the two diodes coming from the other
two TNCs.
Make sure you setup CWID before going into KISS mode on the TNC doing
the transmitting on 144.39.
Now what have you got?
Kenwood radios can transmit mic-e packets at 9600 or 1200 baud. Tiny
trak and tapr's Mic Encoder can transmit MIC-e packets at 1200 bauds.
Any 1200 or 9600 packet heard on the input of your repeater will be be
retransmitted in an unmodified form out onto 144.39. 9600 baud packets
are downconverted to 1200 for use on 144.39. 1200 baud packets stay at
1200 baud as they are passed on to 144.39.
Now the above steps may lead you to believe that this is a requires 3
TNCs... that's not true... the 1200 baud TNCs mentioned in steps 2 and 3
are simply one TNC looped back on itself. This can be done inside the
DB25 shell on the serial cable.
Make no mistake this "bent pipe" is generally not good practice because
if two bend pipe digipeaters can hear each other's output, they will
loop indefinitely. However, since the input to this repeater is not on
a packet frequency, the TNCs will never hear any data on 144.39. There
won't be a loop.
I'd rather use a PC running digined to do this, but this method is rock
solid and simple. The CWID is not exactly a great thing on 144.39, but
it meets the FCC requirements for ID.
I have done the "bent pipe" from 9600 to 1200 bauds here with two TNCs
and two radios and a kenwood HT origniating the 9600 packets. Works
like a champ every time.
Thanks to Alex kr1st for pointing out that kpc3 tnc in kiss mode will
CWID.. this makes this ultra simple setup legal <grin>. Does anyone
know if the paccomms and MFJs will CWID in kiss mode?
**************************************************
Poor man's MIC-e repeater
It would be nice to make sure that packets get muted so that voice users
are not upset by other's sending 1200 baud mic-e bursts. But this
requires that the TNC be at the repeater site. If for some reason, you
wish to decode mic-e and digipeat these packets to 144.39 and can't get
to the repeater site, you can simply do it at your home QTH. I haven't
found a repeater yet that won't pass 1200 baud packet from it's input to
it's output. Just program your normal aprs rig with an odd split in
memory (tx=144.39, rx=<your repeater output frequency). That is the
quick and dirty method. If you were going to do this permanently, you'd
probably want to use a 2nd receiver such as a scanner for monitoring the
repeater output, and use the XCD pin on your TNC to prevent collisions
on the aprs frequency.
Wes
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