Darryl Smith darryl at radio-active.net.au
Sun Jan 6 19:54:45 EST 2013

On this subject, there is a great video on YouTube detailing APRSC, the
open source APRS-IS server. One of the cool things is how the author has
moved the server for Finland onto a Raspberry Pi!


Also check out APRS.FI Behind The Curtains


And Practical Handheld Software Defined Radios


I should point out though that these are from the TAPR/ARRL Digital
Communications Conference, and I am a TAPR Board Member.


Darryl Smith, VK2TDS POBox 169 Ingleburn NSW 2565 Australia
Mobile Number 0412 929 634 [+61 4 12 929 634 Int] - 02 9618 6459

On 6/01/13 7:47 PM, "Tony Hunt" <wavetel at internode.on.net> wrote:

>Your assuming that the connection is good between aprs.fi and the
>servers. Its not. Its a proven fact that theres packet loss at times
>our part of the world and servers like aprs.fi and findu.com . Ive seen
>hours go by in times past where the track of a vehical is just missing on
>findu and aprs.fi although it was gated properly to the net and also seen
>others logged into the same server via the net. It appears there are
>that the international connections (offshore) get pretty flakey. Thats ok
>your surfing the net because your browser or email just takes a bit
>on that route until it resolves but with the aprs servers the packet is
>and then its just lost and if you want to see if the server got it then
>just didnt get there because you guessed it, it was lost.
>We have previously had discussions about having regionalised mirrors for
>things like findu and aprs.fi as these servers basically cop the full
>international load. The chances of seeing any locally based
>appear soon does not seem like its going to happen.
>If your still not 100% sure the problem is not at your end then try
>up a different machine to monitor the situation. If you can organise a
>independant 3G connection on a laptop to monitor it then great. Try
>the laptop into the same server as your wx station and see if you loose
>data at the same time as you find lost data on aprs.fi happening. You
>also log the laptop into a different server and see the efffect.
>try these . You will find that first and second are one of the same.
>first/second is currently feeding the Tier2 system via T2HUB4
>  and third is feeding via T2HUB1
>You could try the ZL servers as well first.aprs.net.nz as they may take
>different routes to get to aprs.fi via Hawaii to LA perhaps. Many of our
>routes leave Australia via Singapore Japan and Asia.
>Tony Hunt VK5AH wavetel at internode.on.net
>----- Original Message ----- > Date: Sat, 5 Jan 2013 15:51:38 +1030
>> From: "Grant" <vk5gr at bigpond.com>
>> To: <ozaprs at aprs.net.au>
>> Subject: [OZAPRS] Problem with rotate.aprs.net.au address?
>> Message-ID: <000a01cdeb04$89dd7140$9d9853c0$@com>
>> Content-Type: text/plain; charset="us-ascii"
>> Hi Folks,
>> As I have put in the subject here, I am wondering if there is a problem
>> with
>> the way the rotate.aprs.net.au address is working?
>> By way of explanation for what has lead me to ask the question, here is
>> tale.
>> For some time I have been having problems getting my weather station
>> (VK5GR-1) which is connected via the Internet to have its packets
>> picked up by the APRS net (and in particular be displayed on
>> I
>> was beaconing every 15 minutes, and would sometimes see no frames
>> on
>> aprs.fi for several hours, and at times days.  I originally put it down
>> a
>> number of factors including:
>> .         The PC was connected via WiFi to my router
>> .         The Wifi was unreliable and appeared to drop back to one way
>> comms
>> .         The NetGear Cable Wifi router appeared to lockup the Wifi port
>> .         The Weather beacon was running on a very slow (low powered)
>> based PC and perhaps was dropping packets on the LAN
>> .         The eCumulus software I was using doesn't hold up the
>> connections
>> permanently (unlike UIView) and the slow PC was taking too long to
>> re-establish the IP connection for the software to send the data each
>> Slowly I have been working through trying to eliminate each of these. I
>> have
>> 1.       Removed all ancillary programs from the PC (I didn't replace
>> as
>> previously it has run on this machine fine for about 2 years)
>> 2.       Replaced the Wifi with Cat5 cable again
>> 3.       Cleaned up the disks and verified free space etc etc
>> 4.       Updated to the latest versions of software and drivers
>> 5.       Changed from DHCP LAN Address assignment to fixed IP within my
>> NAT'ed LAN (removes the NetGear router interfering with IP
>> 6.       Changed the interval from 15 to 5 minutes
>> It was this last step that started to see some positive results. This
>> me suspicious. So, I then looked at the server address I was connecting
>> and have now moved it back to second.aprs.net.au and set the interval
>> now at 10 minutes. Since doing this yesterday morning, I appear to have
>> not
>> missed a packet! Even through the weather PC and the router both got a
>> toasty with the 44deg C day we had (the rooms they are in are not air
>> conditioned here).
>> The only significant change I made that made an impact to the packet
>> reliability was changing from rotate.aprs.net.au to second.aprs.net.au.
>> So while I am still not convinced it isn't something at this end (most
>> likely with the crappy netgear router), I thought it significant enough
>> ask - is there something unique about rotate.aprs.net.au that could be
>> impacting things?
>> Anyone have any thoughts?
>> I am working to actually place the entire weather station permanently
>> on RF soon but would like to keep a reliable output weather stream in
>> meantime making it into the APRS-IS network to monitor conditions here
>> we
>> head through next week's heatwave.
>> Regards,
>> Grant VK5GR
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>OZAPRS at aprs.net.au

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