One of the many benefits of the D-Star System is the ability to send your GPS data through the Local D-Star System and our Worldwide Network. One thing to keep in mind is if you are sending this positioning information automatically, you may be colliding with another user attempting to be making a voice transmission.
As we know, the R2D2 affect happens when a doubling takes place and I just want to make sure everyone understands the outcome of sending GPS data in an automatic mode.
We must also keep in mind, that if you have your radio set to a memory channel that connects your transmission to another System through the Worldwide Gateway your GPS data is also being sent to the distant node.
Here is my view on this topic:
For a GPS position to be sent from a location that is NOT moving anymore often than once every 12 hours is unnecessary overhead. I think GPS positions are kept in the "heard tables" for almost 24 hours, so if you feel the need to make everyone know you are there, this can be done just as affectively as being sent once everyone 12 hours, as opposed to every ten minutes.
I have my mobile set to send my GPS data as I transmit, so I am NOT using the channel for D-PRS only traffic. My GPS position is only being sent when I talk. This is my recommendation.
If the GPS feature is needed for other times such as search and rescue then all bets are off and you should use it as it is needed.
Take a listen to 144.390Mhz, the APRS channel and you will see what I am concerned about.
I'm sure none of us want to devote any D-Star Module or System to become a D-PRS over active Node.
Author Tim K6BIV Sept 29th 2007
Below is information that was sent from Pete, the creator of the D-PRS program. For those of you running a GPS with D-Star please make sure your setup is correct.
As more and more repeaters are using the packaged javAPRSSrvr with
DStarMonitor, I ask that sysops remind users to properly configure their
radios to be seen on APRS.
For all GPS-enabled radios (radios with a GPS attached) (GPS-A mode
explained later):
Turn on GPS mode.
Set the strings to $GPGGA and $GPRMC only.
Set the GPS message (C1 on some radios) using
http://www.aprs-is.net/dprscalc.htm
If on an inactive repeater, set a beacon rate of no faster than 5
minutes.
If active on voice on the repeater, set the beacon rate to zero.
The 2820 has a new mode called GPS-A. This is the recommended mode as
it uses a CRC instead of the xor checksum used above. To use GPS-A
mode:
Turn on GPS-A mode.
Set the UNPROTO to API282,DSTAR*
Set the speed extension on.
If on an inactive repeater, set a beacon rate of no faster than 5
minutes.
If active on voice on the repeater, set the beacon rate to zero.
Note that while any radio is in either GPS or GPS-A mode, it cannot be
used for standard low speed data. If someone wishes to run an APRS
client attached to the radio, they need to use D-PRS Interface (download
from http://www.aprs-is.net/dstartnc2.htm) or javAPRSSrvr (available
only by contacting me directly). In this case, the radio will be set to
standard data mode.
Feel free to publish this to your local groups. I posted this here
because there are a lot of new users that don't frequent the Icom forums
and I thought you folks would be the best conduit to your local users.
Looking at http://www.jfindu.net/DStarReports.aspx shows a lot of
Japanese and Germans showing up on D-PRS (both using D-PRS Interface or
javAPRSSrvr independent of repeaters) but very few stations showing
through the repeaters. I am guessing that I haven't done a good job of
disseminating this information to users and hopefully this post will
help get the word out.
As a side note, I am currently gating everything heard through the K5TIT
repeaters (including the K5TIT repeater objects) to 144.39 APRS so local
analog APRS users can see local D-PRS activity. This can be easily be
done with javAPRSSrvr running as an IGate. Remember, the javAPRSSrvr
included with DStarMonitor may not be distributed. If you wish to use
javAPRSSrvr outside of this D-PRS application, contact me directly and I
will set you up in the javAPRSSrvr group where we do full support of the
application.
73,
Pete Loveall AE5PL
pete at ae5pl.net
Via Tim K6BIV July 3rd 2007
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