Thursday, December 19, 2013

Argentdata Tracker 3 Mini

My Argentdata Tracker 3 Mini, it's been lying around for almost a year, before I start to play with it again. Our group ordered few units in bundle and most of it have been dispatched to top mountain digipeater. Following the success of OT2m, the T3 mini also worked well. I've test with 3-4 type GPS receiver, but none of it work with T3 mini...something must be wrong.

The T3 is lying around because it not capable to use it as tracker. I've tested with the larger version of T3, and it working well as expected. When swap with the mini version, it can't run. The T3 mini is not accepting the GPS data.

After swapping the RX and TX line of serial port and changing to port B it still not go through... Then I start to email Scott, and he guided me through a few troubleshooting method. I report back every his opinions. And yet still no success.One of his guide is to monitor incoming data string from Port A using terminal via Port B, I use the GPS simulator, and I could see GPS string coming in.The T3 mini led blinking! I swap to GPS receiver,no data coming in. Led also stop blinking.

Suddenly I remember when I'm troubleshooting the KF-163 ( from Jancorver Museum), the KF-163 also not transmitting even I've tried many GPS receiver. The I refer back to the manual, and I see they only using the GPS TX data line only, they didn't connect the GPS RX data, just leave it.
I heat up my soldering iron, and remove the GPS RX data, plug it back to T3 mini, and power it up...and I can see the GPS string in the terminal, LED also blinking. YES!! it can work as tracker now.

 I wrap the wire, put the T3 mini back in a box, move it to my car, replace it with my current OT1+, and start tracking again.
I email Scott and notify him the problem.

Friday, November 29, 2013

Raspberry Pi + svxlink = Low power echolink node

What is the easiest way to get echolink node up and running on raspberry pi? Surely, get a premade image which has everything inside. I've created one image which can fit into 2GB SD card for this, just follow the following steps to get it up and running:

For hardware, you need to have the following:
    • Raspberry Pi for sure, with a minimum 4GB SD card
    • A USB echolink interface, can be commercially sourced or DIY. There are many DIY schematics out there that you could follow.  
    • Here is the configuration on how to get the things working together, courtesy of website:

For software:
    1. Download the following prepared image from google drive, it is based on raspbian-2015-02-16 image and has pre-installed svxlink-14.08.
    2. Unzip the file and copy it to your SD card using the following instructions that can be found here.
    3. Boot up the RasPi, if you do not have an HDMI monitor, you may want to access the RasPi from your terminal emulator (putty or the like), connect the RasPi to your router via CAT5 cable. 
    4. To find the IP address of your RasPi, just go to your router status and look for the hostname raspberrypi. 
    5. Use SSH connection, logon to the RasPi using the default username/password which should be: pi/raspberry
    6. If you've bigger SD card then the 2GB image, you may want to use fullest capacity of the SD card, run the raspi-config command as sudo:
      • $ sudo raspi-config
      • Choose the first option to expand rootfs. Exit when done.
    7. Edit the following config files for svxlink (command):
      • $ sudo nano /etc/svxlink/svxlink.d/ModuleEchoLink.conf (edit the callsign - use sysop -L callsign, password, sysop, location and description)
      • $ sudo nano /etc/svxlink/svxlink.conf (edit the callsign), if you're using echolink interface that uses VOX, just leave the others as is. Edit the APRS info too as required.
    8. To tune the mic/speaker, use alsamixer:
      • $ sudo alsamixer (use the up/arrow to tune the volume, right/left to move between speaker and mic sliders). 
      • If the slider has MM underneath them, it means that they're muted, press 'M' to unmute.
    9. You should be done with the configuration, you may run the svxlink now to test it out.
      • $ sudo svxlink
    10. Your node should appear in the echolink now. Try to use your PC or android client to connect to your node and see if it is working. You may need to configure your router to allow echolink to work, use port forwarding and forward the UDP port 5198-5199 and TCP port 5200 to your RasPi IP address.
    11. If everything is working as expected and you want to run svxlink as a service, follow the steps here. The link to auto start the server has been vanished, so the best to do an autostart of the svxlink is by running the following command (if the /etc/init.d/svxlink is not present, copy the script over from the source under distribution/debian/etc/init.d/):
      • update-rc.d svxlink defaults

Tuesday, November 12, 2013

APRX Package

Offcial APRX package now is 2.07
The package can be obtain directly at
For open-WRT package 2.08, you can get it at 

MyAPRS has new Hosting!

Thanks to Wak Rejal (9W2XRX) for the hosting..
We hope that we can maintain the hosting
Please feel free to visit the APRSC site at

Friday, March 15, 2013

iGate/DiGipeater Filter

All commands to the server start with the word "filter" and followed by one or more filter specifications. For instance, to specify all packets near Dallas Texas plus all NWS bulletins, you would use the following line:
filter r/33/-97/200 t/n
The default filter is not to pass anything in addition to what javAPRSSrvr will pass. So a user-defined filter port (14580) will pass messages to the client and any gated station, and nothing else until a filter definition is added. Multiple filter definitions can be setup separated by spaces. If any of the filters find a match the packet is passed.

You can prevent the filter from passing certain packets by prefixing the filter parameter with a hyphen (-). This tells the filter to approve any packets that match the include filters except those that match the exclude filters. Standard port functionality such as messaging for IGates is not affected.
For instance, to get all stations within 200 km of me except stations with the prefix of CW, I would use:
filter m/200 -p/CW
The server-side filter uses decimal degrees for latitude and longitude. The command "filter default" resets the filter to the predefined filter for that port.

The filter command may be set as part of the login line, as an APRS message to SERVER, or as a separate comment line (#filter r/33/-97/200). The prefered method is to set the command as part of the login which is supported by most current APRS software.
Below are the available filters (4.0 updates are highlighted):

Parameter Filter Type Description
r/lat/lon/dist Range filter Pass posits and objects within dist km from lat/lon.
lat and lon are signed decimal degrees, i.e. negative for West/South
and positive for East/North.
Up to 9 range filters can be defined at
the same time to allow better coverage.
Messages addressed to stations within the range
are also passed.
p/aa/bb/cc... Prefix filter Pass traffic with fromCall that start with
aa or bb or cc...
b/call1/call2... Budlist filter Pass all traffic from exact call: call1, call2, ...
(* wild card allowed)
o/obj1/obj2... Object filter Pass all objects with the exact name of obj1, obj2, ...
(* wild card allowed) (spaces not allowed) (| => / and ~ => *)
os/obj1/obj2... Strict Object filter
Pass all objects with the exact name of obj1, obj2, ...
(* wild card allowed) (| => / and ~ => *) Objects are always 9
characters and Items are 3 to 9 characters. There can only
be one os filter and that filter
must be at the end of the line.
t/poimqstunw t/poimqstuw/call/km Type filter Pass all traffic based on packet type.
One or more types can be defined at the same time,
t/otq is a valid definition. p = Position packets
o = Objects
i = Items
m = Message
q = Query
s = Status
t = Telemetry
u = User-defined
n = NWS format messages and objects
w = Weather
Note: The weather type filter also passes positions packets
for positionless weather packets.
The second format allows putting a radius limit
around "call" (station callsign-SSID or object name)
for the requested station types.
s/pri/alt/over Symbol filter pri = symbols in primary table (| => /)
alt = symbols in alternate table (| => /)
over = overlay character (case sensitive)
For example:
s/->     This will pass all House and 
Car symbols (primary table)
s//# This will pass all Digi with
or without overlay
s//#/T This will pass all Digi with
overlay of capital "T"
d/digi1/digi2... Digipeater filter The digipeater filter will pass all packets that have
been digipeated by a
particular station(s) (the station's call is in the path).
This filter allows the * wildcard.
a/latN/lonW/latS/lonE Area filter The area filter works the same as rang filter but the
filter is defined as a box of coordinates.
The coordinates can also been seen as upper left coordinate and
lower right. Lat/lon are decimal degrees.
South and west are negative.
Up to 9 area filters can be defined at
the same time.
e/call1/call1/... Entry station filter This filter passes all packets with the specified callsign-SSID(s)
immediately following the q construct. This allows filtering based on
receiving IGate, etc. Supports * wildcard.
g/call1/call1/... Group Message filter
This filter passes all message packets with the
specified callsign-SSID(s) as the addressee of the message.
Supports * wildcard.
u/unproto1/unproto2/... Unproto filter This filter passes all packets with the specified destination
callsign-SSID(s) (also known as the To call or unproto call).
Supports * wildcard.
q/con/I q Contruct filter q = q Construct command
con = list of q Construct to pass (case sensitive)
I = Pass positions from IGATES identified by qAr, qAo, or qAR.
For example:
q/C    Pass all traffic with qAC
q/rR Pass all traffic with qAr or qAR
q//I Pass all position packets from
IGATES identified in other packets by qAr or qAR
m/dist My Range filter This is the same as the range filter except that
the center is defined as the last known position
of the logged in client.
f/call/dist Friend Range filter This is the same as the range filter except that
the center is defined as the last
known position of call.
Up to 9 friend filters can be
defined at the same time.

APRS® - APRS Software and Bob Bruninga, WB4APR.