venerdì 30 gennaio 2015

Mobilinkd TNC2 on Ubuntu Linux

First step let Ubuntu to see the modem

My bluetooth usb adapter is an old emtec one, Ubuntu 14.04 does recognize it immediately after plug-in in the usb port.

Then I've switched on Mobilinkd TNC2, the blue led started to flash.

The first problem is that the enclosed Ubuntu bluetooth manager does not works with a Bluetooth serial module of the Mobilinkd TNC.

As I try to configure it with the bluetooth manager it request to set a random password on the modem that is not possible.

So install the blueman bluetooth manager:

sudo apt-get install blueman.

Now start blueman and magically it's possible to pair the Mobilinkd TNC and see it as a rf serial /def/rfcomm0

Try to see if the modem is accessible from the serial port with a terminal, like moserial.

The serial port speed should be 115200.

For example in moserial I saw:

== BeRTOS AVR/Mobilinkd TNC2
== Version
== Voltage: 4026mV
== Starting.

Second step AX.25 settings

First install the necessary AX.25 packages:

# sudo apt-get install ax25-tools# sudo apt-get install ax25-apps

Then, configure your AX.25 ports to allow you to access the TNC.

sudo vi  /etc/ax25/axports:
# /etc/ax25/axports


# The format of this file is:


# name callsign speed paclen window description


packet0     IN3AQK-9         115200  255    2      144.900 MHz (1200 bps) Packet

Pay attention no empty lines are allowed!

Then connect the AX.25 packet0 port to the tnc with the command:

sudo kissattach /dev/rfcomm0 packet0

The result is:

AX.25 port packet0 bound to device ax0

With ifconfig you could see a new ax25 port with the ip

Then it's time to call for example:

axcall packet0  IR3DG

Now its, possible to point Xastir to the just created port packet0

To be continued

sabato 17 gennaio 2015

APRS on QRP Portable

In addition to having a strong passion in QRP activity, especially in portable, have always been passionate about economic digital technology, Such as packet radio, APRS and TNC, NO D-Star, NO DMR.

In the 90s my
packet radio station  and packet radio satellite gears has been continuously on for years, it was my internet at zero cost.

During my
QRP HF portable activities, I had the necessity to have a wireless data communication system, not based on cellular technology.
Also because often where I go there is no cellular coverage while the packet-aprs system works.

In addition as software developer work I have developed wireless tracking systems, very similar to APRS.

I have used for some time the tinitrack4, both as aprs and kiss modem.
It works fine, but had some problems, such as:

Too sensibile to the RF emitted by the transmitter
Too many connectors
External power supply.
Casino to connect to Android.

Last Monday I stumbled on this project:

Bought immediately and arrived yesterday with DHL.

It is a packet radio
kiss modem.
In practice it means that it is a stupid modem, not a real or TNC APRS one.

Therefore it requires an external system such as Android.

The modem is very small, it attaches directly behind RTX handheld with a rubber band.

It has an internal lithium battery that allows 48 hours of work.

Beautiful thing is that the serial port is bluetooth and then zero cables except the one with the RTX.

The system do NOT works with iOS systems, because they do not have support of Serial over Bluetooth.

It interfaces seamlessly with APRSDroid and BTTerm for Android, but it also goes with
APRS clients and  Terminals for Windows and Linux.

The configuration is done in 5 minutes with a simple program for Android or Windows.

This system can be seen on, I can indicate on which frequency are QRV on HF during my activations.

Can I send
sota spots , read the cluster and even send an email.

The modem is the little box behind the wouxung

APRS data on my tablet over bluetooth