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LW1EAA > TODOS 21.10.17 02:31l 139 Lines 4649 Bytes #999 (0) @ WW
BID : 1204-LW1EAA
Read: GUEST
Subj: Pi Config by AG1LE
Path: IW8PGT<LU4ECL<LW1EAA
Sent: 171020/2330Z @:LW1EAA.LP.BA.ARG.SOAM #:1204 [LA PLATA] FBB7.00e $:1204-LW
From: LW1EAA@LW1EAA.LP.BA.ARG.SOAM
To : TODOS@WW
CONFIGURING RASPBERRY PI IN HEADLESS MODE
One of the first objectives was to configure RPI in headless mode. I wanted to have access to this tiny computer via SSH and VNC remotely over the network. Enabling SSH is as simple as renaming the "boot_enable_ssh.rc" to "boot.rc" in the /boot directory. You can do this even before powering up with SD card mounted on another computer and just renaming the file.
I connected LAN cable from my router and checked that I had proper IP address via /sbin/ifconfig command. I used the following steps to get VNC working:
sudo apt-get install tightvncserver - to install VNC server
tightvncserver - to set a password
sudo vi /etc/init.d/vnc - to create a startup script
sudo chmod +x /etc/init.d/vnc - to make the script runnable
sudo /usr/sbin/update-rc.d vnc defaults - to install the script for boot
The vnc script itself is below:
#! /bin/sh
# /etc/init.d/vnc
USER=pi
HOME=/home/pi
export USER HOME
case "$1" in
start)
echo "Starting VNC Server"
#Insert your favoured settings for a VNC session
su - $USER -c "/usr/bin/vncserver :1 -geometry 1024x768 -depth 16 > /tmp/vncserver.log 2>&1 &" &
;;
stop)
echo "Stopping VNC Server"
/usr/bin/vncserver -kill :1
;;
*)
echo "Usage: /etc/init.d/vnc {start|stop}"
exit 1
;;
esac
exit 0
VNC server can now be started with
/etc/init.d/vnc start
On my Mac I used Chicken of the VNC to connect to RPI. In my particular network the configuration is the following (RPI is on 192.168.1.2 port 5901) :
After these steps I am able to connect both via SSH command line and VNC to this Rasperry Pi box. See screenshot below.
The screenshot also shows some additional ham radio software that I have already installed such as FLDIGI and Xastir.
With wireless USB Wifi card installed (I used D-Link DWA-140 that I had available from other projets) RPI becomes quite portable within the range of Wifi access point. I used as wicd network manager to configure wireless USB Wifi card.
PROJECT IDEAS HOW TO USE RASPBERRY PI
RPI does have built-in audio output but no microphone or line input. Therefore you need to get a USB audio device to connect it to a radio. I did not have one available right now but wanted to test how FLDIGI would work. I installed FLDIGI using this command
sudo apt-get install fldigi
and followed these steps to configure ALSA audio. After starting FLDIGI and going through configuration screens I got it running and tested sending some Morse code. Clear audio came out from the headset plugged in. Some other hams have also tested FLDIGI with USB audio devices with positive results. FLDIGI does consume some 80% of CPU when sending - but I have not done any optimizations, just downloaded normal FLDIGI distribution from Debian repositories.
I also installed Xastir to test how APRS tracking would work on Raspberry PI. Installation is as simple as:
sudo apt-get install xastir
I did play some time with Xastir and downloaded some maps but the SD memory card was getting quite full so I decided to postpone these tests until I had a larger SD card available. Anyways, Xastir started without hickups and I was able to see Massachusetts maps and lookup stations. I ended up removing Xastir to make some space.
I also tested the built-in Midori web browser - it is not the fastest browser on the planet but did a pretty good job bringing up http://aprs.fi created by Hessu OH7LZB. See screenshot example below
I also installed nginx webserver using the instruction over here.
Based on this very cursory testing Raspberry Pi seems to run existing ham radio software quite well (given CPU capacity restrictions). I am envisioning that Raspberry Pi could be used for many different kind of Ham Radio projects, such as
Use Xastir and connect RPI to 2m/70cm hand held radio to provide a simple APRS tactical display for event organizers, like Boston Marathon
Portable beacon station that can also send telemetry information such as weather, location, even pictures from USB webcams, etc.
Use a simple Softrock type USB card and SDR software to create ultraportable Software Defined Radio
Remote control system of ham radio station over the Internet
Portable APRS digipeater
I am positively surprised how capable this tiny $35 Linux computer actually is. It certainly exceeded my expectations.
73
Mauri AG1LE
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