LHS Show Notes #032

Posted on by Russ Woodman

Texas Linux Fest promo

Contributors:

  • Shawn Powers of Linux Journal, and a recent guest on LHS, had a house fire. If you can, please help him out.
  • Google alert says LHS was mentioned in the Niagara Peninsula Amateur Radio Club (NPARC) forums, but it seems to have disappeared.
  • There's been a problem with Russ' email, k5tux@blacksparrowmedia.com, so please also copy Richard, kb5jbv@blacksparrowmedia.com, on any email until the problem is resolved.
  • Michael, DL4MGM, advises WSPR users to make sure their transmitters are on frequency, so as to avoid encroaching on the visual QRSS, particularly on 30m. He also suggests using "sudo su" to get a root shell session.
  • Ted, WA0EIR, writes to express his appreciation for Episode 029, and the plug for his website.
  • Google Alert tells us that a French website, al-aide.com, reprinted the post about Episode 029.

Announcements:

  • Texas Linux Fest will be held in Austin, TX on April 10, 2010, at the Monarch Event Center. You might even find a Linux in the Ham Shack host there! Tracy, one of the organizers of the event, is also starting another Linux-related podcast. Keep an eye on his website for the first episode.
  • We're nearing our goal of raising $750 for the LHS expedition to the Dayton Hamvention in 2010. Please click on the Donate button and make a donation, as every little bit helps. Thank you!

Links and Notes:

  • There has been a lot of ham radio involvement in the relief efforts in Haiti, through such groups as the Texas Baptist Men and SATERN. Russ points us to this YouTube video containing a contact with HH2JR, demonstrating the effectiveness of ham radio in emergency communications.
  • Richard talks about using Linux scripts to automate D-RATS transmissions (auto-QSTs). This script downloads weather information and formats it for sending through D-RATS. 
    	#!/bin/bash
	#
	# Change directory
	cd /home/richard/drats/current_conditions
	#
	# Remove the old downloaded weather file
	#
	rm KHQZ.TXT
	#
	# Download the current weather file from NOAA
	#
	wget -q ftp://tgftp.nws.noaa.gov/data/observations/metar/decoded/KHQZ.TXT
	#
	# Remove the old formatted file
	#
	rm current.txt
	#
	# Strip last line of text of the NOAA file, using sed
	# This sed command strips out everything between "Mesquite" and "Pressure"
	#
	sed '/Mesquite,/,/Pressure / !d' KHQZ.TXT > khqz1.txt
	#
	# Add a blank line to the new file
	#
	echo -e " " >> current.txt
	#
	# Copy Mesquite Weather conditions to new file
	#
	cat khqz1.txt >> current.txt
	#
	# Done!
	# A cron job then periodically sends out the contents of current.txt
	#
  • For more information on using the BASH shell and scripting, see:
  • Russ discusses the Linux "screen" command.
  • Visit us on the IRC channel #lhspodcast at irc.freenode.net or call the voice message line at 888-455-0305, or +1 417 429 4069.

Music:

LHS Show Notes #030

Posted on by Russ Woodman

Contributors:

  • Walter, WN3LIF, writes to express his appreciation for the podcast. He has successfully interfaced his FT-450 to his Linux Mint system.
  • Terry, KV6M, alerted Richard to a link spam entry in the forums at blacksparrowmedia.com.
  • Bob, VE3SRE, recently found the podcast, and has been a user of GNU/Linux for many years. He's found a good contest logging program, but neglected to mention which one. Let us know, Bob!
  • Paul, KC9QYB, of teenradiojourney.com, Kent, VE4KEH, and Bill, KA9WKA, join the roundtable discussion this episode.

Announcements:

  • Check out Russ on Hacker Public Radio! In episode 0494, Klaatu interviews Russ at Ohio Linux Fest.
  • Another generous donation came from Jim, W9GNG. Thanks very much, Jim! LHS is well on the way to their goal for sending Richard and Russ to the Dayton Hamvention 2010! If you'd like to donate, click on the Donate button at the Linux in the Ham Shack website.

Links and Notes:

  • The ARRL has an article about Senate Bill 1755 being passed in the Senate and now moves to the House of Representatives for consideration. A roundtable discussion ensues.
  • Kent, VE4KEH, joins the roundtable to discuss WSPR (Weak Signal Propagation Reporter), written by Joe Taylor, K1JT. See also the WSPRnet page for recent observations.
    • When you install the .deb package, it may not create a desktop icon. The program installs, by default, into the /WSPR directory. So, you may need to run it by doing the following in a terminal window: 
      		$ cd /WSPR
		$ ./wspr
    • Of course, you'll also need a soundcard interface to your radio. Once running, you should go to the Setup -> Station parameters menu option and enter your callsign, grid square, transmit power, and set your audio device and rig control preferences.
    • It can even be used on the experimental 600m band, if you have a license to operate there. On July 28, 2009, the FCC granted the ARRL a modified license for WD2XSH. This modified license allows the experiment to operate with 45 stations across the continental USA, Alaska, and Hawaii. So, unless you're one of the stations specifically authorized to operate on 600m, you should only provide reception reports, and not transmit on that band.
    • One final note about WSPR: you must have your computer clock set very accurately. The easiest way is to set up an NTP client on your computer to synchronize your computer clock to one of the network time protocol servers. Here is an article on setting up a Ubuntu client, which should also work for Linux Mint. Or...
    • If you RIGHT CLICK on your desktop clock and select "set date / time", there may be an option to automatically set the time. You can select the ntp.ubuntu.com server so you don't overload the public servers.
  • Paul recently built a Pixie II QRP CW transceiver kit.
  • Bill Meara, M0HBr/CU2JL/N2CQR, of the SolderSmoke podcast is also a fan and practitioner of WSPR.
  • Bill, KB3CVA, has a telnet BBS online at https://phantombbs.net.
  • Russ discusses a gizmodo article about Microsoft patenting the sudo command. It's not likely that the patent is enforceable. Don't Panic. 🙂 Articles on ars technica and Information Week have a more realistic slant on the issue.
  • Tip: to eliminate having to enter your password each time you use the sudo command:
    • First, edit the /etc/sudoers file using the visudo utility. It is considered insecure to tweak the /etc/sudoers file manually.
      • 		$ sudo visudo /etc/sudoers
    • Uncomment this line by removing the # character: 
      		# %sudo ALL=NOPASSWD: ALL
    • So it now looks like this: 
      		%sudo ALL=NOPASSWD: ALL

      and save the file.

    • Finally, add your user name to the sudo group. For example, to add user russ to the sudo group: 
      		sudo usermod -a -G sudo russ
    • Log out and in, and enjoy sudo without the password prompts.
    • Of course, if you just want to avoid repeatedly typing your password for a session, you can issue the command: 
      		sudo bash -

      which will give you a bash terminal session as root, and you can then issue several commands as root without the need for typing sudo at all.

  • Debate in the chat room about cell phones and emergency communications. Richard talks about the cell phone problems during hurricane Katrina. Most cell phone systems are designed to support about 20% of their subscribers at any given time. When an emergency occurs, the cell phone networks are quickly overloaded.

Music:

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