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Thread: SWEDISH VERY LOW FREQUENCY (VLF) TEST TRANSMISSION ON 17.2 kHz

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  1. #1
    Join Date
    Jul 2002
    Location
    Somalia website 2: http://sites.google.com/site/somaliaamateurradio
    Posts
    250

    Default SWEDISH VERY LOW FREQUENCY (VLF) TEST TRANSMISSION ON 17.2 kHz

    The VERY LOW FREQUENCY station in Sweden, call sign SAQ will be using CW (Morse code) on 17.2 kHz and will start transmitter tuning at 0730 UTC.

    VLF station SAQ (now a member of the Swedish Amateur Radio Association) will be on air Wednesday 24th December 2008 at 0800 UTC and 0830 UTC.

    Anyone with a computer can download the free Computer Soundcard Based SAQ ELF (Extremely Low Frequency 300 Hz to 3 kHz) and VLF (3 kHz to 22 kHz) Receiver from Johan SM6LKM on http://web.telia.com/~u33233109/saqrx/saqrx.html

    Connect a long wire into the computer microphone socket.
    I use a 1.8 MHz half wave dipole.
    Disconnect the antenna before a storm and when not in use to avoid lightning danger.

    The next test after this one will be on Sunday 28th June 2009.
    Listeners can send QSLs via the bureau.

    A Merry Christmas and a Happy New Year to all.

    73,
    Sam Voron VK2BVS, 6O0A.
    http://somaliaradio.blogspot.com

  2. #2

    Default

    I confess, it never occured to me to use the input to the sound card for such; I have to try that.

  3. #3
    Join Date
    Apr 2003
    Location
    MI
    Posts
    6,178

    Default

    Quote Originally Posted by k5co View Post
    I confess, it never occured to me to use the input to the sound card for such; I have to try that.
    The AOR 5000 tunes to 5 KHz. However a SC will do DSP averaging. Hmm. I have a loop antenna for that low. Maybe I'll try it.


    Cortland
    KA5S
    Last edited by KA5S; 12-23-2008 at 06:30 PM.

  4. #4
    Join Date
    May 2001
    Location
    Scottsdale
    Posts
    2,252

    Default

    This program seems to work with Wine, so MAC (Intel) and Linux folks can try it. I only wish we could tune higher but our sound cards are too slow.

  5. #5
    Join Date
    Jul 2002
    Location
    Somalia website 2: http://sites.google.com/site/somaliaamateurradio
    Posts
    250

    Default VERY LOW FREQUENCY REPORT FROM SYDNEY, AUSTRALIA

    This test was a great opportunity to do more VLF listening.

    I always enjoy listening on the ULF Ultra Low Frequency band 1 Hz to 300 Hz, ELF Extremely Low Frequency band 300 Hz to 3 kHz and VLF Very Low Frequency band (3 to 30 kHz).

    My last great catch was an 8 kHz transmission from a VLF transmitter/receiver water pipe leak locator that was used by a plumber searching for the location of a water leak from pipes under my garden.

    Using the SAQ receiver and a 1.8 MHz antenna I was not able to hear the test transmission from SAQ Sweden on 17.2 kHz in Roseville, 6 km north of the Sydney harbour bridge during my local Australian daylight afternoon summer time.

    I did hear the Australian North West Cape submarine broadcast station in Western Australia on 19.8 kHz at signal strength -65db and the Russian submarine broadcast station on 18.1 kHz at signal strength -75db.

    There is a story about the SAQ Very Low Frequency Sweden transmitter and antenna in the current ARRL QST magazine January 2009 on page 38.

    Station SAQ Sweden use no valves and no transistors to generate 200 kW (200,000,000 Watts).

    They do this with a mechanical AC generator which was the technology to generate high power radio waves before valves and transistors were invented.

    The VLF station is maintained as an emergency communications system to communicate with Swedish submarines in the Atlantic Ocean and elsewhere.

    In the event of an electro magnetic pulse capable of destroying transistor radios it seems that Sweden is maintaining this very interesting VLF transmitter in case all else fails.

    What did you hear?

    73,
    Sam Voron VK2BVS, 6O0A
    Email somaliahamradio@yahoo.com
    Web http://somaliaradio.blogspot.com

  6. #6
    Join Date
    Apr 2003
    Location
    MI
    Posts
    6,178

    Default

    Quote Originally Posted by vk2bvs View Post
    This test was a great opportunity to do more VLF listening.

    I always enjoy listening on the ULF Ultra Low Frequency band 1 Hz to 300 Hz, ELF Extremely Low Frequency band 300 Hz to 3 kHz and VLF Very Low Frequency band (3 to 30 kHz).

    My last great catch was an 8 kHz transmission from a VLF transmitter/receiver water pipe leak locator that was used by a plumber searching for the location of a water leak from pipes under my garden.

    Using the SAQ receiver and a 1.8 MHz antenna I was not able to hear the test transmission from SAQ Sweden on 17.2 kHz in Roseville, 6 km north of the Sydney harbour bridge during my local Australian daylight afternoon summer time.

    I did hear the Australian North West Cape submarine broadcast station in Western Australia on 19.8 kHz at signal strength -65db and the Russian submarine broadcast station on 18.1 kHz at signal strength -75db.
    Good stuff Sam. Me, I didn't wake up in time. Ah well, there's 90cm of snow out there and dragging the loop away from the house would not be fun in the dark. If I leave it out it will need waterproofing.


    Cortland
    KA5S

  7. #7
    Join Date
    Aug 2001
    Location
    West Haven, CT
    Posts
    64

    Post

    Quote Originally Posted by k5co View Post
    I confess, it never occured to me to use the input to the sound card for such; I have to try that.
    I would suspect that you'd want to do SOMETHING to eliminate the INTENSE interference you're going to get from the local power lines.

    What do you usually hear from an audio amp when you touch (or connect only one wire to) an input? Usually, a very loud hum or buzz from your AC power. That's most likely want your sound card is going to "hear" as well.

    A small audio transformer used as a choke to computer ground should be enough to allow audio frequencies above a few hundred Hz while greatly attenuating that low freq noise from the AC lines. (Use a capacitor between the input and your antenna, like .1 or .05 ufd.) Also keep in mind that the AC line noise conatins MANY harmonics!
    73 de N1NKM
    "No Kidding, Man!"[FONT="Verdana"][SIZE="3"][SIZE="3"][/SIZE][/SIZE][/FONT]
    [url]www.mymorninglight.org/ham[/url]

  8. #8
    Join Date
    Jan 2006
    Location
    Woodlands, MB, Canada
    Posts
    218

    Default

    This has me intrigued.. I listen to just about everything including the non directional beacons below the AM broadcast band from 200 to 530 Khz.

    I've got a full sized 160 meter dipole, but a quick calculation shows it's less than 10% of a half wave at 17 Khz.... (Using it is kind of like using a 2 meter dipole to recieve signals on 20 meters) I guess the optimum antenna would be some sort of giant receiving loop, but I haven't got the energy to actually assemble one.

    When I get into the city this weekend, I'm going to pick up what I need to assemble a PL259 to 3.5mm adapter so I can plug my antenna directly into my sound card and see what happens.

  9. #9
    Join Date
    Jul 2002
    Location
    Somalia website 2: http://sites.google.com/site/somaliaamateurradio
    Posts
    250

    Default Listening to VLF in the snow.

    Hello KA5S,

    Sounds like you have a great Christmas antenna thing to do.

    Better than building a snow man?

    Here in Sydney we never see snow.

    Its now 78 degrees, a sunny normal Christmas day.

    Great for VLF listening.

    Keep warm up there.

    73 from down under,

    Sam VK2BVS, 6O0A.
    Email somaliahamradio@yahoo.com
    Web http://somaliaradio.blogspot.com

  10. #10

    Default

    This is FASCINATING! I have to try to listen to the next test in June!! It's hard to find a radio that's not deaf below 100 kHz but I think my AOR AR8600mkII with a VLF converter will be my best bet!

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