My thoughts on MF and LF.

Discussion in 'The Low Bands - 630/2200 Meters - VLF' started by WA4ILH, Nov 9, 2017.

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  1. WA4ILH

    WA4ILH Subscriber QRZ Page

    I have made this statement several times before but I will make it again. Medium Wave and Long Wave frequencies work best over water paths. Second best is areas which have excellent ground conductivity such as parts of Michigan and Wisconsin.

    When I was stationed in Norfolk, Virginia, I lived very near the coast, on the banks of the Elizabeth River in Portsmouth. I could copy Maritime coastal stations and Non Directional Beacons (NDB) from hundreds of miles away and occasionally at night, European Broadcast stations in their “LF” band around 200 KHz. Of course, these broadcast stations were (are) running many hundred thousand watts (some over a MW) to an excellent ground plane. I remember when my ship left Norfolk for the Mediterranean, on several occasions, we copied Norfolk ComSta (NAM) in the vicinity of 150 KHz all the way to Gibraltar. Again, they were probably running about 10 KW, but my point is, if you live very near the coast, you have a huge advantage. Ground Conductivity here in South Texas is poor. I probably won’t try these new bands for a while.

    Tom WA4ILH
     
  2. K9STH

    K9STH Ham Member Volunteer Moderator QRZ Page

    ILH:

    You need to move to north Texas! The ground conductivity around here is the best in the entire United States! There used to be no less than 3-commercial antenna ranges within 3-miles of my house here in Richardson, Texas!

    ground conductivity Collin County.jpeg

    The "X" at the south end of Collin County is where my house is located.

    Glen, K9STH
     
  3. WA4ILH

    WA4ILH Subscriber QRZ Page

    Roger that Glen. The only time I ever lived in an area which had excellent ground conductivity was in the summer and fall of 1973 when I briefly worked at the Allegan FCC monitoring station. I lived in an appartment in Holland, MI (also excellent) and worked lots of countries on the bottom half of 80M with 100 watts. I knew a guy out in Odessa, Tx who claimed his counterpoise was an abandoned oil well that was several thousand feet deep. Don't know if that was true or not but he had 5B DXCC.
    Tom WA4ILH.
     
  4. WD4IGX

    WD4IGX Premium Subscriber QRZ Page

    That is a map of ground conductivity? Is there a link where such a map can be viewed or created for other areas?
     
  5. K9STH

    K9STH Ham Member Volunteer Moderator QRZ Page

    The ground conductivity map, provided by the FCC, can be downloaded from the following site:

    https://www.fcc.gov/media/radio/m3-ground-conductivity-map

    It is a "zip" file and "un-zips" when run. It takes a little bit of experimentation to find just which section covers your area because the sections are not labeled in the most rational manner!

    Glen, K9STH
     
  6. KB4QAA

    KB4QAA XML Subscriber QRZ Page

    http://conductivity.parksdigital.com/

    Here's the whole FCC color conductivity map laced together, online. One of our members created this a couple years ago.

    ---------------------------------------------------------------
    About the Ground Conductivity Map
    The Project
    Hi, I'm Aaron Parks, KC8FQD, and I put this together because it looked like it would be fun to do and I figured other folks would be able to make some use of it. I think it will be particularly useful and interesting to other amateur radio operators.

    The Map
    The map itself is assembled from scans provided by the FCC as Figure M3. They have a small page about it.

    Leaflet is used for the interactive map, along with a couple of plugins.

    Location Data
    When the map page loads, it first tries to find your position using the geolocation API. This isn't yet as widely supported as would be convenient and even where it is supported, many people choose to turn it off for privacy.

    If the geolocation API is unavailable or doesn't return a location, an attempt is made to guess an approximate location from your IP address using the services of ipinfo.io.

    It is also possible to look up your address (or any address, really) using the search box at the top right of the map. That geocoding (address to position conversion) is done by Nominatim.

    Privacy
    Location data is used to show you a marker on the map. It doesn't come back to me. Don't worry, I'm not snooping on your ground conductivity.

    I do collect some basic information about how the site is used via Google Analytics. Google has their own, rather lengthy, privacy policy.

    Conclusion
    That's it! I hope you enjoy it and I hope to see you on the bands.
     
    W1ADE and W4RAV like this.
  7. WD4IGX

    WD4IGX Premium Subscriber QRZ Page

    Thanks both!

    I'm in a zone of 2, as is my dad's property up in TN. Not the best for this kind of thing. Worse, most of the places I'm thinking of buying some getaway land in a couple of years, maybe to be eventually used for a retirement home, are also in the 2 zone. Some slight bit of area that would be under consideration are in a 4.

    Oh well, we deal the hands dealt us. Won't stop me from trying it out if other stars align.
     
  8. K8JD

    K8JD Ham Member QRZ Page

    I am just northwest of Detroit and I have heard the VLF NDB beacons as far as Winnipeg.
    So I am starting to look into building up some kind of CW Transmitter for 630M , and investigating some antenna possibilities .
    I have a big wooded area behind my house that I have my 160M and 80m dipoles already hanging.
     
  9. W9AFB

    W9AFB Ham Member QRZ Page

  10. KA5ROW

    KA5ROW XML Subscriber QRZ Page

    You have heard the term stuck in the middle. I am at 15 in Poteau,OK. So I guess I will find out.
     

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