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Ham Radio

  1. Jan 29, 2009 #1

    cronxeh

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    So I did a little search and I can't seem to find any threads regarding amateur radio. Is anyone a ham out there and what frequencies do you lurk at and where? I'm a new ham, don't know why I decided to get into it but timing seems to be about right with new radios like Yaesu VX-8R and many other portable and powerful radios appearing on the market. I am in New York but it seems there aren't that many interesting conversations happening on local repeaters.
     
  2. jcsd
  3. Jan 30, 2009 #2
    I always promise myself when I build a full working transceiver from scratch I will sign up and a get a call sign. So far I have build a 3.5 MHz and 7 MHz receiver. I was particularly surprised at how crowded the bands are. Also have put together a 10 GHz receiver, but didn't really pick up anything, then had to disassemble it for parts.
     
  4. Jan 30, 2009 #3

    dlgoff

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    The only Ham I know on the forum is berkeman.
    https://www.physicsforums.com/member.php?u=8921
    I'm planning on talking a lot to him when I retire. Thought I would get involved with maybe 2m.
     
  5. Jan 30, 2009 #4

    berkeman

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    Are your interests more in local emergency preparedness group communications, or in long-distance round-the-world chatting and contesting?

    My main interest is in the former (which you can probably tell by my footer), so I mainly stay on the 2m and 70cm bands.

    The best thing you can do as a new HAM, IMO, is to find some weekly practice Nets, and participate in the check-ins. Our weekly Net is described at the website I list in my footer. You can use the ARRL.org website to find your local repeaters (or just scan around). When you get a chance, and the repeater goes quiet for a bit, you can just say, "This is <callsign>, and I was looking for information about local practice Nets. Can anyone help me out with that info?" Most likely you will get folks that come back with info on which nights and which repeaters are used, and maybe which clubs sponsor the Nets. Usually you can then find websites with info on those Nets, including the Net Control Script, which is what they are reading as the Net is conducted.

    Checking into your local weekly practice Nets is a good way to get comfortable with your radio, and how to talk well on the radio. You can also ask about local training classes for new HAMs, where you can go and learn a lot more about the best ways to use the bands and the radios.

    Then, after you are more comfortable, check out some of the big public events in your area (like the New York Marathon?) -- they are often looking for HAM radio volunteers to help with event communication tasks. One of the events that I do each year as a combination EMT and HAM is the "Tour de Max" bicycle ride that starts and ends in Palo Alto, and benifits the Lance Armstrong Cancer Research Foundations. We have to use a pretty complex combination of repeaters (including a human Relay/Repeater station) to be able to talk to all the SAG wagons down in the canyons out toward the ocean, where some of the ride is routed. GREAT practice for complex HAM communication events, er, like the next big earthquake that's unfortunately coming soon to a fault line near me....

    Post more questions if you have them. This could be a fun thread. 73, KI6EGL
     
  6. Jan 30, 2009 #5
    Berkeman isn't the only ham lurking around. ;)
     
  7. Jan 30, 2009 #6
    I'd like get into a contest and compete with homebrew rigs especially in the microwave and millimeter wave bands.

    I always wonder how do hams make contact at microwave frequencies? Do they usually decide to be on the air at certain times, and in certain direction, or do you just have to point the dish somewhere and hope you get a signal?
     
  8. Jan 31, 2009 #7

    brewnog

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    Mmmmm ham.

    When are they going to invent steak television?
     
  9. Jan 31, 2009 #8

    berkeman

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    To do the long-distance contacts and contesting, the lower frequency bands are used to be able to take advantage of skip off the ionosphere. Typically the 40m and 20m bands are used. It also helps to be in the peak of the 11-year sunspot cycle, which is coming up in a couple years. Right now the skip is a bit lame, I'm told.

    The higher frequencies are mostly line-of-sight communication, although repeaters in high places help to extend your reach for local communication. There are even "linked" repeaters that are connected via the Internet, so you can basically talk all around the world on your 2m handheld radio!
     
  10. Jan 31, 2009 #9

    cronxeh

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    IMHO long distance DXing is lame. Its just pointless. 1500 Watts may be enough for some but its just not that much to spread over the planet. And that whole internet link or EchoLink is not radio.. its .. VOIP! bleh.
     
  11. Jan 31, 2009 #10
    I noticed that during the evening, activity in the 40 meter band would sky rocket, but during day time there was almost no activity.

    Interesting to have repeaters connected via the Internet. Also heard, that amateur satellite repeaters can relay information across a larger area.

    One form of an "ultimate repeater" that is appealing is Earth-Moon-Earth (EME), that is bouncing signals off the moon to anyone across the globe that is in direct line of sight with the moon.
     
  12. Apr 27, 2009 #11

    Ouabache

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    Actually talking to someone half way across the globe on 50W is quite exhilarating. There is even a whole crowd who get a big charge, out of DXing with 5W or less. In radio jargon, this is called QRP. Transmitting 1.5KW is often overkill, more than is necessary to maintain good communication. If you were transmitting that much power, once contact is made, it is considerate practice, to reduce power to the lowest level where you can still communicate effectively with the other station.
     
  13. Apr 27, 2009 #12

    Ouabache

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    Yes on microwave bands, people may contact each other on another band ahead of time and work out a schedule (aka sked), so they know what date, time, frequency & direction (to point antenna) for meeting on the microwave bands. I've met hams with microwave transmitting equipment on mountaintops, to take advantage of line-of-sight communication that berkeman described. On a weekend hike to the top of a small mountain in New England, I found several people set up, with a horn, dish and also some multielement UHF beam antennas.

    The American Radio Relay League (ARRL) sponsor a couple of contests for operation at 10GHz and up. This year, one is scheduled for Aug 15-16, and another for Sept 19-20. A good bet for meeting other microwave enthusiasts, is to set up your equipment on a hilltop during one of those weekends.

    You may have noticed a similar behavior on the AM broadcast bands.

    It is because higher layers of the ionosphere, refract waves in the 40 meter band longer distances, after dark. During the daytime, lower layers of the ionosphere become ionized by the sun and 40m waves are not refracted very far. Depending on time of day and year, Maximum Usable Frequencies (MUF) for successful communications are determined for ionospheric propagation.
     
    Last edited: Apr 28, 2009
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