FM Antenna DEMO

Discussion in 'The Demo Room' started by crackerkorean, Apr 25, 2006.

  1. crackerkorean

    crackerkorean Striving for Polymathdom!

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    Got permission from the big guys to do this so here it goes.

    My father and I have developed a high gain FM antenna because im cheap. Well the antenna we designed and built is so good that I would like to start selling it here on AK for other members to enjoy.

    Here are some quick specs on size and performance.
    ~9DBd
    24" Boom
    2 ~48" elements

    With my Rotel RT-1220 I was able to pick up a staion over 100 miles away with this antenna. Granted it was not in stereo but the signal was strong enough that I could listen to it.

    For you techies here are some performance plots for you to look at.
    NOTE:All DB specs in the charts are in DBi, to get DBd you would subtract 2.15.
    DBi - decibles over isopole
    DBd - decibles over dipole

    So like the cable thread just sign up to be put on the list. I will try to get the antenna out early next week. It all depends on how the end of my semester and finals go.

    These will be for sale soon and each sale will yeild a donation to AK.


    ***ADENDUM***
    I also wanted to mention that this antenna is not made with the cheap/thin TV antenna tubing. I use the same stuff my father uses on his HAM antenna.s .058 thick aluminium.
     

    Attached Files:

    Last edited: Apr 25, 2006
  2. Sandy G

    Sandy G Spiteful Old Cuss Moderator Subscriber

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    How much ?
     
  3. crackerkorean

    crackerkorean Striving for Polymathdom!

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    Well the demo is free just gotta pay shipping to the next person.
    I am going to be putting the two element (shown above) at $65 with $5 going to AK from every sale.

    Performance wise these are alot cheaper than many out there. Dont let the number of elements fool you.

    Also it was just brought to my attention that some of you guys in Can might want to demo this also.
    To save everybody shipping I wold like to make a list and have it in the US and then to Can so it only crosses the border once.

    so when you put your name on the list please specify where you live.
     
    Last edited: Apr 25, 2006
  4. radioactive

    radioactive tube gear fanatic

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    sign me up for the canadian leg of the demo mike.im in winnipeg manitoba.

    chris
     
  5. bolly

    bolly Lunatic Member

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    I'll give her a whirl too mike. :)
     
  6. radioactive

    radioactive tube gear fanatic

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    ha ha greg i beat you by 5 mins.stand inline.
     
  7. bolly

    bolly Lunatic Member

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    thats ok chris, you'll have to pay to ship her to me, I'll have to pay to ship to the next guy...come on Bigerik(or someone else in Toronto) :naughty:
     
  8. Yamaha B-2

    Yamaha B-2 registered user

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    Hmmm.......my six (6) element Radio Shack yagi costs $24.99. And is ~the same size. You might want to run the same test against the RS yagi and see what results you get. http://users.tns.net/~bb/rsfmyagi.htm

    You might want to post your info here: http://groups.yahoo.com/group/fm_antennas/ and here: http://groups.yahoo.com/group/FMtuners/ These two groups have a large number of professional rf engineers and SERIOUS rf hobbiests in attendance and can provide you with some great feedback (but be prepared to take some heat if they don't like it). Good luck. In the meantime, I'll just send in my $5 to AK. :D
     
    Last edited: Apr 25, 2006
  9. crackerkorean

    crackerkorean Striving for Polymathdom!

    Messages:
    2,180
    Location:
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    My elements are ~48" and my boom is only 24" long. I am not sure of the boom length on the RS antenna but I can almost guarentee that my 2 element antenna is shorter in boom length than the RS antenna.


    I used two different programs to help me come up with the values from my antenna and they have been run many times in different configurations. According to both programs my antenna yeilds ~9-10DBd across the FM band.

    Thanks for the yahoo group link. I have requested to become a member. The more feedback the better. I just know what the modeling program tells me and what I have heard with my tuner. I was able to get two radio stations over 100 miles away with my Rotel RT-1220.

    As for the donation, I am sure that AK would appreciate it.

    ***EDIT***
    I also wanted to note that the antenna that is being demoed is built with .058 thick aluminium tubing, as opposed to the much thinner TV antenna style tubing.
     
    Last edited: Apr 25, 2006
  10. Bigerik

    Bigerik AK Subscriber Subscriber

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    Damn right I am in on the Canadian leg! :)
    Nice addition to the test program, this is.
    Any chance we could get some guys at Krell to throw us some amps at some point? :D
     
  11. Strawman

    Strawman Moderator

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    I'm in again.
     
  12. Yamaha B-2

    Yamaha B-2 registered user

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    Posted a link to this thread in the FM Tuners Forum to see if anyone will pick up on it. I also sent in my $5 to AK.
     
    Last edited: Apr 25, 2006
  13. airjam

    airjam New Member

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    1
    Count me in on the Canadian side also.

    Brampton near Toronto Ontario
     
  14. Paul C

    Paul C Super Member

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    Put me down.

    And I'll be picking up a Rat Shack antenna soon, so will do a comparison.
     
    Last edited: Apr 26, 2006
  15. Johncan

    Johncan returning member Subscriber

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    I want one!! And I am not returning it :dammit:
     
  16. cabinover

    cabinover Dazed and Confused Subscriber

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    I'd be interested in a demo, throw me on the list please.
     
  17. Donkey!

    Donkey! AK member

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    That's how I found it. This is interesting. I have built so many damn antennas in my day. I have a J-Pole you guys would probably like to play with.

    Im just curious, how do you intend to use this beam. Vertical or horizontal?
     
  18. crackerkorean

    crackerkorean Striving for Polymathdom!

    Messages:
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    Location:
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    I decided with a 2 element YAGI for the extra gain. And for me the Front to Back is low enough so that I can point it away from atlanta and still get other stations with atlanta behind me.

    I have been using this one horizontally.
     
  19. Yamaha B-2

    Yamaha B-2 registered user

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    Starting to get some responses on the FM Tuner Forum. My post is #36720. Got there and you can follow the thread responses. The couple I've read state that the gain calc's are too high.
     
  20. crackerkorean

    crackerkorean Striving for Polymathdom!

    Messages:
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    Location:
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    We are reanalyzing our product to coinside with FM broadcast Engineering specs, and once we complete the reanalysis and field trials the prototypes will be manufactured and distributed.
     

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