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#1
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The Slim Jim Antenna
http://www.hamuniverse.com/slimjim.html The Slim Jim is a Vertically Polarized Omni-Directional End-Fed Antenna having considerable gain and this is concentrated almost parallel to ground toward the horizon rather than skyward making it more efficient than a ground plane type antenna by about 50 percent better. http://www.hamuniverse.com/2meter300ohmslimjim.html Due to it's SLIM {Very Thin Shape} used in it's Design, there is very little wind loading. It is fed with 50 ohm coax. http://www.ee.washington.edu/circuit...ntennas/slim_j It uses a 'J' type Matching Stub (J Integrated Matching = JIM), http://www.pcs-electronics.com/en/gu...p?sub=antennas Hense the name SLIM JIM. http://en.wikipedia.org/wiki/Slim_Jim_(antenna) Credit for the original design goes to F.C. Judd [G2BCX]. http://www.ee.washington.edu/circuit...ntennas/slim_j How to make a Weatherproof Vertically Polarised Omni-Directional Aerial http://www.irational.org/sic/radio/omni-aerial.html Choosing the Correct Antenna http://www.marcspages.co.uk/tech/antchose.htm Marc's Technical Pages http://www.marcspages.co.uk/tech/index.htm So could I make one of these Slim Jim Antennas for the Shortwave 49 Meter Band ? ? ? and just how Thin-and-Tall would it be ? ? ? What About the "Slim Jim" Antenna ? http://groups.yahoo.com/group/Shortw...a/message/9180 obtw - too fat to be called 'slim' and my name ain't 'jim' ![]() ~ RHF |
#2
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On 22 Apr 2006 11:46:13 -0700, "RHF"
wrote: The Slim Jim Antenna http://www.hamuniverse.com/slimjim.html The Slim Jim is a Vertically Polarized Omni-Directional End-Fed Antenna having considerable gain and this is concentrated almost parallel to ground toward the horizon rather than skyward making it more efficient than a ground plane type antenna by about 50 percent better. http://www.hamuniverse.com/2meter300ohmslimjim.html Due to it's SLIM {Very Thin Shape} used in it's Design, there is very little wind loading. It is fed with 50 ohm coax. http://www.ee.washington.edu/circuit...ntennas/slim_j It uses a 'J' type Matching Stub (J Integrated Matching = JIM), http://www.pcs-electronics.com/en/gu...p?sub=antennas Hense the name SLIM JIM. http://en.wikipedia.org/wiki/Slim_Jim_(antenna) Credit for the original design goes to F.C. Judd [G2BCX]. http://www.ee.washington.edu/circuit...ntennas/slim_j How to make a Weatherproof Vertically Polarised Omni-Directional Aerial http://www.irational.org/sic/radio/omni-aerial.html Choosing the Correct Antenna http://www.marcspages.co.uk/tech/antchose.htm Marc's Technical Pages http://www.marcspages.co.uk/tech/index.htm So could I make one of these Slim Jim Antennas for the Shortwave 49 Meter Band ? ? ? and just how Thin-and-Tall would it be ? ? ? What About the "Slim Jim" Antenna ? http://groups.yahoo.com/group/Shortw...a/message/9180 obtw - too fat to be called 'slim' and my name ain't 'jim' ![]() ~ RHF . . The Slim Jim is another name for a J-Pole from everything I read about it. This is a 1/2 wave antenna over a 1/4 wave matching section so your 49 meter band antenna would be rather tall (about 37 meters). Sure, you could make it ......... would be interested to see your plans for installing it 8-} Howard |
#4
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![]() wrote in message ... On 22 Apr 2006 11:46:13 -0700, "RHF" wrote: The Slim Jim Antenna http://www.hamuniverse.com/slimjim.html [snip] So could I make one of these Slim Jim Antennas for the Shortwave 49 Meter Band ? ? ? and just how Thin-and-Tall would it be ? ? ? ~ RHF . . The Slim Jim is another name for a J-Pole from everything I read about it. This is a 1/2 wave antenna over a 1/4 wave matching section so your 49 meter band antenna would be rather tall (about 37 meters). Sure, you could make it ......... would be interested to see your plans for installing it 8-} Howard With the base another 1/4 wave above ground, lo and behold the top of the Slim Jim for the 49 m band would be ==== 49 metres above ground! How slim? Probably transmission line theory here so the dimension is independent of the wavelength. You could probably use 300 ohm twin lead if it wouldn't break under its own weight. Tom |
#6
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On 22 Apr 2006 11:46:13 -0700, "RHF"
wrote: excerpted This looks like what hams call a J-pole antenna. J-poles are popular on the VHF and UHF bands. There's not much use of them on the HF bands because they would be way, way huge -- your 49 meter version would be about the size of a telephone pole. Rhf, ya really oughtta go to Amazon.com and pick up a used copy of the ARRL Antenna Book; David's advice was right on. bob k5qwg |
#7
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Them J-Pole Antennas are supposed to be good,Noc war,Tiem La?
google,Wabash Cannonball Midi Ladies and Gentlemen,Boys and Girls,,, crank that puter bolume wideeeee open.Enjoy. cuhulin |
#8
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I own a few slim jim auto car door lock picks thingy.(they look sort of
like extra long strange lookin hacksaw blades) I am not a car thief dude though. cuhulin |
#9
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#10
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There is a guy ever once in a while over there at the Goodwill store.He
has a van full of locksmith stuff.He calls himself,Flip A Lock.He has a good little business going there.Hya,Flip. cuhulin |
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