| Author |
Message |
    
Turfman
New member
Username: Turfman
Post Number: 1
Registered: 6-2005
| | Posted on Thursday, June 09, 2005 - 3:17 pm: | 
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I have notice mobiles with multi antennas probbly use for Dx or key downs??
does anyone out there has any info on how this works? |
Patzerozero
Advanced Member
Username: Patzerozero
Post Number: 911
Registered: 7-2004
| | Posted on Friday, June 10, 2005 - 6:32 pm: |
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build it just like a beam, except everything is done 1/4 wavelength, not 1/2. of course it isn't perfect & gain/rejection isn't the same, but it is there.
make the reflector 110% the length of the driven element, the directors about 92-95% the length of the driven element & space 'em 3-6 feet apart. that you need to experiment with to get optimal gain. as long as swr's on driven antenna are GOOD, everything else falls into place. obviously a 3 element works best on a LLLOOONNNGGG vehicle like a van, suburban, excursion, station wagon, but 2 elements will work too. with mag mounts, you could actually drive a 3 element on the road. but you'll get stranger looks then my predator does!
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Bluegrass
Intermediate Member
Username: Bluegrass
Post Number: 341
Registered: 12-2004
| | Posted on Saturday, June 11, 2005 - 4:03 pm: |
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There's two types of mobile beam antenna setups on the market right now one works and the other is a scam.The one that works is made of two 1/4 wave mobile antennas put inline on the roof of a van or suv and they have to be at least 100 inches apart to work right.Now the scam is an antenna that looks like a beam but it's small enough to fit on your car and there is NO WAY this could work,the science is all wrong so stay away from that one. |
Bluegrass
Intermediate Member
Username: Bluegrass
Post Number: 345
Registered: 12-2004
| | Posted on Monday, June 13, 2005 - 10:04 am: |
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Can't try it,Don't have a car. |
Slowhand
Junior Member
Username: Slowhand
Post Number: 11
Registered: 7-2005
| | Posted on Tuesday, July 12, 2005 - 1:08 pm: |
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I have a homebrew DDRR antenna (direct discontinunity radial radiator).It's a horizontal antenna vertically polarized and very directional.
There's a lot of info about it online. Mine is tuned for 11m and works ok. Not as good as a 102" whip, but I can go through the drivethrough at Wendys lol.
slowhand |
Harleyrdr
New member
Username: Harleyrdr
Post Number: 1
Registered: 12-2007
| | Posted on Wednesday, December 12, 2007 - 11:06 pm: |
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Lots of great info here guys.
For a few years I have been drawing up and calculting A beam that I can use for short across town TX/RX.
The idea is that I would like to hide it in my camper shell and be able to talk to my wife on the base at home with just a few watts. any advise? |
Wrk3
Member
Username: Wrk3
Post Number: 95
Registered: 4-2004
| | Posted on Thursday, December 13, 2007 - 12:58 pm: |
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go get your, amatuer ham license, you'll be surprised at what 1 watt and a very small antenna can do...
littleman/cef-354
k5wrk/cef-202
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Allagator
Advanced Member
Username: Allagator
Post Number: 776
Registered: 9-2002
| | Posted on Friday, December 14, 2007 - 7:02 pm: |
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Wrk3 ! a guy here on Copper e-mailed me a long time ago about that and ill look and see if ive still got it a post it on here for ya !!!
Allagator
CEF115 |
Harleyrdr
New member
Username: Harleyrdr
Post Number: 5
Registered: 12-2007
| | Posted on Saturday, December 15, 2007 - 8:22 am: |
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Just for the record (wrk) I Am a ham.
Wife is not. |
