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Distance between antennas




titanNV

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#1
Looking to add a UHF (GMRS) base antenna to my rooftop fairly close to existing dual band (2m/70cm) base antenna. How close together can they be without causing interference?
 

NYECOGunsmith

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#2
Keep them at least 1/4 wavelength (1/4 wavelength on the longest wavelength, the 2 meter one here) apart and you should be OK.................unless you're not! :devilish:o_O:ROFLMAO:
 

Harley

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#3
Keep them at least 1/4 wavelength (1/4 wavelength on the longest wavelength, the 2 meter one here) apart and you should be OK.................unless you're not! :devilish:o_O:ROFLMAO:
That has got to be the shortest, most useless response I have ever seen you make since I've been here! :LOL::ROFLMAO:
 

NYECOGunsmith

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#4
That has got to be the shortest, most useless response I have ever seen you make since I've been here! :LOL::ROFLMAO:
Keep it up Harley, and I will post the math on how to finger it out, in great detail, complete with schematics, Venn diagrams, pie charts, and a full bibliography, and you will end up eyes glazed, drooling and babbling before you are a tenth of the way through the post! o_O:devilish::ROFLMAO::ROFLMAO:
 

Harley

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#5
I was expecting no less!

F on presentation. :LOL:
 

NYECOGunsmith

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#6
Make up yer mind boy, you complain if I give all the details, you complain if I just give the answer without explaining how to get it..........................oh, now I get it, you're channeling my late wife! :ROFLMAO::ROFLMAO:
 

titanNV

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#7
2ft should suffice, but I think I have enough room to go a full wave length.

Mucho thanko!
 

NYECOGunsmith

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#8
Here ya go Harley, here's the math behind the answer.....
1646712910149.png
1646712941249.png

That's the start of it, then you progress to
1646712975294.png

That will get you the 5th order harmonic, now you just have to reduce the variable "ph sin L-k cosL " by Riddecki's constant N times, where N is equal to the number of beers you have in the fridge, and ....Bob's yer uncle, there's the distance to separate the antennas.

Happy now? o_O:ROFLMAO:
 

Harley

BANNED FOR LIFE+35 Because he dared me to do it!
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#9
Here ya go Harley, here's the math behind the answer.....
View attachment 124770
View attachment 124771

That's the start of it, then you progress to
View attachment 124772

That will get you the 5th order harmonic, now you just have to reduce the variable "ph sin L-k cosL " by Riddecki's constant N times, where N is equal to the number of beers you have in the fridge, and ....Bob's yer uncle, there's the distance to separate the antennas.

Happy now? o_O:ROFLMAO:
Give us about 40 years and Bob and I will have that figured out!
 

NYECOGunsmith

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#10
Fastest way to get the answer is to bring some primo Meowi Wowi Catnip over and ask Attack Cat 2.0 for the answer, or ask Dyna.
Cats are hyper intelligent beings here studying us, this kind of math they learn in kittengarden.
 

NYECOGunsmith

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#12
I'm still working on the proper length of tin foil to wrap on my tv's rabbit ears to get good reception! (I'm sure Steve has an equation for that too! :ROFLMAO:)
Number of beers you plan to consume per hour while watching TV times 1.616, equals screen staying clear as you get blurry...or.....
For general viewing of non important stuff, 6 inches will do, but for important stuff you watch when the warden isn't home, like the Playboy channel, well, you need more inches! :devilish:o_O:ROFLMAO: