102 whippers

bamminjammin

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Sep 2, 2020
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18
So if I put 102 inch whip out as a base antenna and connected it to another 102 inch whipper with a T adapter about 60 feet away, would it get out better? Just better reception? Screw SWR up all to heck? Just curious.
 

MDScanFan

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Jan 23, 2010
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What frequency(ies) are you trying to use? T junction aside...

The reason to use a displaced set of antennas is to increase gain in a given direction and/or reduce gain in given direction. If done correctly, then across a limited set of frequencies you get a directional pattern (ex North and South) and reduced gain elsewhere (ex East West). Maybe this is what you want or maybe it isn’t. As the frequency is increased the antenna spacing becomes electrically long and you get multiple lobes of higher and lower gain along the horizon. That’s never a good thing and you are better off with a single antenna.

Accordingly, it’s not a good solution for wideband reception and it gets harder to get things right for higher frequencies where the spacing and cable lengths are more critical. It is relatively easy to pull off for HF and maybe VHF Low. The max spacing not to exceed is usually around one wavelength.

Whether this is a good path to take depends on what you are trying to do (frequencies, do you want a more directive pattern, can you just go higher with what you have, etc).
 

bamminjammin

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Sep 2, 2020
Messages
18
11 meter. I have one with two radials. Reaches North, South and East 10 to 13 miles. The other would be a little higher but with more trees around, possible 4 radials.
 

n0nhp

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Dec 1, 2005
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Grand Junction
Using all 50 ohm cable (assuming equal lengths of legs and perfect cable and a bunch of other things) Your antenna system would show 25 ohms impedance to the radio.... bad SWR.
Using specific lengths of 90-100 ohm cable, you could make a bi-directional antenna system at broadsides to the antennas.
Co-phasing antenna systems is a project in physics with a side of black magic.

Bruce
 
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