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Mobile Base Station setup help.

Riverman,

"Didn’t say they were resonant. Those were made in the days before I purchased my RigExpert AA-54 so had no way of measuring reactance. Like many, the only thing I had to go by was SWR. Adjusted lengths for lowest on CH 20."

now we know where the 103" figure comes from in the gp calculations. unfortunately resonance has nothing to do with swr. resonance is based on the length of the radiator and swr on the feedline is the result of some combination of R & jX other than R=50 jX=0 present at the antenna feedpoint. changing the length of the radiator is not changing the swr, it's changing the resonant frequency to some other frequency showing a lower swr while leaving the radiator resonant far from the intended operating frequenc(ies)y. antennas don't have an swr. thanks for the input.
 
Riverman, unfortunately resonance has nothing to do with swr. resonance is based on the length of the radiator and swr on the feedline is the result of some combination of R & jX other than R=50 jX=0 present at the antenna feedpoint. changing the length of the radiator is not changing the swr, it's changing the resonant frequency to some other frequency showing a lower swr while leaving the radiator resonant far from the intended operating frequenc(ies)y. antennas don't have an swr. thanks for the input.

Yep. (y)
 
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Capt Crunch,

" They say how to figure it out but I don't know about dividing wavelengths well at all."

1λ (1.0) wavelength, 360 degrees @ 27.185 mhz. = 36.196 feet.
7/8λ (.875) wavelength, 315 degrees @ 27.185 mhz. = 31.671 feet.
3/4λ (.75) wavelength, 270 degrees @ 27.185 mhz. = 27.147 feet.
5/8λ (.625) wavelength, 225 degrees @ 27.185 mhz. = 22.622 feet.
1/2λ (.50) wavelength, 180 degrees @ 27.185 mhz. = 18.098 feet.
3/8λ (.375) wavelength, 135 degrees @ 27.185 mhz. = 13.573 feet.
1/4λ (.25) wavelength, 90 degrees @ 27.185 mhz. = 9.049 feet.

multiply feet times 12 for length in inches.
 
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Capt Crunch,

" They say how to figure it out but I don't know about dividing wavelengths well at all."

1λ (1.0) wavelength, 360 degrees @ 27.185 mhz. = 36.196 feet.
7/8λ (.875) wavelength, 315 degrees @ 27.185 mhz. = 31.671 feet.
3/4λ (.75) wavelength, 270 degrees @ 27.185 mhz. = 27.147 feet.
5/8λ (.625) wavelength, 225 degrees @ 27.185 mhz. = 22.622 feet.
1/2λ (.50) wavelength, 180 degrees @ 27.185 mhz. = 18.098 feet.
3/8λ (.375) wavelength, 135 degrees @ 27.185 mhz. = 13.573 feet.
1/4λ (.25) wavelength, 90 degrees @ 27.185 mhz. = 9.049 feet.

multiply feet times 12 for length in inches.

Maybe I said that wrong I was trying to figure out how to do multiple shorter radials. I was reading about radials and multiple radials and they were saying to divide wavelengths to get multiple shorter radials. But then again I am still reading up on it as they say that it's called elevated radials which works different than ground plane radials, so getting a little confusing again now. I was trying to find out if I can make sure to radials all the way around the mount as they were talking about 16 and 32 radials being The Sweet Spot and I have at least two foot of space all around my antenna mount if this is the same kind of radial I am looking to do I think it will be better to have shorter radials all the way around my mount then just two wires for ground plane. But then again I'm still reading lol.
 
I believe high numbers of shorter radials pertain to ground mounted antennas with the radials actually on or buried in the ground itself.
For elevated antennas, I believe 2 to 4 radials, each 1/4 wave in length are sufficient and recommended. (y)
 
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"when discussing radial lengths, I usually talk about λ/4 or λ/8 radials. mention of a λ/4 radial leads most of us to think of a 20-meter long radial on 80 meters. a wire up in the air at heights where you normally have an antenna has a velocity factor of about 98%. when you bring that same wire close to ground, the velocity factor starts dropping rapidly below a height of about 0.02 wavelength. on the ground, the velocity factor is on the order of 50-60%, which means that a radial that is physically 20 meters long is actually a half-wave long electrically!"

.02 of a wavelength @ 27.185 mhz.. 36.196 X .02 = 0.72392 feet or 8.687 inches.

https://www.qsl.net/l/lu7did/docs/QRPp/09.pdf
 
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So giving an update on this. I am not going to be hooking that antenna set up here. As I mentioned it is not my house and when I got everything together it's too obtrusive to me. And thats not even thinking of the earth ground I should do for safety which is another thing, and it's not my house to possbly burn down. My landlord is a great 84 year old retired italian mason and enjoys what he has. That being said I will be raising this setup about 4.5ft on a pole, and separating it from the fences connection as some suggested. I am taking this new route because when there is lightning I can just disconnect the cable from the antenna at my window. I will have to deal with whatever the outcome is and it will be good as I mainly run mobile and this was just for listening basically. I would like to thank everyone for all the help and information that has been given and I have learned some new things as well. Once I get it set up I will let everyone know the results. 73s for now. Thanks again.
 

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