John,
I should have explained in a little more detail. As you used to live in the
"Black Hole" of the Midwest, I'm still here and my QTH is in an even deeper
hole within the "Black Hole".
Anytime I can get a vertical off the ground is a good thing. Even having a
yagi on any band would underperform. Using HFTA, Even on 20-10M, I figured I'd
need a 120' rotating tower with 3-4 tri-banders to match the performance of a
single tri-bander over flat ground at 70-80'. It's quite the predicament.
That said, once my daughter is off to college, a relocation is imminent..
BTW, having a 6M beam here is impossible.
73,
Jim N9WW
James Chaggaris
President
PowerOne Corp.
2325 Dean St. Suite 800J
St. Charles, IL 60175
Phone: (630)443-6500
> On Mar 16, 2021, at 6:56 PM, john@kk9a.com wrote:
>
> When I first read N9WW's comment I did not realize that he was talking about
> a much higher frequency than top band. The 160m equivalent of Jim's 30m
> antenna would have the raised radials 160 feet high which I am sure W8JI did
> not have in the data referenced below.
>
> Jim is correct, there is a huge difference between a 30m ground mounted
> vertical and one 30 ft high. With that height you could also use a vertical
> dipole.
>
>
> John KK9A
>
>
>
> Jim N9WW wrote:
>
> I don't know. I'll take my elevated 40/30M vertical at 30' with 8 radials
> over any ground mounted vertical with 60+ radials. Been there done that.
> Huge difference.
>
> 73,
> Jim N9WW
>
> James Chaggaris
> President
> PowerOne Corp.
> 2325 Dean St. Suite 800J
> St. Charles, IL 60175
> Phone: (630)443-6500
>
>
>
>> On Mar 15, 2021, at 7:55 PM, Ignacy Misztal <no9e at arrl.net> wrote:
>> N6LF study was in OR (?) with good soil and on 40m. W8JI found by
>> measurements that elevated radials (in GA) on 160m work a few db below the
>> ground radials. His results as well as experiences of other hams are in the
>> ON4UN book. GA clay soil has perhaps average conductivity and 160m is not
>> 40m.
>>
>> WSPR is good for testing but is very slow. RBN is much faster. I call CQ on
>> one frequency, change antenna and call 2 kHz up. Then look at spots on RBN
>> and average Fun work.
>>
>> Radials (or counterpoises) can be any size. See Cushcraft R7. With an
>> electrical quarter wave their impedance is low and the vertical ca be fed
>> directly. When radials are shorter, the feed point is "hot", the coax
>> becomes a lossy radial, and all baluns except the massive one overheat. But
>> with a transformer like advocated by K2AV, no heating. FT140-61 with
>> "Ethernet" wire is good for 500W.
>>
>> One elevated radial is sufficient on the beach. I operated Stew Perry
>> contest from a beach in St George FL with inv L to a 50' tree and one
>> elevated radial 4 f high. EU was loud 2 hrs before the sunset, and 100W
>> signals louder to EU than from KW stations inland.
>>
>> Ignacy NO9E
>
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