[TowerTalk] Vertical question

[john at kk9a.com]

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