Thanks for your kind comments Ron, much appreciated.
Hope to meet you in Dayton in 2021
73
Frank
W3LPL
----- Original Message -----
From: "Ron WV4P" <wv4ptn@gmail.com>
To: "Tree" <tree@kkn.net>
Cc: "Frank Donovan" <donovanf@starpower.net>, "160" <topband@contesting.com>
Sent: Friday, May 15, 2020 4:10:36 PM
Subject: Re: Topband: 160m Vertical
Wow,
Incredible responses in just a few min. Thanks !
This antenna will be used 90% for Contesting, but 5 days a week it will be for
casual DX on CW and SSB.
With the switching matrix I'm using at the shack, it would be hard to use a
tuner, and is what I'm trying to avoid.
On my JK 801's the Motorized inductor, controlled by a Green Heron Controller
using band data from N1MM makes it totally automatic (Flat SWR in ~ 50khz
segments)
From my talk with Mike @ Tornado Tuner, the 160m version, that I believe was
made for a short radiator is as follows...
"The Tornado 160SS will tune from about 17uH to 33uH. It has a single 27.5 turn
coil. The coil is 1/4” diameter aluminum, and the coil is 4 3/8” mean
diameter."
From the replies, I see that my approach of build it and figure out the tuning
later was the wrong misguided.
Please forgive my ignorance, I don't have the experience or background to
understand what a lot of this means. It seems that IF I wanted to use the
tornado tuner, I would need to figure out a way to model the antenna so that
adding 17uH to 33uHof inductance would allow it to tune across or close to
across the band ? And that them numbers may be way out because it was designed
for s shorter element ?
I want it Automated so I can put any poor soul I can convince to join a multi
op in the seat and just turn them loose.
Thanks again for all the great replies so far, and Frank... Loved the
presentation of the LPL history yesterday, Incredible.
Ron, WV4P
Grant, Going to read your Doc now, If it sends, I have attached a pic of the
base I built. The other next to is is one of 3 I made for the 3 Rotating Towers
I am putting up.
On Fri, 15 May 2020 at 10:34, Tree < tree@kkn.net > wrote:
One approach for the inductor that I have used when doing parasitic element
tuning is to put two SO239's in series and either put a shorted plug in for
no added inductance - or a PL259 fashioned with a few turns of heavy gauge
wire. You can label them for the frequency you are wanting.
I used that technique to go from a director to a reflector back when I was
playing with a vertical parasitic array on 160.
Tree N6TR
On Fri, May 15, 2020 at 8:28 AM < donovanf@starpower.net > wrote:
>
> Hi Ron,
>
>
>
> A more reliable approach is a tuner in your shack. The extra coax
> cable loss from elevated VSWR is insignificant on topband.
>
>
> How high up the band do you want to go and at what maximum VSWR?
>
>
> A resonant Rohn 25 160M vertical will be about 124 feet tall for
> resonance around 1820 kHz
>
> If for some reason you must install a tuner at the feed point of the
> vertical, follow Tree's advice and make it slightly short: 120 feet
> of 115 ft if you need to tune for minimum VSWR above 1900 kHz.
>
>
>
> Use a small tapped inductor to tune it around the band.
>
>
> 73
> Frank
> W3LPL
>
>
>
>
>
> ----- Original Message -----
>
> From: "Tree" < tree@kkn.net >
> To: "Ron WV4P" < wv4ptn@gmail.com >
> Cc: "160" < topband@contesting.com >
> Sent: Friday, May 15, 2020 3:18:39 PM
> Subject: Re: Topband: 160m Vertical
>
> Slightly shorter makes it easy to use an inductor to make up the
> difference. If you make it long - you can do the same with a capacitor -
> but it's typically more trouble than the inductor.
>
> Tree N6TR
>
> On Fri, May 15, 2020 at 8:15 AM Ron WV4P < wv4ptn@gmail.com > wrote:
>
> > I have built an insulated base for a 1/4 wave 160 antenna. The antenna
> > will be XXX' of Rohn 25. In searching I see people using heights from
> 115'
> > - 130' with a pretty high number around 124'.
> > I do not know how I am going to match it yet, I figure I will do my
> > research on that once it's up so I can learn while experimenting.... But
> > the height has me second guessing. I want it tunable across the band,
> > perhaps using a Tornado Tuner like my JK 801's have with a motorized
> > inductor ? But the question at hand is do I want the antenna Tall or
> Short
> > ? What is the Method behind the Madness ? :o)
> >
> > Thanks in advance,
> > Ron WV4P
> > _________________
> > Searchable Archives: http://www.contesting.com/_topband - Topband
> > Reflector
> >
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