Thanks for your kind comments Ron, much appreciated.
Hope to meet you in Dayton in 2021
73
Frank
W3LPL
- Original Message -
From: "Ron WV4P"
To: "Tree"
Cc: "Frank Donovan" , "160"
Sent: Friday, May 15, 2020 4:10:36 PM
Subject: Re: Topband: 160m Vertical
Wow,
-Original Message-
From: Dave Cuthbert
Aloha Ron.
EZNEC ROHN25 model:
128' resonant at 1.796 MHz, 35 +j0 ohms
115' resonant at 2.000 MHz, 35 +j0 ohms
115', 1.800 MHz, 25 -j46 ohms
115' 1.800 MHz, 4.1 uH base series inductor, 25 +j0 ohms
Dave KH6AQ
Anybody on the list use one of these? Having difficulty with setting up mine.
Some help would be awesome.
Thanks,
Ed NI6S
_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
EZNEC Rohn 25 top loading
115' Rohn 25
4 spoke top hat, 66" x 0.500" tubing
SWR in a 30 ohm system (match 30 ohms to 50 ohms)
1.800 MHz, 2.2:1
1.900 MHz, 1.2:1
2.000 MHz, 2.2:1 KH6AQ (formerly WX7G)
On Fri, May 15, 2020 at 8:13 AM Jim Brown wrote:
> On 5/15/2020 8:27 AM,
That's the method I use. That said, Frank's idea of a tuner in the shack makes
more sense, especially with a 100' run of LDF4. I've done it both ways. The
reason for the L-network match is that it permits a shorter top wire which is a
physical advantage in my situation. I use a few turns on
On 5/15/2020 8:27 AM, donov...@starpower.net wrote:
A more reliable approach is a tuner in your shack. The extra coax
cable loss from elevated VSWR is insignificant on topband.
I strongly agree with this.
Another suggestion. Do your best with what you can rig, using as much
top-loading as
If you have a quater wave vertical resonating on 1,9 Mhz, the swr 1:2 bandwith
will be > 200 kHz.
Even if your feedline has 3 dB attenuation (that is a lot on this band), the
additional loss will be 0,33 dB.
Nothing to worry about, and not at all a reason to use a tuner at the base of
the
Tree, Thank you very good idea. One more reason to hang out here. I used the
Harpin match as Jay mentioned on my inverted L worked great. 73 Fred KB4QZH
Original message From: Tree Date: 5/15/20
11:34 AM (GMT-05:00) To: Frank Donovan Cc: 160
Subject: Re: Topband: 160m
Matching an inverted L using a single shunt coin (Hairpin) Also gives you
a DC path to ground. No capacitors needed.
https://www.arraysolutions.com/pdfs/Tuning_160m_Vertical.pdf
Regards to the group
Jay, WX0B
Jay Terleski
Array Solutions
214 954 7140
On Fri, May 15, 2020 at 11:00 AM wrote:
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
Speaking of broadbandedness.
OK, what differences would it be bandwidth wise?
Where does it matter to get the wider bandwidth/
At the feedpoint?
At the far end?
In other words, you get broader bandwidth using Rohn 25 than using say a
4" irrigation pipe.
Now how about if you have a broad
I would favor using an inductor. Tune it for the lowest part of the
band. Then using a relay or two, you can short out turns if you want
to move higher in the band. Although I think you will find using Rohn
25, it will be pretty broad.
73
Ken K4ZW
On Fri, May 15, 2020 at 11:28 AM 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
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
Myself I like longer,
Yes gotta use a cap, But not too big a deal, I find more variable caps
at hamfests than roller inductors.
PLUS, longer raises the natural impedance too closer to 50 ohms. Of
course NOT 50 but higher than 1/4 wave resistance.
Joe WB9SBD
Sig
The Original Rolling Ball
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 wrote:
> I have built an insulated base for a 1/4
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
I followed the instructions on the W0BTU website, which gave me all the
information I needed to set up three, two-wire Beverages here.
I found the easiest wire to work with for the baluns is what I stripped out
of two-pair indoor telephone wire. It has four colours PVC insulation on
thin
18 matches
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