Topband: Rohn 25 Vertical questions.

[w5zn at w5zn.org]

Ron,

When you start preparing for phase 2, here are some notes on my 
installation presented at the 2018 Dayton Antenna Forum that is linked 
from Tim's K3LR website that should be a good reference in addition to 
Tim's excellent data contained in the "Low Band DXing Handbook":

https://www.kkn.net/dayton2018/2018_Dayton_Antenna_Forum-160_meter_TX_Array.pdf

My driven element is Rohn 25. It has been in use as a 160 meter TX 
antenna (originally as a shunt fed tower) for almost 25 years. I 
initially did not have any connection across the joints however after 
several years I became concerned there may be an issue, no particular 
reason or data to suggest such other than a "gut" feeling. My solution 
was to run a #4 wire from the top joint all the way down to the bottom 
joint on each leg, a "parallel" run across all the joints. I have no 
data to suggest an improvement was made other than to my comfort level!

GL with the project and GL this winter!

73 Joel W5ZN


On 2020-08-19 14:03, Ron WV4P wrote:
> Thanks for all the replies and willingness to share hard earned wisdom.
> 
> Tim, When you say "May cause noise" Is that on TX ? or ?
> I am setting the antenna up to run the 4 parasitic elements like yours, 
> but
> it will be phase 2 as the radials for them elements will be tricky on 
> my
> very unlevel terrain.
> 
> Frank, I do anticipate the use of an inband station although it's not
> likely to be utilized much I would not think.  All RX will be on a mix 
> of
> Beverages, rx vertical arrays and loops 700 - 1200 foot from the TX 
> tower.
> 
> I am a welder, but I can't foresee any safe / reliable way of attaching
> anything to Rohn 25. Maybe putting lugs on each of the 5/16 bolts and
> running an unbroken #6 copper up each leg and bonding together at the 
> top.
> A lot of effort for a likely minimal if any change in scores though.
> 
> Ron, WV4P
> 
> 
> 
> 
> On Wed, 19 Aug 2020 at 03:56, Mail 10 <mail10 at barefoothorse.com.au> 
> wrote:
> 
>> I am planning a similar installation, using Deeco mast sections (6' x
>> 10"). I have 20 of these, used of course. I don't think they have been
>> manufactured for decades. Sections interface with pin and socket, with 
>> 3
>> x 1/2" bolts between plates on each end.
>> 
>> Will also be strapping across the joints, as I know what a PITA
>> intermittent connections are.
>> 
>> It will be a radiating mast with no other antennas on top, apart from 
>> a
>> parallel wire for 80 m operation.
>> 
>> Erection won't commence until at least later in Spring, as the ground 
>> is
>> just so wet now, after one of the wettest years we've had.
>> 
>> 73, Luke VK3HJ
>> 
>> On 19/08/2020 4:06 am, Ron WV4P wrote:
>> > Howdy All,
>> >
>> > I'm getting ready to put up a Rohn 25 Insulated Base ~1/4 wave vertical.
>> > (115') and I'd like to get some advice if possible.
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