I did not think that a static drain would help precipitation static but I was
curious what experiences others have had. It would be nice if it really was
that simple. Below is what w8JI wrote on the subject:
"Despite having grounded antennas and the same rain or precipitation striking
physically identical antennas, the highest antennas are always noisy and the
lowest antennas are always the quietest. This occurs on a variety of antennas
and in a variety of systems. Antennas with grounded elements and antennas with
insulated elements all behave in similar ways. Antennas near the top of towers,
especially those without taller towers nearby, all have severe p-static in
storms. Lower antennas show very little noise under the same conditions, even
though they are being struck by the same particles.
The cause of noise most commonly called p-static or precipitation static is
obviously not from charged particles striking the antenna. While some of this
might occur under some conditions, the overwhelming cause appears to be corona
discharge from protruding points into space around the antennas or antenna
structures. On dark nights with closing storms, I can look at my upper 40-meter
Yagi with binoculars and see a faint
http://en.wikipedia.org/wiki/St._Elmo's_fire from the element tips. This is
similar to what I saw on the VHF antenna that noised-up during foul weather.
Sailors have seen it on salt-water soaked wooden masts, and we are plagued by
it also. We just have not paid enough attention to the evidence and have missed
the real root cause. We consider it particles striking the antenna was nearly
all cases appear to be the simple phenomena known as St. Elmo's fire.
We can't cure precipitation static, but it can be reduced through the following
steps:
• Having something else much taller than the receiving antenna close to the
receiving antenna or lowering antenna height.
• Avoiding sharp points on or near the antenna. Sharp points increase voltage
gradient and increase corona.
• Avoiding protruding elements. Protruding elements increase corona.
As a general rule the following makes little difference:
• Grounded elements
• DC shunt elements on feed lines
• Improving ground systems or grounding"
John KK9A
From: ve6wz@shaw.ca <ve6wz@shaw.ca>
Sent: Tuesday, December 16, 2025 8:58 PM
To: john@kk9a.com; Jack Brindle <jackbrindle@me.com>
Cc: towertalk@contesting.com
Subject: Re: [TowerTalk] Static Drain Resistor in Arrestor
Jack,
"P-Static" (precipitation static) is a different phenomena that "wind static".
A grounded antenna will NOT prevent P-Static. W8JI is correct.
Wind static can build incredible voltages (I've seen it) and will discharge to
ground. Grounding the element through a choke or high value resistor will
eliminate this. All my antennas must have this.
Precipitation static is a different thing. This is that screeching, buzzing,
even whistling sound that will crescendo and sputter out, only to start again.
Its the noise that when happening will shut you down from operating.
It happens when a storm is approaching or in effect. I hear it all the time
during rainstorms and even snowstorms.
Grounding the elements on your Yagi or verticals make NO difference at all to
this type of static.
I really don't think precipitation static is well understood regarding how it
develops and the exact mechanism that triggers it, but a google search might
give you some background.
Either way, a static drain choke or resistor will NOT eliminate this type of
noise when it happens.
Steve ve6wz
________________________________________
From: TowerTalk <mailto:towertalk-bounces@contesting.com> on behalf of Jack
Brindle via TowerTalk <mailto:towertalk@contesting.com>
Sent: Tuesday, December 16, 2025 4:06 PM
To: mailto:john@kk9a.com <mailto:john@kk9a.com>
Cc: mailto:towertalk@contesting.com <mailto:towertalk@contesting.com>
Subject: Re: [TowerTalk] Static Drain Resistor in Arrestor
Yes, it definitely helps with rain static. If W8JI actually stated that
grounding the elements doesn’t help, he was wrong.
It is important to bring both sides to ground, and together, usually through a
large value resistor or RF Choke that will handle the power. Tieing both sides
of a dipole through this to ground provides a path to bleed off the static
charge, thus eliminating rain static (and snow static, etc). As Wes stated,
adding a fairly large resistor across the dipole insulator really helps. Then
timing that to ground through the arrestor finished the job.
73,
Jack, W6FB
> On Dec 16, 2025, at 5:48 PM, mailto:john@kk9a.com wrote:
>
> Does the Morgan coaxal arrestor help with precipitation static or just the
> arc noise? Rain static can be brutal when contesting. I thought mine might
> be related to using OWA designs with insulated elements but W8JI has stated
> that grounded elements make little difference.
>
> John KK9A
>
> Ron WV4P wrote;
>
> My fullsize 4el 40 with cool dry air wil arc several inches from coax tip
> to ground from static. With the Morgan M303 inline... Nothing. This was
> also very apparent on the SDR (Flex) screen from what looked like lightning
> static crashes to.. Nothing. In that respect, they did exactly what they
> claimed.
>
> Ron, WV4P
>
>
> _______________________________________________
>
>
>
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