[TowerTalk] Quad vs SteppIR
david jordan
wa3gin at erols.com
Mon Aug 30 13:50:29 EDT 2004
clarify please...
Noise from point source such as a tower or building and percepitation
static created when dropplets of rain or snow flakes that are charged
come in contact with the elements of a bare wire or beam antenna.
When pointing a low antenna at a tall tower is the direction of the
storm front also in the same direction as the tall tower? Is the noise
increase due to a local noise source like the taller tower or is the low
beam pointing into the noise source behind it or are you hearing two
separate noise sources?
In the winter I can hear an approaching snow storm on my 160m dipole.
Has anyone experienced a storm front in the winter listening on a beam
and then turned the beam away from the approaching front and heard the
noise floor drop?
My experience is there are several noise source scenarios. The storm
front which could be at a distance and approaching (not local
percepitation static), the combination of the local static due to
charged rain drops or snow flakes as well as the mass of the storm
moving in the direction the beam is facing, and the third being the
local static produced by the charged rain drops and snow flakes on the
beam and other objects in the vicinity of the beam.
I've heard the distant noise of an approaching snow storm and the
distinct pops due to descrete discharges of drops of rain on the beam
elements. These are very different sounding noise sources. Once the
approaching storm has arrived I've not been able to hear the distinct
discharges because the noise floor is too high to distinguish...
I would think the Stepper would be less suseptible to the distinct
discharge noise from rain drops and snow flakes because the copper
elelments are protected from the charged particles by the fiberglass
tubing, but would have no benefit from the noise produced by an
approaching storm front or noise while in the mist of a storm.
I've enjoyed using loop antennas in part because they appear to me to be
less suseptible to man-made noise, esp. when fed with shielded twin lead
to reduce common mode noise from long vertical runs of single coax feds.
The question is really whether these noise sources prevent us from
hearing that DX station we're tried to work for the past 3 years!
73,
dave
wa3gin
kk9a at arrl.net wrote:
>There are times during storms that my upper antennas have heavy static and
>the lower ones are much quieter. Perhaps your antenna is low and less prone
>to static than your buddies?
>
>John KK9A
>
>
>----- Original Message -----
>From: "Richard M. Gillingham" <rmoodyg at bellsouth.net>
>To: <N2TK at arrl.net>; "'Tom Rauch'" <w8ji at contesting.com>;
><towertalk at contesting.com>; "'Bill Ogden'" <ogden at us.ibm.com>
>Sent: Monday, August 30, 2004 15:20
>Subject: Re: [TowerTalk] Quad vs SteppIR
>
>
>I can't speak for snow static, living in south Florida, but the steppir is
>less prone to precip static because (I think) of the fact that the elements
>are enclosed in a "radome"... When some of my local buddies are complaining
>of precip static during rain storms, I don't hear it. That's not to say you
>won't hear static crashes from lightning. There's plenty of that down here.
>(grin)
>
>There are certainly more knowledgable folks on here, but that's my
>experience.
>
>Good luck,
>Gil, W1RG
>3el up since Aug 2002.
>
>
>
>----- Original Message -----
>From: "N2TK" <tony.kaz at verizon.net>
>To: "'Tom Rauch'" <w8ji at contesting.com>; <towertalk at contesting.com>; "'Bill
>Ogden'" <ogden at us.ibm.com>
>Sent: Monday, August 30, 2004 11:13 AM
>Subject: RE: [TowerTalk] Quad vs SteppIR
>
>
>
>
>>Hi Tom,
>>
>>When I had a quad and monobanders, the quad was always quieter from snow
>>static than the monobanders. Was wondering if the SteppIR would be quieter
>>than a regualr aluminum beam during a snow storm since the snow would be
>>in
>>contact with fiberglass instead of aluminum? Or would the static charge be
>>the same regardless of material?
>>Tnx
>>N2TK, Tony
>>
>>-----Original Message-----
>>From: towertalk-bounces at contesting.com
>>[mailto:towertalk-bounces at contesting.com] On Behalf Of Tom Rauch
>>Sent: Monday, August 30, 2004 10:54 AM
>>To: towertalk at contesting.com; Bill Ogden
>>Subject: Re: [TowerTalk] Quad vs SteppIR
>>
>>
>>
>>>I am wondering if a 3 element SteppIR would provide any
>>>
>>>
>>noticable
>>
>>
>>>improvements in my situation. The SteppIR is probably
>>>
>>>
>>easier to handle and
>>
>>
>>>the 180 degree switch appears to be a very nice feature,
>>>
>>>
>>but is this
>>
>>
>>>sufficient to justify switching? Does anyone have
>>>
>>>
>>experiences about quad
>>
>>
>>>vs SteppIR?
>>>
>>>
>>Hi Bill,
>>
>>This is all based on "how it works" data, not an actual comparison. I've
>>had
>>quads and Yagis, and the SteppIR is nothing but a Yagi.
>>
>>If both your old quad and the proposed SteppIR antennas both have
>>reasonable
>>efficiency, you can expect performance to be roughly proportional to boom
>>length, assuming the number of elements is nearly optimum for any given
>>boom
>>length. This means the SteppIR should at least equal if not actually
>>improve
>>performance as long as it has a longer boom. My bet is that it would
>>actually improve your system a few dB for both receiving and transmitting.
>>
>>I almost hate to say this, but an occasional reminder is due from time to
>>time. A quad has no real gain advantage over a similar size Yagi. The
>>original "2dB" thing came from flawed measurements of a scaled model by a
>>W2
>>and W6 long ago, and once it was in print that was it...it took on a life
>>of
>>its own. At some heights a small quad antenna can show a little advantage
>>(perhaps 1 dB) and at other heights a slight loss over a similar boom
>>length
>>yagi. Overall they are about equal, although for some reason long quads
>>did
>>not fair well in actual measurements (Wayne Overbeck N6NB and Dave Bell
>>W6AQ, CQ Magazine, May 1982).
>>
>>Another quad myth is capture area, but physical aperture is not the same
>>as
>>electrical aperture or "capture area".
>>Capture area only relates to gain and frequency, so any antenna with the
>>same gain on the same frequency has the same capture area! That's true if
>>one is a big box, and the other is a small single plane element. Capture
>>area also does not determine S/N ratio, so it a moot point anyway.
>>
>>Directivity sets receiving, not gain or capture area (more correctly
>>called
>>effective aperture). I would expect the SteppIR to receive better, because
>>it should have better directivity. The exception might be in times of
>>inclement weather, since the quad generally has less of a corona
>>(P-static) problem. In the few quads I've had here, that was the only
>>advantage I ever saw when comparing them to similar size Yagi's.
>>
>>73 Tom
>>
>>
>>_______________________________________________
>>
>>See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
>>Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
>>any
>>questions and ask for Sherman, W2FLA.
>>
>>_______________________________________________
>>TowerTalk mailing list
>>TowerTalk at contesting.com
>>http://lists.contesting.com/mailman/listinfo/towertalk
>>
>>
>>_______________________________________________
>>
>>See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
>>Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
>>any questions and ask for Sherman, W2FLA.
>>
>>_______________________________________________
>>TowerTalk mailing list
>>TowerTalk at contesting.com
>>http://lists.contesting.com/mailman/listinfo/towertalk
>>
>>
>
>_______________________________________________
>
>See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
>Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
>questions and ask for Sherman, W2FLA.
>
>_______________________________________________
>TowerTalk mailing list
>TowerTalk at contesting.com
>http://lists.contesting.com/mailman/listinfo/towertalk
>
>
>
>_______________________________________________
>
>See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions and ask for Sherman, W2FLA.
>
>_______________________________________________
>TowerTalk mailing list
>TowerTalk at contesting.com
>http://lists.contesting.com/mailman/listinfo/towertalk
>
>
>
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