Hi Bill,
Well, I have one of those in my barn hanging over the workbench. It has a
coat hanger wire coming down from each of the four mounting holes. Its real
easy to get the correct angle to provide the 50 ohm fed point impedance. I
also have a Diskcone in the attic that covers 144/223/440. They both use the
same principal as far as the skirt is concerned. You adjust the skirt angle
to obtain the desired feed impedance.
I suspect the WWV antenna is a little more sceintific, but the same
principal should apply.
* 73's Jim W5IFP *
>-----Original Message-----
>From: Bill Aycock [mailto:billaycock@centurytel.net]
>Sent: Monday, April 06, 2009 14:38
>To: Jim Hargrave; Towertalk
>Subject: Re: [TowerTalk] Vertical vs Beam
>
>
>Jim
>I have used that type. In fact-- my first non-ducky 2M antenna
>was made on
>an SO238 panel mount, hung from the ceiling light fixture in the shack.
>However there is confusion about the difference between what we,
>individually, do, and what the WWV setup is.
>I would like to know, just as I would like to know the real
>description of
>the claimants on TT. I know there is confusion about the use of
>a radial
>system, and I suspect the location of the feedpoint is the key.
>Bill-W4BSG
>
>----- Original Message -----
>From: "Jim Hargrave" <w5ifp@gvtc.com>
>To: "Towertalk" <towertalk@contesting.com>
>Sent: Monday, April 06, 2009 9:09 AM
>Subject: Re: [TowerTalk] Vertical vs Beam
>
>
>> Bill,
>>
>> I have used this type antenna for several years. It is a very common
>> VHF/UHF
>> antenna because of its simplicity. It makes a great 17 meter
>antenna and
>> is
>> easy to construct without a lot of real estate.
>>
>> I offer further comment embedded below:
>>
>> >-----Original Message-----
>> >From: towertalk-bounces@contesting.com
>> >[mailto:towertalk-bounces@contesting.com]On Behalf Of Bill Aycock
>> >Sent: Monday, April 06, 2009 13:37
>> >To: Michael Tope; N7mal
>> >Cc: towertalk@contesting.com; John Geiger; Robert Redmon
>> >Subject: Re: [TowerTalk] Vertical vs Beam
>> >
>> >
>> >As far as the subject of 1/2 wave verticals goes, the WWV site
>> >leaves out a
>> >LOT!
>> >1. Where is the feed point?
>>
>> Feed point is at the top of the skirt and the base of the 1/4 wave
>> vertical
>> on top.
>> Coax shield to skirt and center to top vertical.
>>
>> >2. what is the feed point impedance?
>>
>> Nominal 50 ohm. This is accomplished by the angle of the skirt to the
>> driven
>> element.
>>
>> >3. Are the lower ends of the "guys" grounded?
>>
>> Nope. They should have insulators at the 1/4 wave point. The
>more skirt
>> wires you install the more uniform the radiation pattern.
>>
>> >4. Why is it important that the Coax feeds do not cross?
>>
>> Good question. That one is above my pay grade.
>>
>> * 73's Jim W5IFP *
>>
>>
>> >Does anyone know?
>> >Are the arrangements of the TTers with 1/2 wave verticals like
>> >WWV, and if
>> >not, why reference it?
>> >Bill--W4BSG
>> >
>> >
>> > ----- Original Message -----
>> >From: "Michael Tope" <W4EF@dellroy.com>
>> >To: "N7mal" <n7mal@citlink.net>
>> >>
>> >>>----- Original Message -----
>> >>>From: N7mal
>> >>>To: John Geiger ; towertalk@contesting.com
>> >>>>>
>> >> WWV uses 1/2 wave verticals:
>> >>
>> >> http://tf.nist.gov/timefreq/stations/wwv.html
>> >>
>> >>
>> >
>> >
>> >_______________________________________________
>> >
>> >
>> >
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>>
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>>
>>
>>
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>>
>
>
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