latter line has coated or otherwise insulated wire right? usually enameled?
Or is it bear copper?
73
Colin, V A6BKX
----- Original Message -----
From: "Ian Westerland" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Friday, May 03, 2013 7:19 AM
Subject: Re: Doublet Antenna
>I have never used ladder line until this project and part of the
> issue with it, particularly the 300 Ohm line is that it can be quite
> fragiel. At present it is neatly spread out, some of it inside and
> the rest outside my shack window. One of the articles I read was
> from a very happy doublet user who said he had his excess ladder line
> coiled up in his shack without affecting the performance of the
> aerial. One of the main challenges in using balanced line feed is
> that the length is critical moreso than the actual lengths of the
> aerial elements. The doublet is often referred to as an "Antenna
> system" because of the feed system being part of the aerial itself.
>
> Today i have had contacts on 20 40 and 80 meters which is a vast
> improvement from earlier this week when I could only talk on 80.
>
> 73
>
>
> Ian, VK3vin
>
>
>
> At 08:57 PM 3/05/2013, you wrote:
>>Ed,I would appreciate you and the other guys on the list that use ladder
>>line tellling me what you do with the excess ladder line. I have tried
>>using ladder line several times but without success and I blame my
>>ignorance on this. My tower is only about 40 feet high and is right
>>outside my radioshack window and this leaves me about 55 feet of excess
>>ladder line. I never knew what to do with this. Thanks much,
>>
>>-----Original Message-----
>>From: For blind ham radio operators [mailto:[log in to unmask]]
>>On Behalf Of Ed Malmgren
>>Sent: Thursday, May 02, 2013 11:45 PM
>>To: [log in to unmask]
>>Subject: Re: Doublet Antenna
>>
>>Hello Ian, Perhaps you know this but if you twist your feedline about one
>>turn every 0.5 meters the wind will not blow it around so much. I have
>>built probably ten dipoles over the years and good luck. 73
>>Ed K7UC
>>
>>--------------------------------------------------
>>From: "Ian Westerland" <[log in to unmask]>
>>Sent: Thursday, May 02, 2013 9:11 PM
>>To: <[log in to unmask]>
>>Subject: Re: Doublet Antenna
>>
>> > Hi Colin. It is a centre fed di pole with open wire feed line instead
>> > of coax. So you have the centre insulator witht the 2 wires which you
>> > can have as a flat top or inverted v. The length depends on what you
>> > want and how much space you have to fit it in.
>> >
>> > Mine is an inverted v configuration cut for 3.58 Megahertz
>> > 65.4 feet long, or 19.92 meters.
>> >
>> > The feed line which is the tricky part of the aerial is 30.4 meters or
>> > 102 feet long hanging down as close as possible to 90 degrees from the
>> > wires.
>> >
>> > This comes down to a 4:1 balun, into about 1 meter of RG-213 coax into
>> > the LDG KT-100 tuner.
>> >
>> > There is a lot of interesting and helpful information on the internet
>> > if you type into your search engine, "Doublet antenna" including a
>> > very helpful chart with recommended feed line lengths for 80 and 40
>> > meters. It also shows how some lengths of feed line are to be
>> > avoided. The recommended feed line lengths are in green and the ones
>> > to be avoided are in red.
>> >
>> > Hope that helps. Stay in touch and hopefully we will have a QSO one
>> > day. I hear some good signals from Canada regularly at night.
>> >
>> >
>> > 73
>> >
>> >
>> > Ian, VK3vin
>> >
>> >
>> >
>> > At 12:49 PM 3/05/2013, you wrote:
>> >>can you describe the basic design and construction of the antenna?
>> >>IE element length and feedline length?
>> >>I've never experimented with a doubllet style and wouldn't mind trying
>>it.
>> >>
>> >>73
>> >>Colin, V A6BKX
>> >>----- Original Message -----
>> >>From: "Ian Westerland" <[log in to unmask]>
>> >>To: <[log in to unmask]>
>> >>Sent: Thursday, May 02, 2013 8:28 PM
>> >>Subject: Doublet Antenna
>> >>
>> >>
>> >> > Hello to all on the list. Someone posted a question about doublet
>> >> > antennas a couple of days ago and i have just made one for multi
>> >> > band operation between 80 and 10 meters. It has been a challenge
>> >> > but the results so far are really better than I thought they would
>> >> > be.
>> >> >
>> >> > The antenna is cut for a low frequency of 3.58 megahertz in our 80
>> >> > meter band, fed with 300 Ohm feed line, through a 4:1 balun into an
>> >> > LDG TK-100 tuner. The results on 80 meters are the best I have had
>> >> > from any antenna used so far including the standard coaxial fed
>> >> > dipole although there seems no real reason why this should be the
>> >> > case. Maybe it is the lower loss feed line doing the job.
>> >> >
>> >> > I have encountered problems on 40 meters that seem to be related to
>> >> > the length of the feed line but results are improving with a little
>> >> > fine tuning and experimentation with feed line length. The doublet
>> >> > is 9 meteres off the ground at present, but during next week it
>> >> > will be raised by another 3 meters so it will be 12 meters or 40
>> >> > feet at its apex.
>> >> >
>> >> > I will post to the list again on the doublet when I complete the
>> >> > project but at present, even though it is not at its optimum, I am
>> >> > more than happy with its performance on both transmit and receive.
>> >> >
>> >> > Ian Westerland, VK3vin
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