Colin:
A dipole is simply a resonant doublet. The doublet is the generic name for
the antenna.
i use the 88 foot variety quite successfully with the icom ic-703+.
----- Original Message -----
From: "Colin McDonald" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Monday, September 29, 2008 4:50 PM
Subject: Re: Portable or restricted space antenna
> Great project.
> looks like an interesting antenna. The description of how to build it is
> a
> little hard to understand at first, but i think I got the jist.
> I did have to google it, until i looked at the link you posted and
> realized
> there was a space between the last dot and the HTM which made the link in
> operaable.
> Here is the link that will go to the page directly:
>
> HTTP://www.norcalqrp.org/norcaldoublet.htm
>
> looks like there are some other interesting projects on that page as well.
> I'm wondering if someone could explain how or why a doublet works, and
> what
> the difference between a doublet and a regular center fed dipole is.
> I think the computer cable doublet is built like this:
> 50FT of four conducter flat computer cable/ribbon. The two outside wires
> are stripped back 22 feet on each side. The two center wires are cut off
> at
> 30FT from the shack end and shorted together. You use this shorted end to
> support the doublet through a fishing swivel onto a 24 foot fishing poll.
> the other two ends of the previously stripped down 22 foot lengths are
> then
> supported somewhere else away from the central support...although the
> description didn't specify in what sort of configuration they should be
> in,
> either inverted V, V, flat, sloaped, L or what, or perhaps it doesn't
> matter. You then use the two outside wires of the computer ribbon in the
> shack to feed the antenna through an antenna tuner or some kind of
> matching
> network...this is the only downside of the antenna i can see. Apparently
> a
> balun works well for it too.
> anyway, I think that is how it is done.
> Still requires somewhat of a yard to string the longer wires out in some
> kind of configuration to radiate.
> That said, I think this might be a pretty decent antenna for Shaun to try
> out in his circumstances...it sounds very cheap to make, easy to
> physically
> build, and you can likely get away with running the elements in nearly any
> configuration you want to try.
>
> 73
> Colin, V A6BKX
> ----- Original Message -----
> From: "Gale Conard" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Monday, September 29, 2008 8:00 AM
> Subject: Portable or restricted space antenna
>
>
>>
>> I don't think I have noticed any mention of this antenna, in all the
> antenna
>> discussions on the list.
>>
>> For those of _us! who have very little space, it might be worthwhile
> looking
>> at the NorCal doublet. I haven't tried it, yet, but I plan to as soon as
> I
>> can gather the materials. I can think of no reason why it shouldn't work
> as
>> well with 100 watts as with QRP. With minor modifications, it would
>> probably be ok for higher power, too.
>>
>> The website is:
>> http://norcalqrp.org/norcaldoublet.
>> htm
>>
>> or, I found it with Google.
>>
>> Good luck and have fun.
>>
>> 73,
>> Gale
>> [log in to unmask]
>>
>>
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