Further to my previous

Traps can be unreliable if they aren't properly encapsulated.

I have a g8kw trap dipole (similar to the w3dzz) which I have had for 35 years and often used in temporary situations.
Originally it was fed with 75 ohm coax, now with 75 ohm twin into a 1 to 1 balun.
As mentioned previously, it doesn't resonate on the WARC bands, but can be tuned through an ATU.

Radiation against resonance!

As much resonant wire or metal as high as possible is the key, but we are here talking about a field situation.

73

Atb


David W Wood

Ham call - G3YXX
FOC # - 1685
Licensed - 1969
 

-----Original Message-----
From: For blind ham radio operators [mailto:[log in to unmask]] On Behalf Of Steve Forst
Sent: Wednesday, May 30, 2012 10:51 PM
To: [log in to unmask]
Subject: Re: looking for a 10-80M trapped dipole

Colin,

A few of the more popular companies for loaded dipoles are: Alpha Delta, 
Hy Power, and Spi Ro.  Maybe some searches here will kick up something.

Anything loaded for 80 meters is going to  have  a serious limitation on 
usable bandwidth without a tuner.   But if he has a favorite band 
segment, it could be tuned for that portion of the band.

Parallel dipoles  can give a number of bands without a tuner,or traps, 
but  adding more wires  may make it  hard to put up and down multiple times.

Another option would be an off center fed (Windom type) antenna.  Multi 
bands, no traps and  possibly only some need for a tuner at the high end 
of 75 meters.   Maybe too long, at 136 ft for 80 through 6 meters.  Also 
no resonance on 30 or 15.   A 40 meter OFC is about 66 ft. long  and of 
course won't cover 80/75 as well as 30 and 15.

73, Steve KW3A

On 5/30/2012 1:56 AM, colin McDonald wrote:
> a friend is looking for a 10 to 80M trapped dipole requiring little or no
> tuner, that can be fairly easily deployed in the field.
> He's already got a tripple hussler arrangement on the RV, and an Icom long
> wire tuner.
> However, he now has a 40FT telescoping linemans poll stuck to the back of
> the RV that can be raised up to support the center of a bigger HF dipole.
> He doesn't really want to go the G5RV route due to the necesity of the
> latter line hanging down...he wants flexibility for various anchoring
> arrangements and easy deployment.
> Does anyone have any recommendations for a good 10M to 80M dipole that might
> fit these requirements?
> As I said, little to no tuning would be best.
> Though he does have a couple small LDG auto tuners that would make life
> simpler if the antenna needed a bit of tuning on the various bands.
> Either a prebuilt antenna, or any recommendations as to where one can
> perchase premade traps that can be used to build such a beast.
>
> 73
> Colin, V A6BKX
>
>
>

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