ah, ok, good to know.
the spi ro antennas sound interesting...as do the others.
thanks for the suggestions.
I'll pass the info along and leave it in his hands...
73
Colin, V A6BKX
----- Original Message -----
From: "Steve Forst" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Wednesday, May 30, 2012 6:50 PM
Subject: Re: looking for a 10-80M trapped dipole
> Colin,
>
> I know the Radio Works guy in Virginia has a line of OCF antennas that
> use part of the feedline to radiate. However, most of the
> "traditional" OCF antennas from Array Soulutions, Hy Power, Buckmaster,
> etc., use standard 50 ohm coax feed to a balun at the feedpoint. The
> balun is either 4, or 6, or 9 to 1 ratio, depending on whose propaganda
> tells you that their version is best.
>
> I'm not aware that Alpha Delta dipoles use ladder line feed. I think it
> is possible to set them up that way, and I think the ones that come with
> a standard center insulator (no balun) have screws to allow open wire
> feed if desired, but the antennas are designed for 50 ohm coax feed.
>
> The loaded dipoles from Spi Ro, use traditional style traps with
> capacitors.
>
> The ones from Alpha Delta and Hy Power use coils of enameled wire on a
> pvc form. The coils act as a high impedance to isolate a portion of
> the antenna for a particular band. I'm sure there are comprimises
> involved here, but no caps to break down, and no sealing or water
> proofing needed.
>
> 73, Steve KW3A
>
>
>
>
> On 5/30/2012 6:28 PM, colin McDonald wrote:
>> looking at the alfa delta's, from what I read, which wasn't a whole lot,
>> they also use latter line as part of the antenna.
>> the off center fed idea is a good one...there are versions that don't
>> utilize the vertical radiator portion.
>> I'll check out david's suggestion as well since wark bands aren't
>> terribly
>> important in this case.
>>
>> 73
>> Colin, V A6BKX
>> ----- Original Message -----
>> From: "Steve Forst"<[log in to unmask]>
>> To:<[log in to unmask]>
>> Sent: Wednesday, May 30, 2012 3:50 PM
>> 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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