Gary Schafer wrote:
> A vertical above your beam will not work. An elevated vertical must have
> resonant radials.
>
Most won't, but the AV640 and the MFJ/Cushcraft verticals will although
the AV640 needs to be at least 5' above the beam while MFJ says 10' for
theirs. That is one whale of a lot of leverage to exert on the top of
that tower what with both versions being on the order of 30' tall (more
or less) and although they are advertised as not needing guys, they do
recommend them and particularly at that kind of height.
I will be mounting the AV640, or one of the Cushcrafts above my
tribander when I get it moved from the 100' 45G to the 50' 25G.
73
Roger (K8RI)
> 73
> Gary K4FMX
>
>
>> -----Original Message-----
>> From: towertalk-bounces@contesting.com [mailto:towertalk-
>> bounces@contesting.com] On Behalf Of AD5VJ Bob
>> Sent: Wednesday, October 21, 2009 9:49 PM
>> To: towertalk@contesting.com
>> Subject: Re: [TowerTalk] Ground mounting vs roof mounting verticals
>>
>> Interesting,
>>
>> I was just thinking of taking my Butternut vertical off the ground and
>> mounting it to the top of my mast above my Hornet Tribander
>> at around 35 feet.
>>
>> So far it sounds like it might just be worth it.
>>
>> My question would be how would I attach radials to the base of the
>> vertical like that when my rotor is turning the mast?
>>
>> Would the tower be ground enough by itself to make the other half of the
>> vertical or could it work off of the tribander for its
>> ground and not use wire radials??
>>
>> Bob AD5VJ
>>
>>
>>> -----Original Message-----
>>> From: towertalk-bounces@contesting.com
>>> [mailto:towertalk-bounces@contesting.com] On Behalf Of Steve Katz
>>> Sent: Wednesday, October 21, 2009 8:48 PM
>>> To: Jon; ve3zi@rac.ca; towertalk@contesting.com
>>> Subject: Re: [TowerTalk] Ground mounting vs roof mounting verticals
>>>
>>> My experience is closer to W4ZWs. My 6BTV at 28' with 24
>>> radials is comparable to my inverted vees at 55 feet, and
>>> typically 6 dB down from my beams on 15 & 20 meters at 60'.
>>> Moving it to the ground with 105 radials isn't anywhere near as good.
>>>
>>> WB2WIK/6
>>>
>>> ________________________________
>>>
>>> From: towertalk-bounces@contesting.com on behalf of Jon
>>> Sent: Mon 10/19/2009 6:47 PM
>>> To: ve3zi@rac.ca; towertalk@contesting.com
>>> Subject: Re: [TowerTalk] Ground mounting vs roof mounting verticals
>>>
>>>
>>>
>>> My mileage did indeed vary.
>>>
>>> I had an old 14AVQ mounted as a ground-plane up about 35' and
>>> it was a killer DX antenna, not as good as my TH-6DXX at 75'
>>> but very good as a second antenna. I later mounted it on the
>>> ground and it lost a lot compared to the TH-6DXX.
>>>
>>> As a GP on 40M it was a great antenna for DX work. On the
>>> ground, it was less than a dipole at 50'.
>>>
>>> As you said YMMV
>>>
>>>
>>>
>>> Jon Hamlet, W4ZW
>>>
>>> Casey Key Island, Florida
>>> "A little piece of paradise in the Gulf of Mexico"
>>>
>>>
>>>
>>>
>>> ---Original Message-----
>>>
>>>> From: towertalk-bounces@contesting.com
>>>>
>>> [mailto:towertalk-bounces@contesting.com]
>>>
>>>> On Behalf Of Roger Parsons
>>>> Sent: Monday, October 19, 2009 5:46 PM
>>>> To: towertalk@contesting.com
>>>> Subject: Re: [TowerTalk] Ground mounting vs roof mounting verticals
>>>>
>>>> I have an old AV3 10-15-20m vertical. I used to have it on
>>>>
>>> top of a 20'
>>> pole with 4 radials
>>>
>>>> for each band. Compared to my A4S it was so bad as to be useless -
>>>>
>>> although the match
>>>
>>>> was good on every band.
>>>>
>>>> I moved it to ground level with a lot of radials. It is now
>>>>
>>> about 6dB
>>> worse than the beam
>>>
>>>> which makes it a useful second antenna.
>>>>
>>>> YMMV
>>>>
>>>> 73 Roger
>>>> VE3ZI
>>>>
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>>
>>>>
>>>>
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>>>>
>>> 06:40:00
>>>
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