[TowerTalk] Broadbanding 80 meter dipole

[Roger (K8RI) on TT]

Mounted on the tower would put the tuners about 75 to80 feet from the 
feed points and although center fed they are a LONG way from being 
balanced, requiring 2 common mode chokes to keep RF out of the shack on 75.

73, Roger (K8RI)

On 8/17/2017 Thursday 8:17 PM, Steve Maki wrote:
> If the tuner(s) are mounted on the tower.
>
> -Steve K8LX
>
> On 8/17/2017 7:53 PM, Steve Maki wrote:
>> Except Roger is envisioning sloping *dipoles*, FIVE of them. Somehow 
>> I can't picture five tuners hanging out there in mid-air at the 
>> feedpoints, begging to be tuned up and down the band. Not to mention 
>> that whatever pattern he's hoping for will be hopelessly compromised 
>> by common mode currents on the feedlines between the antenna and tuner.
>>
>> -Steve K8LX
>>
>> On 8/17/2017 4:16 PM, Kimberly Elmore wrote:
>>
>>> Rod's idea is by far the best. Slopers are weird creatures. While 
>>> you can broadband antennas by making the elements with a large 
>>> diameter (as in a cage) the mechanical complexity isn't worth it. If 
>>> they absolutely positively must be resonant, well...
>>>
>>> Kim N5OP
>>>
>>>        From: Rod Greene via TowerTalk <towertalk at contesting.com>
>>>   To: Roger (K8RI) on TT <K8RI-on-TowerTalk at tm.net>; 
>>> "towertalk at contesting.com" <towertalk at contesting.com>
>>>   Sent: Thursday, August 17, 2017 2:25 PM
>>>   Subject: Re: [TowerTalk] Broadbanding 80 meter dipole
>>> Or use an auto tuner at the feedpoint to match the slopers on 
>>> whatever band/freq you want to use. That's what I do.
>>> 73, Rod/w7zrc
>>>
>>>
>>>        From: Roger (K8RI) on TT <K8RI-on-TowerTalk at tm.net>
>>>   To: "towertalk at contesting.com" <towertalk at contesting.com>
>>>   Sent: Thursday, August 17, 2017 12:33 PM
>>>   Subject: [TowerTalk] Broadbanding 80 meter dipole
>>> I've seen a few possibilities in the past, but I'd like to add a dew
>>> slopers to come up with the 5 used for some directivity, gain and front
>>> to back. Switched coils at the feedpoint with frequency sensing would
>>> likely work.  I've had excellent results with just a couple switched
>>> slopers on 40.
>>>
>>> To complicate things I'd like to do this and maintain the dual band 
>>> 75 /
>>> 40 meter operation, which would likely require separate feedlines. The
>>> unused line would / could end up as a stub.  I could possibly use the
>>> frequency sensing to disconnect the coax for the unused band.
>>>
>>> Thoughts?
>>>
>>
>> _______________________________________________
>>
>>
>>
>> _______________________________________________
>> TowerTalk mailing list
>> TowerTalk at contesting.com
>> http://lists.contesting.com/mailman/listinfo/towertalk
>
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk at contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk


-- 

73

Roger (K8RI)


---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus