Hi Tom -
I really don't think you should try that unless you are prepared to go
through a complete retunning exercise. As Jim pointed out the wire and the
tubing are different diameters and that will affect things, Also the TH-7
gets it's broadband characteristics by having two drivren elements. They are
tied together and they are each different lengths and both are different
lengths than the TH-6DXX driven element. So you're getting into a real can
of worms. Just clean things up, including the element overlaps, trap
connections and all driven element connections and you should be fine. I did
this to an old TH-6DXX a few years ago and have been quite impressed with
the way it plays. Good Luck !
Gene / W2LU
----- Original Message -----
From: "Jim W7RY" <jimw7ry@gmail.com>
To: "Tom_N2SR" <tom_n2sr@yahoo.com>; <towertalk@contesting.com>
Sent: Sunday, September 25, 2011 4:46 PM
Subject: Re: [TowerTalk] TH6DXX matching/beta tubes question
>I would leave it alone. It's worked for years like that!
> If you did as suggested, the diameter of the tubes vs. the wire would come
> into play. It would not be a one-for-one exchange.
>
>
>
> 73
> Jim W7RY
>
>
> --------------------------------------------------
> From: "Tom_N2SR" <tom_n2sr@yahoo.com>
> Sent: Sunday, September 25, 2011 7:34 AM
> To: <towertalk@contesting.com>
> Subject: [TowerTalk] TH6DXX matching/beta tubes question
>
>>
>>
>> Hello All!
>>
>>
>> I have a TH6DXX that I will be refurbishing soon (and it will be for sale
>> after that).
>>
>> I know there are several versions of this antenna. Mine has the standard
>> beta tubes
>> which terminate into a loop of aluminum wire approximately 12 inches
>> long,
>> which is
>>
>> then grounded to the boom.
>>
>>
>> My question is, could I purchase longer beta tubes, cut them so they
>> would
>> match the
>>
>> length of the current beta tubes + aluminum wire, and then use the same
>> type of beta
>>
>> tube grounding mechanism that is used on the TH7DX antenna?
>>
>> Would that change the feedpoint impedance?
>>
>>
>> Thanks!
>>
>> Tom, N2SR
>> _______________________________________________
>>
>>
>>
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>
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>
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>
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