It's called "Balanced Capacitive Matching" and is described on Mosley's
web site. Scroll down the following page and look for the Classic Feed
System:
http://www.mosley-electronics.com/page%20files/faq.htm
73,
Bill - W9NHQ
----- Original Message -----
From: "Bill" <w7vp@comcast.net>
To: "Peter Voelpel" <df3kv@t-online.de>; "'Towertalk'"
<towertalk@contesting.com>
Sent: Tuesday, August 15, 2006 9:06 AM
Subject: Re: [TowerTalk] TA-33 Classic Feed Model TAC-33K
> Well it is not a T-match, Pete. A T-match does not have a split
> driven
> element and th ends are indeed attached tot he driven element.
> Doesn't
> sound like a Beta match either since there is no direct coupling to
> the
> elements using inductance to match the feedpoint reactance. Sounds
> more
> like a means of reactively coupling to the the elements with primarliy
> capacitive coupling since the coax center conductor is inside the
> driven
> element. The design of the coupling would naturally take into account
> the
> feedpoint impedance R-jX (or in this case perhaps R+jX) in a fashion
> that
> the R is the characteristic impedance of the coax and the jX is the
> required
> matchin reactance. Neat idea.
>
> 73
> Bill
> W7VP
>
> ----- Original Message -----
> From: "Peter Voelpel" <df3kv@t-online.de>
> To: "'Towertalk'" <towertalk@contesting.com>
> Sent: Tuesday, August 15, 2006 6:53 AM
> Subject: Re: [TowerTalk] TA-33 Classic Feed Model TAC-33K
>
>
>> Hi Dave,
>>
>> To me that sounds more like a T-match
>>
>> 73
>> Peter
>>
>> -----Original Message-----
>> From: towertalk-bounces@contesting.com
>> [mailto:towertalk-bounces@contesting.com] On Behalf Of WA3GIN @
>> Arlington
>> County, VA
>>
>> Hi folks,
>>
>> Just received a new TA-33M with TAC-33K feed.
>>
>> I've never seen a driven element feed like this one. Its a clever
>> implementation. Where the two ends of the driven element converge at
>> the
>> boom a hollow insulated coupling is provided so that the two sections
>> slip into the insulator, making the connection water resistent and
>> eliminating the need to split the feed-line coax wand weather proof
>> the
>> coax shield, etc. In the middle of the insulator is an SO-239
>> connection. Inside the insulator there are two pieces of coax (I'm
>> guessing RG8) center conductor (shield removed but insulation
>> remaining
>> with the ends swrink wrapped) that are simply slid inside each end of
>> the driven element. That is it. No direct connection to the
>> elements.
>> I'm guessing this is Mosley's version of a "BETA" matching system.
>>
>> Any thoughts on this technique or clarification as to whether this is
>> indeed a "BETA" match?
>>
>> 73,
>> dave
>> wa3gin
>>
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