[TowerTalk] Isotron Antennas

Sun Mar 1 15:12:13 PST 2009

The consensus on the antenneX antenna discussion lists, and in several 
articles in the magazine (www.antennex.com) is that the Isotron and 
similar devices (the EH, the CFA, etc.) are, at best, a means of 
terminating a coax such that common mode current on the outside of the 
shield of a sufficiently long feed line actually does the radiating. 
Placing a choke balun at the feed point of such devices generally 
reduces their effectiveness to the dummy-load/incandescent light bulb 
performance bracket, confirming that view.

If they are sold as defying the laws of physics, as some are, they're 
snake oil. If you understand from the beginning that you are going to 
rely on feed line radiation to operate such an "antenna" (if you can 
even call it that), and you can meet the installation conditions to make 
that work, AND if it satisfies your needs, go for it.

In other words: Caveat emptor!

73,
Tom, KT9OM

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> Today's Topics:
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>    1. Re: Isotron Antennas (K7LXC at aol.com)
>    2. tall crank-up tower post? (David J Windisch)
>    3. Re: tall crank-up tower post? (Mirko S57AD)
>    4. Re: Isotron Antennas (Bill MacLane)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Sun, 1 Mar 2009 12:15:49 EST
> From: K7LXC at aol.com
> Subject: Re: [TowerTalk] Isotron Antennas
> To: towertalk at contesting.com, n4zr at contesting.com
> Message-ID: <c48.2bb90b7b.36dc1cc5 at aol.com>
> Content-Type: text/plain; charset="US-ASCII"
>
>  
> In a message dated 3/1/2009 8:29:16 A.M. Pacific Standard Time,  
> towertalk-request at contesting.com writes:
>
>   
>>  It is a joke - much less effective than one of the MFJ  compact loop 
>>     
> antennas, or the original compact loop if you can find  one.
> I remember that KA9FOX won Sweepstakes low power one year from  Puerto 
> Rico using one of the originals.
>  
>     Well, the efficiency surely is very low but Tom  Schiller, N6BT, wrote an 
> article a couple of years ago about making QSOs using  a 100W lightbulb for 
> an antenna. Bottom line? Just about anything will radiate  - even a lightbulb 
> and even an Isotron.
>  
> Cheers,
> Steve    K7LXC
> TOWER TECH 
>
>
>
>  
> **************Get a jump start on your taxes. Find a tax professional in your 
> neighborhood today. 
> (http://yellowpages.aol.com/search?query=Tax+Return+Preparation+%26+Filing&ncid=emlcntusyelp00000004)
>
>
> ------------------------------
>
> Message: 2
> Date: Sun, 1 Mar 2009 13:57:25 -0500
> From: "David J Windisch" <davidjw at cinci.rr.com>
> Subject: [TowerTalk] tall crank-up tower post?
> To: <towertalk at contesting.com>
> Message-ID: <1BD1421A88AA4F82A33D61CEEEE4B7CB at DavidJWindisPC>
> Content-Type: text/plain;	charset="iso-8859-1"
>
> Searched unsuccessfully for a post  within the last 2 years (I think) regarding 5 specially-built 100-foot-plus crank-ups with large wind-load capacity fully-extended.  Any help out there, please?
>
> Tia & 73 Dave W8FGX
>
> ------------------------------
>
> Message: 3
> Date: Sun, 01 Mar 2009 20:17:02 +0100
> From: Mirko S57AD <miroslav.sibilja at amis.net>
> Subject: Re: [TowerTalk] tall crank-up tower post?
> To: David J Windisch <davidjw at cinci.rr.com>
> Cc: towertalk at contesting.com
> Message-ID: <49AADF2E.20304 at amis.net>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> You meant Luso towers (www.luso.us)?
>
> 73  Mirko, S57AD
> David J Windisch pravi:
>   
>> Searched unsuccessfully for a post  within the last 2 years (I think) regarding 5 specially-built 100-foot-plus crank-ups with large wind-load capacity fully-extended.  Any help out there, please?
>>
>> Tia & 73 Dave W8FGX
>> _______________________________________________
>>
>>
>>
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>>   
>>     
>
>
> ------------------------------
>
> Message: 4
> Date: Sun, 1 Mar 2009 11:45:58 -0800 (PST)
> From: Bill MacLane <ai4wm at yahoo.com>
> Subject: Re: [TowerTalk] Isotron Antennas
> To: Tower Talk <towertalk at contesting.com>, WA6RKN <WA6RKN at ARRL.net>
> Message-ID: <351009.14370.qm at web57907.mail.re3.yahoo.com>
> Content-Type: text/plain; charset=iso-8859-1
>
> These make nice light shows at night other than that they do not work worth a hoot.? Maybe at low power like 5 or 10 watts they'd work, but the inefficiency will eat up that small amount of power.
>
> 73,
>
> Bill
>
> AI4WM
>
> --- On Sat, 2/28/09, WA6RKN <WA6RKN at ARRL.net> wrote:
> From: WA6RKN <WA6RKN at ARRL.net>
> Subject: [TowerTalk] Isotron Antennas
> To: "Tower Talk" <towertalk at contesting.com>
> Date: Saturday, February 28, 2009, 11:10 AM
>
> If you gentle readers would bear with me while I take an excursion into some 
> antenna type questions....
>
> Specifically, the Isotron Antenna.
>
> Being a skeptic, this antenna sounds too good to be true..
>
> So..I ask you folk..Opinions?  Thoughts....good or bad.....
>
> (Or any suggestions of a small footprint antenna for use from an apartment 
> landing.  This one caught my attention as one could BS the apartment 
> management and say it was a fancy sat dish.  They wouldn't know the 
> difference.  LOL)
>
> Limited area for an HF antenna and severe restrictions necessitates the 
> search and questions.
>
> Dipoles and other wire antennas are out.  Verticals are pretty much out as 
> well.
>
> Thanks in advance!
>
> Joe Wolfe
> WA6RKN 
>
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> End of TowerTalk Digest, Vol 75, Issue 2
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