[TowerTalk] Fw: Temporary tower/antenna question

[Gene Fuller]

----- Original Message ----- 
From: "Gene Fuller" <w2lu at rochester.rr.com>
To: <K7LXC at aol.com>
Sent: Sunday, February 03, 2013 5:01 PM
Subject: Re: [TowerTalk] Temporary tower/antenna question


> Hi Steve -
>
> My favorite for portable operation for some time has been a forty foot 
> center fed wire vertical dipole fed with 450 ohm window line. I use a 
> little home brew balanced tuner (floating ground "T" network with 4:1 
> balun at the low Z end). This provides reasonable low angle takeoff 
> (especially if near salt water) is fairly efficient, and is easy to pack. 
> I have also used it with fair success on 80 by clipping a 100 foot 
> extension to the top. When combined with one of the little transceivers 
> and switching power supplies it is easily carried in a small carryon 
> suitcase if you're flying.  I sometimes take along one of the collapsible 
> fiberglass masts and tape the antenna to the mast. The length certainly 
> isn't critical but if you get much more than 40 feet the main lobe starts 
> braking  up on 10 meters. If ten is of no consequence  the length can be 
> increased to about 60 feet  to better accommodate 15-40 meters. 
> Considerations include type of operation contemplated  i.e desired takeoff 
> angle, type of location (salt waster, mountain top, etc), bands of 
> interest. Rule of thumb re length :  if you want to stay away from lobe 
> splitting keep it less than 5/8 th's wave on highest frequency. For 
> useable efficiency keep it at least 40% of a half wave on the lowest 
> frequency (clipping extra wire on even just end for night time use is one 
> "workaround").
> I've had a pretty good time with this approach - it's easy to implement, 
> travels well, works well, and is fairly inexpensive. Although a balanced 
> tuner with the balun at the radio side is a bit more efficient, the 
> commercial tuners that use a balun at the antenna side of the tuner would 
> probably work fairly well also.
>
> Gene / W2LU
>
>
> ----- Original Message ----- 
> From: <K7LXC at aol.com>
> To: <towertalk at contesting.com>
> Sent: Friday, February 01, 2013 4:36 PM
> Subject: [TowerTalk] Temporary tower/antenna question
>
>
>> Howdy, TowerTalkians --
>>
>>    I'm researching temporary antenna installations  (like Field Day) and
>> was wondering if you have some input. What did you  use? How did you 
>> erect
>> it? Materials? Hints and kinks?
>>
>>    This is with an eye towards safety and  effectiveness. I don't need
>> real specifics (like what antenna to use) but  general thoughts and
>> considerations. Tnx for any input.
>>
>> Cheers,
>> Steve    K7LXC
>> _______________________________________________
>>
>>
>>
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>