[Elecraft] Random wires

[Sandyb]

The 1/2 wave antenna has been some what of an enigma to a lot of people over 
the years. I used one for years and still use one today.  I work mostly the 
"Low bands" (160-30) and never wanted the bother of keeping up an HF beam up 
a tower!  I DID go thru an extreme VHF/UHF stage when I was on 144/432 Mhz. 
and contemplating some 1296 operation though.  The activity down here fell 
way off and I finally sold all the goodies as they became useless when the 
trend towards VHF/UHF fell apart when nearly all the old timers went SK.  No 
use being able to run 500 watts PEP on 2 SSB when there ain't anybody to 
talk to more often!

The end fed Zepp or just a "plain" end fed 1/2 wave can be big trouble when 
you run a lot of power as there is inevitably the "RF in the shack" syndrome 
forcing changing antenna lengths to compensate for the problem.  I am 
presently using a 115 end fed which is ideal for 80-30 including the 60 
meter band.  You can get by with a poor ground system and still radiate a 
pretty decent signal with just something like a very simple "L" section 
network to match it to your rig.  Ground losses are much less with little or 
no effect from adding counterpoise wires/grounds to suppress mostly "RF in 
the shack" troubles, which are minimal on QRP and 100 watts or less.


Lots of people look upon the half wave with distain, but it can do a 
remarkable job, especially in neighborhoods where beams and "visible" 
antennas are frowned upon by Home Owners Associations and the attendant 
"trolls" looking for "errant amateurs" to torment.  The 115 wire I now have 
up was used out of a hasty attempt (successful!) to get back on the air when 
my XYL had a stroke which didn't mix well with my outdoor "ham shack" in the 
carport building!  I regularly work CW with it with 100 watts or less from 
80-20 meters and also SSB in the afternoons on 40 and nights on 75 meters 
with the "big boys". I'm using #26 stranded "mil spec" hookup wire for the 
radiator and it works VERY well for what it is and the House wiring ground 
buss for a "counterpoise"!

Don't sell the antenna short, it can and will work very well if the right 
length and with a decent antenna tuner.

73 to all,

Sandy W5TVW

-----Original Message----- 
From: Fred Jensen
Sent: Tuesday, October 01, 2013 5:42 PM
To: elecraft at mailman.qth.net
Subject: Re: [Elecraft] Random wires

Isn't this why AM broadcast stations, particularly 50KW clear-channel
stations, employ base-fed half-wave verticals?  They still use radial
fields too I think.  I recall [from years ago] that KFI's TX [650KHz]
was in Buena Park CA and the tower was around 700ft tall.  BW of a stick
like that is pretty narrow, uncompensated, less than the BW of the signal.

When I saw the original post, I knew it would stimulate a reply-storm. :-)

73,

Fred K6DGW
- Northern California Contest Club
- CU in the 2013 Cal QSO Party 5-6 Oct 2013
- www.cqp.org

On 10/1/2013 2:43 PM, Ron D'Eau Claire wrote:
> I disagree. Barry has it right. The radiation resistance of the radiator 
> is
> independent up the ground resistance. That's why a 1/2 end fed wire with
> it's very high resistance is highly efficient against a given ground 
> system
> compared to a 1/4 wave long or less wire.


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