[Antennas] Fwd: [Johnson] I'm not an antenna expert

[Ed Tanton]

You guys might want to lend John a hand (privately-since he's not a 
subscriber.)

>Date: Wed, 11 Jan 2006 11:43:30 -0500 (EST)
>From: John Lawson <jpl15 at panix.com>
>
>///snip headers
>
>(I'm not an antenna expert) I don't even play one on TeeVee...
>
>   So, in advance of a lot of EZNec work (and I don't have the 
> experience with that program to derive much 'good' out of it right 
> now) - I'd like to ask what may seem to be a rather obvious HF 
> antenna question.
>
>   Due to the usual reasons - my HF antenna is a loop suspended from 
> my backyard fence - approx 430' total, closed loop, 5' off the 
> ground, fed by 450 ohm ladder line back into the shack, using an 
> Ameritron ATR-15 tuner to match the system to my Valiant.  The 
> tuner and transmitter are bonded to a very heavy ground system via 
> an 8' stake less than 3' from the gear. There is no ground system 
> under the antenna, other than that which Nature provided - and with 
> the current winter conditions, the ground is rather wet and conductive.
>
>   This antenna system exhibits the following SWR:
>
>160M - 1.3:1
>  80M - 1.1:1
>  40M -  +3:1
>  20M -   2:1
>  15M -  +3:1
>  10M -  +3:1
>
>  The tuner capacitors end up being  all-the-way-meshed on the 
> 'misbehaving' bands - not so on 160, 80, and 20.
>
>
>   So I'll see Y'all on 3880 and just fergit the rest.   ;}
>
>
>   No but seriously folks: obviously the feedpoint resistance is 
> outside the tuner's ability to cope with it at various frequencies.
>
>   I'm thinking the first unscientific experiment might be to go to 
> the opposite side of the loop from the feedpoint and cut it into a 
> big horizontal bent dipole - mainly because that will take about 45 
> seconds to accomplish - one of the benefits of having one's entire 
> antenna at ahoulder-height.
>
>   But I'd like to get some other opinions - I know there's an 
> electrical Pattern here from the info - and I have some other ideas 
> based on that.
>
>   And no, I can't put up a "real antenna" so I'm pretty much 
> comiited to making this one work as well as I can. Until I move the 
> QTH to somewhere with a few acres and room for Lots of Wire.
>
>
>   Cheers
>
>John  KB6SCO
>
>
>Johnson mailing list
>Home: http://mailman.qth.net/mailman/listinfo/johnson
>Help: http://mailman.qth.net/mmfaq.html
>Post: mailto:Johnson at mailman.qth.net

72/73 Ed Tanton N4XY <n4xy at earthlink.net>
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