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Re: Topband: question about antenna bandwidth

To: "Rob Stampfli" <rob@cboh.org>, topband@contesting.com
Subject: Re: Topband: question about antenna bandwidth
From: k8gg@voyager.net
Date: Tue, 8 May 2012 08:03:40 -0400 (EDT)
List-post: <topband@contesting.com">mailto:topband@contesting.com>

Rob:

A typical 3/8 wl inverted-L antenna is about 65 feet
vertical and 125 feet horizontal or sloping back downwards at a slight
angle.  This means that 2/3 of the wire is horizontal near the ground
and is a high angle radiator - semi NVIS - and the vertical part is
radiating at a low angle.   Not good unless you want to work a
lot of US and nearby VE stations.

It would be best if you can
model the various configurations of 1/4 wl, 5/16 wl and 3/8 wl inverted-L
antennas on a PC so you can see the results on the monitor and print them
out for evaluation.

IMHO going beyond 160 feet of wire
inverted-L (5/16 wl on 160 meters) is not the best solution.
Just my
2 cents worth

73 & GL     
George  K8GG


> Thanks, gentlemen (Eddy, K8GG, ZR,
Roy, Herb, et. al.), for all the 
> feedback on this. So, it seems
it's pretty much what I expected -- 
> if you tune an antenna for
better results on one frequency, you 
> detract from its operation
on another. Maybe one of these days I'll 
> get around to playing
around with that 3/8 wavelength L anyway... 
> 
> Rob /
KD8WK 
> 
> On Mon, May 07, 2012 at 03:22:19PM -0400, Herb
Schoenbohm wrote: 
>> Another rule for this is "the lower
the Q of the matching network the 
>> greater the
bandwidth." 
>> 
>> Herb Schoenbohm, KV4FZ 
>> 
>> On 5/7/2012 1:48 PM, Roy wrote: 
>>
> If I were to extend my 1/4-wave inverted-L to a 3/8-wave L, and tune

>> > out the inductance with a fixed capacitor at the base,
what would this 
>> > do to the broadbandedness of the
antenna? 
>> > 
>> > There is an old basic
principle to remember about this, "The fewer the 
>> >
components in general, the broader the bandwidth." 
>>
> 
>> > 73, Roy K6XK 
> 
>
_______________________________________________ 
> UR RST IS ...
... ..9 QSB QSB - hw? BK 
> 

_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK

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