Using you analogy, substitute a 50-ohm dummy load and call it an "antenna".
Very little power will be lost in the "cable" and all the power will be
radiated by the "antenna". The dummy load isn't resonant but your xmitter
will be very happy to pump power to the "antenna" since it sees the proper
impedance. The big "oops" is that the radiation efficiency of the dummy
load antenna is very poor and most of the power goes into heat. A matched
resonant antenna can be very close to a dummy load if its radiation
efficiency is poor.
In summary, its radiation efficiency and not resonance that makes the
difference as long as you match the load in both cases.
73 de Perry - K4PWO
----- Original Message -----
From: "bill rubin" <brubin2010@gmail.com>
To: "Dave - AB7E" <xdavid@cis-broadband.com>
Cc: "Towertalk e-Goups" <towertalk@contesting.com>; <k6xyz@sbcglobal.net>
Sent: Friday, August 07, 2009 01:50 AM
Subject: Re: [TowerTalk] Resonance is over rated
> True... but the comment is that was resonance was overrated. I disagree.
> Sure an transmitter can be "happy" with seeing proper impedance (like with
> antenna tunner) but how much power is getting to that antenna ? How much
> is
> lost is the cable ? thats my point.
>
>
> On Fri, Aug 7, 2009 at 1:20 AM, Dave - AB7E
> <xdavid@cis-broadband.com>wrote:
>
>>
>> That's a fairly ambiguous statement from K4IPV and I think you are
>> possibly
>> misinterpreting it. I can put a properly designed L-network at the base
>> of
>> a 50 foot high 80m vertical and it will do exactly what K4IPV recommends.
>> It has nothing to do with whether the antenna is inherently resonant or
>> not.
>>
>> 73,
>> Dave AB7E
>>
>>
>>
>> ------Original Mail------
>> From: "bill rubin" <brubin2010@gmail.com>
>> To: "Dave Harmon" <k6xyz@sbcglobal.net>,
>> <towertalk@contesting.com>
>> Sent: Thu, 6 Aug 2009 23:44:16 -0500
>> Subject: Re: [TowerTalk] Resonance is over rated
>>
>> per the book Antenna Toolkit by Joseph J. Carr, K4IPV
>>
>> "The only really proper way to reduce the VSWR to 1:1 is to tune the
>> antenna to resonance and then match the impedance."
>>
>>
> _______________________________________________
>
>
>
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