As he stated though, the loss is often minimal.
Best regards - Brian Carling
AF4K Crystals Co.
117 Sterling Pine St.
Sanford, FL 32773
Tel: +USA 321-262-5471
> On Apr 27, 2015, at 12:42 PM, Al Kozakiewicz <akozak@hourglass.com> wrote:
>
> SWR is determined by the feed point impedance of the antenna and the
> characteristic impedance of the transmission line. The tuner can't do
> anything about SWR on that line, only match (hopefully) the radio's nominal
> 50 ohm impedance to whatever the conjugate impedance is at the radio end of
> the transmission line.
>
> Al
> AB2ZY
> ________________________________________
> From: TowerTalk <towertalk-bounces@contesting.com> on behalf of Tom Osborne
> <w7why@frontier.com>
> Sent: Monday, April 27, 2015 12:36 PM
> To: towertalk@contesting.com
> Subject: Re: [TowerTalk] G5RV vs 40M dipole
>
> One thing I have noticed with the built-in tuner on my radio is that all
> it does is make the radio happy.
>
> The radio shows a 1:1 SWR, but the meter past the radio still shows a
> high SWR, so if there is loss on the line, even though the radio is
> happy, the loss is still there. I think the tuners just give us a false
> sense of security. 73
> Tom W7WHY
>
>> On 4/26/2015 9:23 PM, Fuqua, Bill L wrote:
>> Not everyone knows that a tuner only protects the rig. That is the job of
>> a dummy load.
>> In fact the tuner matches the impedance of the antenna system to the rig and
>> not only that,
>> by doing so providing the antenna with a conjugate match, that is to say the
>> antenna's radiation
>> resistance is matched and its reactance is also matched by the equal and
>> opposite reactance thus
>> making the antenna system resonant. If the antenna has a radiation
>> resistance of 10 Ohms and
>> a capacitive reactance of 100 Ohms the antenna tuner matches it with 10 Ohms
>> real resistance and
>> an inductive reactance of 100 Ohms thus providing maximum energy transfer.
>> While at
>> the same time it provides 50 Ohms resistive load for the transmitter.
>> Resonating the antenna system with a tuner is equivalent resonating the
>> antenna. The only difference
>> is that there may be some additional losses within the tuner and
>> transmission line which are generally
>> minimal at HF frequencies. Also, there is a reduction in bandwidth of the
>> antenna system.
>> Yes it does change the currents and voltages in the antenna. The G5RV was
>> an antenna developed back
>> when we had tube transmitters with a PI network output that could
>> accommodate a broad range of
>> impedances. It also was made to work on 5 bands.
>> Just about every AM broadcast antenna system has an antenna matching
>> network. It is a shame that
>> they don't work.
>> 73
>> Bill wa4lav
>
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