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Removing ASCII graphs from Doty post
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Larry Gadallah committed Sep 16, 2023
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113 changes: 2 additions & 111 deletions _posts/2005-09-15-antenna-guru.md
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![50 ohm mismatch]({{ site.url }}{{ site.baseurl }}/assets/images/doty1.gif)

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> The second graph assumes a matching transformer with a 9:1 impedance
> ratio at the feedpoint, presenting the antenna with a load resistance
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![450 ohm mismatch]({{ site.url }}{{ site.baseurl }}/assets/images/doty2.gif)

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> Well, so what? In the absence of interference, the signal to noise
> ratio is the main determining factor for the audio quality of the
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![50 ohm SNR losses]({{ site.url }}{{ site.baseurl }}/assets/images/doty3.gif)

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> Losses in signal to noise of 3-5 dB are likely to be noticeable.
> The largest impact is in the quiet bands above 15 MHz.
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> On the other hand: the loss in signal to noise with a 450 ohm feed
> is much smaller:
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![450 ohm SNR losses]({{ site.url }}{{ site.baseurl }}/assets/images/doty4.gif)
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> You are unlikely to be able to notice losses in signal to noise in
> this range.
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