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A comment on Serial Port SDR. Parent comment

Re:Serial Port SDR by bluGill on Thursday December 06, 2018 @09:30AM (#18618286)
He didn't say this, but I suspect that his antenna was that specific length for rf reasons - wires work best as antennas when their length is some multiple of the wavelength. (ask an rf engineer if you want details, I'm close enough for discussion but all rf engineers will cry when they read that)
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Re:Serial Port SDR by wglb on Thursday December 06, 2018 @10:27AM (#18618742)
Multiples of 1/4 wavelengths, and if built properly 5/8 wave.
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Re:Serial Port SDR by naikrovek on Thursday December 06, 2018 @04:04PM (#18622219)
... but 5/8 isn't a multiple of 1/4, Or is that not what you meant?
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Re:Serial Port SDR by wglb on Thursday December 06, 2018 @04:09PM (#18622263)
Right. I should have added more detail. Multiples of 1/8 also work.

Now, you can actually make almost any length work with proper tuning circuitry, but the ones mentioned are the most effective.

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Re:Serial Port SDR by lima on Thursday December 06, 2018 @12:07PM (#18619817)
Also, there's a big difference between random noise and a modulated signal on a specific frequency, with a matching antenna.

One of those is noise, the other one is a transmission.

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