What Causes This?

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  • Updated 5 years ago
I  have included a screenshot of one of the bands here. This is seen on a couple of bands. What is causing the hump in the baseline?


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W5UN_Dave

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Posted 5 years ago

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Tim - W4TME, Customer Experience Manager

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Is your antenna connected or disconnected?  If connected and you disconnect it and the noise decreases, then it is real external noise.  A little broad banded, but not too strong (-105 dBm).
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Tim - W4TME, Customer Experience Manager

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What happens when you zoom the panadapter out so that the WIDE indicator is shown at the top?
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W5UN_Dave

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Tim this is what it looks like with everything disconnected except LAN. This all goes away below  16 mHz.
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Tim - W4TME, Customer Experience Manager

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What is your RF preamp setting?
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W5UN_Dave

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Tim this is what it looks like with everything disconnected except LAN. This all goes away below  16 mHz.
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W5UN_Dave

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Tim, the waveform stays the same at any preamp setting, but it disappears at a -10 gain setting. Maybe a bit lower at gain of 0.