Dragging panadapter changes Tune and AGC Threshold settings

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Why does dragging the panadapter change my Tune and AGC Threshold sliders?  The Slice frequency does NOT change and stays right in the ham band that is still totally visible.  These two sliders are the only thing I notice that changes.  It caught my attention because the change in AGC Threshold causes my noise level to increase noticeably.  

I noticed this when I zoomed out to monitor 14000-21000 with the slice on 17M then dragged the panadapter a bit.  
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Dick B

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Posted 2 years ago

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Rick Hadley - W0FG

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I just tried that and can see what you mean.  My guess is that somewhere in the process, it drags across one of your preset profiles and switches to the settings there, because in my case at least, it also turns on the NB, NR, and APF.
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Ken - NM9P

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I think that is close to what is happening. But I don't think it is preset profiles as much as it is band persistence that is involved. 

When zoomed out to a wide pan and sliding back and forth, the center frequency of the panadapter is crossing the lines between different ham bands or the GEN band, and the information that is saved in the band persistence.

When it crosses into another band's "control zone" (for lack of a better term)  the band persistence for that band takes over and changes several settings, including some of your DSP, AGC, Display parameters, axes scales, etc.

At least this is how I have tried to explain it to myself when I experienced this behavior.

Ken - NM9P
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Tim - W4TME, Customer Experience Manager

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Ken is right.  When you expand out the panadapter, the frequency range is no longer in a ham "band"  (frequency segment)  and is in the GEN band, then persistence kicks in and changes those parameters.
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Rick Hadley - W0FG

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Does the GEN band maintain its own persistence? I.e., does it hold the same settings anywhere outside of the ham bands?
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Tim - W4TME, Customer Experience Manager

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Yes, the GEN band, the default "band" if you are outside of the generally accepted HF/6 ham bands (frequency ranges) or the ones you define via the XVTR form.
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Dick B

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I hear you Tim but that is totally illogical as my slice is still set Active and TX in the HAM band and I can still transmit except that many of my normal settings for that band have now been changed.  I would much rather sacrifice receive performance as opposed to transmit when the slice is still Active and TX, despite the bandwidth on the panadapter.  Is that not reasonable?  
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Tim - W4TME, Customer Experience Manager

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That is a function of the radio architecture.  In the same way a 6500/6700 switch the preslectors out when the panadapter is wider than the band. 

Also, transmit performance is not affected by a wider panadapter.
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Stan - VA7NF

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Also, there are many frequency range boundaries (bands)  that change the settings as the slice crosses them.  Allows different receive characteristics per "band"; convenient but disconcerting.  Been that way since pre V1 beta