Noise floor jumps when I open 4th Panadapter

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  • Updated 3 years ago
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I'm running a 6700 with the latest software.

While troubleshooting this problem, my latest config was to do a factory reset and this time I did not import my old profiles.

I open my first panadapter and select 40M which automatically creates a slice at 7.175 LSB.  I make a note of the noise floor which is around -115 tonight.

Next I start opening more panadapters while watching the noise floor as I open each one.   Each panadapter opens with a slice on 40m - 7.175.  When I get to the 4th panadapter, the noise floor on all of the panadapters jumps to -90.  It also appears that the signals are a bit weaker at this point.

If I delete the 4th panadapter, the noise floor goes back down to -115.  Signals appear to improve slightly.

If I do this with all panadapters on 20m, the noise floor seems to stay the same regardless of the number of panadapters I have open.

Is anyone else experiencing this?   Maybe its just a scaling problem, I'm not sure.
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Norm - W7CK

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Posted 3 years ago

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Ken - NM9P, Elmer

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Did the last panadapter change preamp settings?
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Norm - W7CK

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No preamp settings were changed.  I've done a factory reset twice now.  It may be working normally now. Time will tell..... 

I've also noticed when on 6m, if I slide the panadapter down slightly below the 6m band all of my other panadapters go crazy and the noise floor seems to go up.  I've had to do a factory reset to correct this problem several times now.
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Walt - KZ1F

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Sort of surprisingly Norm, Tim is usually pretty good about checking up on things here over the weekend so he may grab this latest this evening. Since tomorrow is Monday I suspect he'll respond by early morning.

I just tried it on mine, a 6500 on a 22" monitor. Initial noise floor was -125. Upon starting a second, it appeared to drop to -120, same with pans 3 and 4. However, what was really happening is the geometry changed causing a shrinkage in the dbm scale on the right. So while it looked like the noise floor moved it was really the scaling that reduced as next to -120 was -160, so -125 was just a smidge below -120, not half way to -130. Is that actually what you are seeing? Your results will, of course, vary, based on monitor size.
(Edited)
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Norm - W7CK

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It hasn't happened again Walt.  It was definitely a sharp rise in the noise floor.  I performed a new reset (holding OK button while powering on) the 6700.  Instead of importing profiles, I started over.  I have really been wanting to do that anyway so I could clean things up and get the profiles in some sort of sort order that works well for me.  I also now have all of my global profiles using only 4 different Transmit profiles. 

Since redoing all of the profiles and the system reset, I've been playing around with the 6700 all day with several panadapters and slices open.  It has not happened again.
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Walt - KZ1F

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and that is called goodness!
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Tim - W4TME, Customer Experience Manager

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Doing a factory reset can clear out the band level persistence database which can have settings that will change the noise floor like the antenna selection and the panadapter zoom level.  If everything is working OK now, then I'd chalk it up to that.
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Norm - W7CK

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Thanks Tim.  So far, this issue has not returned.