Background noise level control

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  • Updated 2 years ago
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I overheard some ops talking about using an IC-7300 and while tuning across a band they heard nothing but signals because between signals the noise was muted.  I thought surely my 6300 must have some similar capability.  I use FRStack and am familiar with its Squelch but find it kind of finicky.  

A search in this Community found many queries about when SmartSDR will provide an All Mode Squelch, but there was also some mention about using slice AGC.  

I normally run AGC at Medium with the slider about 50.  I tried reducing the slider to about 25 and noted the noise was significantly less between signals.  Is this the same capability the IC-7300 is likely using?  I have not played with a 7300 so don't know how it compares.

Is there a better way to kill background noise between signals using SmartSDR in SSB modes?  
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Dick B

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Posted 2 years ago

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k3Tim

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If you set the AGC correctly the background noise will be dropped significantly and signals will make it thru. I was listening to some 75m SSB stations this morning and had set the AGC (~35) and also set NR to 1 or 2 and enabled. Also one can cut the hi-freq audio in the equalizer and end up with near squelch quieting. 

There is also the most excellent program "Stacks for Flex" that has a software squelch.

There is a good explanation about the AGC Threshold on the older Flex series which I suspect applies to the 6k series but some Elmer in the know would have to confirm this. 

Best Regards,
Tim
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Dick B

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Yes, I just read the AGC-T section of the current SmartSDR manual and found my knee at about 26 on 20M and 17M.  It's certainly not as quieting as a squelch but does make a useful difference.

As I mentioned, I do use FRStack and find its Squelch a bit finicky.  

Would love to see the All Mode Squelch in SmartSDR!
  
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Tim - W4TME, Customer Experience Manager

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Using a squelch (noise gate) only improves the apparent signal to noise ratio (SNR) because when listening to the signal, the noise is still mixed with the signal.  You really want to use the AGC-T as described above because that improves the actual SNR for the signal of interest.
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Dick B

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Yes, I understand that but the squelch is not for SNR it's for sanity and user enjoyment!  
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Bill NE1B

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I also agree for sanity and domestic tranquility!  I like the Kenwood TS-2000 squelch for that reason.  I monitor VHF calling frequencies on SSB for band openings while reading or working in my office.  A quiet environment is much appreciated...until the action begins!