Why does the panadapter show the location I'm listening to, 100k off from where the yellow line is located?

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  • Updated 2 months ago
  • (Edited)
This isn't a big deal, more of a curiosity but, why does the panadapter show the station I'm listening too 100k away from the yellow line? I know I can drag that little space closed, I'm just curious why it defaults to the gap?

73,
Rick - K5RHA

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Richard Adkins

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Posted 2 months ago

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Larry - W8LLL

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Because your receive locut passband filter is set to 100. hold your mouse cursor down by the scale and you will see a tool for dragging it.
(Edited)
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Richard Adkins

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How do I change this if not in Radio Setup under Rx?
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George Molnar, KF2T, Elmer

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The highlighted area shows the extent of your audio passband (width).
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Larry - W8LLL

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Wayne

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It is not in radio settings it is the receiver passband filter setting as shown in the pic by Larrry you also have a transmitter filter as well which will determine the width of your. transmitted audio.
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John - AI4FR

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I think it does it because many SSB transmissions cut off the signal there. If nothing is transmitted in that 100hz slot, all you'll add is noise if you open it up. Watch the transmitted SSB signals to decide if you want to open it.
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Ken - NM9P, Elmer

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Correct... The colored band is showing your exact RX filter coverage.
The thin yellow line is your "zero-beat" or SSB "carrier" frequency.

You can see the effect as you change your RX filter bandwidth.

By the way, that is not 100K, but 100 Hz (or 100 cycles per second in us OLD guy's language.) 
100KHz would indeed be a serious discrepancy.

Ken - NM9P
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Jay / NO5J

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Rick

It defaults to eliminating 0 Hz to 100 Hz because those audio frequencies contain the least useful, speech information. But may have an effect on what the AGC is trying to level.   But you can override that default easily. I often clean it up further by eliminating 0 Hz to 200 Hz when working SSB. Then I can raise the volume of the speech portion without over emphasizing the bassier content and whatever band noise that might muddy up what I hear.

Once you figure out what your own filter preferences, save them to a global profile, and the the profile will override those defaults for you automatically, if your reload and then run using that profile. 

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         73, Jay - NO5J

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Ken - NM9P, Elmer

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You will appreciate that even more when you are trying to copy what I call the "Super-Bass" guys when they are weak....  All bass, no articulation frequencies = NO COPY on weak signals!  But if I slide the RX low-cut frequency up to 150-300, depending upon the station then all is good!  (Or at least better)...

The neat thing about the graphic display is that you can zoom in and see their excess Bass peaks and watch as you filter them out.  You can tell when your filter low end custs off the super-bass.

Ken - NM9P
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Robert Lonn

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Ken, this is what makes FLEX so NEAT, lots of flexibility and Visual Feedback on what is going on!! After 3 months with my 6600M, still learning all about its capabilities!! I am glad the FLEX is complicated!! Makes all of this just that more FUN!!!! If I wanted Simplicity, well they make radios that are simple!! LOL

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Geoff AB6BT

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WOW!!! I have a pair of those without the 7-segment display. I think there were 3(?) crystals you could install for your favorite channels. 
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Craig Williams

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I still have one.
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Richard Adkins

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I've just been modifying my settings in the EQ to get the xmit and rcv sounds I like. Looking at the panadapter on xmit to see how it's going out and, of course, asking how I sound once in a while.

It's all slowly coming together. 
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KK9W - Steve

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That gap is NOT 100k it is 100hz as to where one side of your filter is set
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Richard Adkins

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Yip, I figured that soon after typing it. lol  
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Michael Coslo

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While we are here, if you do digital stuff like PSK or FT9, you should use Digu or Digl. That will bypass the equalizer, because for the Digital stuff, you don't want modified sound. Have fun!
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Rick WN2C

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Actually is it 500 Hz. It is approximately half way between 14272 and 14273 making it 500 hz of bottom end of the voice signal. Click on the flag where it says USB and the drop down will open. Select the bandwidth you like and it will fill in. Set you mouse cursor on the bottom of the slice as in Larry's w8lll's pic and it will show you the low cut and the high cut of your receive bandwidth.
(Edited)