For FT-8 TX Settings

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  • Question
  • Updated 10 months ago
  • Answered
I have the 6500 and would like to know if there are preferred TX equalizer settings for FT-8? Should it even be turned on?
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W9ILY

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Posted 1 year ago

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Jim Gilliam

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That's a good question. I have wondered if the TX equalizer is bypassed when using the DAX.


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Ken - NM9P, Elmer

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Dax in and of itself -- NO.  But when using DigU/DigL the EQ and Processor are turned off.  but watch the audio input levels.  Digital sigs don't like overdrive...
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Ken - NM9P, Elmer

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Official Response
Always run FT8, and all other digital modes except RTTY in DigU, which turns TX EQ, Compression, etc OFF.  (Run RTTY in RTTY Mode, unless you are using FLDigi)

You DO need to make sure that the Mic Profile you use for DigU has the transmit filter set wide enough (Usually 3K on FT8) that your total audio spectrum will pass as you move within the FT8 passband.

Then you also need to watch the Audio level so that you are at least a few dB below the Red Line to avoid distortion caused by overdrive.

Ken - NM9P
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Bob Gerzoff, WK2Y

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No equalizer. Flat across.  No compression either.  I know you can still highlight the buttons and it seems to me that the equalizer is not by passed using DAX, but I can not confirm.  
73,
Bob, WK2Y
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Tim - W4TME, Customer Experience Manager

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All DSP audio processing is bypassed, including the EQ.
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Bob Gerzoff, WK2Y

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Great to know. Thanks Tim.
Hope your recovery is continuing smoothly.
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W9ILY

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So is it better to run FT-8 in DIGIU or USB with no compression or does it make any difference?
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David Decoons wo2x, Elmer

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DIGI-U

Dave wo2x
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Ken - NM9P, Elmer

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Always use DigU. Then you can have a Mic Profile for the digi modes that doesn’t conflict with your SSB Mic Profile. And you won’t accidentally leave EQ set or PROC on.

Why do anything else?
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Tim - W4TME, Customer Experience Manager

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Always use DIGx for digital modes.  For FT-8, use DIGU
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W9ILY

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Thanks for all the responses. It sure clears up things.
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Dave - WB5NHL

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Also watch your TX power setting.  FT-8 is a 50% duty cycle. The FLEX PA temperature can build up pretty quickly.  Use K9DUR SDRMonitor utility or FRStack to watch the temps.
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rjguidrysr

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TX filter got me last night. OPEN up Wide if going over 3khz