Whats the logic for using DIGU instead of USB for FT8. If you use usb with a 4K filter you can see the whol

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Whats the logic for using DIGU instead of USB for FT8. If you use usb with a 4K filter you can see the whole band and jump any where to transmit.
\73 Al, N4AB
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Al

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Posted 11 months ago

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George Molnar, KF2T, Elmer

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DIGU removes any transmit audio processing or shaping, providing a nice clean, flat response for your digital operation. In receive you can also use wider bandwidths - I use 5 kHz on HF.
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Jamie WW3S

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Can use wide bandwidth in digiu as well...
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Neil D Friedman N3DF

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I find the "wide graph" contained within the FT8 program to be much more useful in finding a free transmit frequency than attempting to use the SSDR screen.
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Winston VK7WH

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Another reason is that DIGIU turns off all processing
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Winston VK7WH

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Sorry, I didn’t see the earlier reply.
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Ria - N2RJ, Elmer

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I seem to remember someone (might have been steve) saying it also had lower latency.
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Jay / NO5J

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Al
DIGU / DIGL, and USB / LSB modes on a Flexradio, differ only in the fact that DIGU and DIGL modes bypass any, and all, DSP processing effects. You don't want any EQ-ing, or noise filtering being done on the signals your trying to decode. USB / LSB modes don't bypass those. Think of it as quick, convenient way to ensure that your sending unadulterated signals to the Digital Application your using. The choice is yours though, you can use USB / LSB and disable all the effects manually.

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   73, Jay - NO5J

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Jay / NO5J

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Al

Also, the bandwidth filters are optimized for digital applications when using DIGU, they will either all use a 1500Hz center frequency or will be wide filters that start at 0 Hz and then go up to some useful upper cutoff point, like 3k or wider. Whereas USB filters are optimized for voice operations.

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   73, Jay - NO5J

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Paul Leach

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Brilliant question and good answers.

It was like asking one of those questions that one is afraid to ask

I always wondered what the difference was

Thanks Al

Paul