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Re: CW Filters


 

Hello Bill

Thanks for the feedback. I would love to hear from Braden too. When not liking the way something works, one should be able to propose an improved alternative.?
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From the user perspective, I've found most other radios have you set your preferred CW tone/offset (500hz, 600hz, 700hz, etc.), then choose a bandwidth around that tone.? The QMX+ however presents you with a list of bandwidths that can be used with several CW tones, then you must either live with the bandwidths that are available for your chosen offset, or choose an offset based on the bandwidths you'd like to use.?

Is it possible to?change?the CW filter set up so that you can simply choose your offset, then choose the bandwidth?? Or, stated differently,?can the CW filters be made so that every bandwidth applies to every offset/tone?

Yes this is exactly the?desired end goal. The reason it is the way it is now, is because way back there was just the 300 Hz filter. In the original way I had the code set up, there was just this single filter. It was suggested that two offset overlapping versions of the same filter could be used and that would provide a narrower bandwidth without causing ringing and increases in delay.?

As it happened I already had on hand from way way back, 10 years ago, I can't even remember where from, sets of filter coefficients for a bunch of other filter centers and widths. It was a small amount of effort to code this, and I released it in firmware 1_00_024 on 6-Aug-2024. At that time I had already begun my main 9 month project of implementing SSB in QMX, which so so many people have been waiting for, and I did not want to spend a large amount of time redesigning audio code. I wanted to stick to minor changes where possible. This implementation of the two overlapping filters was a low effort thing but provided great benefit to CW operators. But it isn't ideal, I know. It was intended as a temporary measure, with better ways to be implemented post SSB.?

73 Hans G0UPL

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