That's it precisely. Should be able to resolve the exact frequency and phase of the carrier. There's a lot of information there to work with (take a look at that waterfall with SSB you'll see what I mean). Given the carrier is rock stable with time it should be possible to do this with VERY good accuracy. I don't think it'd be all that hard at all.
Not a lot of point doing this on your own unless you've got an open source rig. I don't. I've got Icom and Elecraft. Reckon it could be done and tested in the PC via a soundcard. I'd be more than interested in doing it if Elecraft were at all interested (even in an evaluation). It'd feel like a contribution to the amateur pool, I'd love to bring a little of my work into the hobby. There's probably plenty of DSP guys like me on this list that could do it. I tune for the "natural" sound that prompted Erik to write his original post. It feels a bit like getting all the lows to "line up" but when you do find the spot it's sweet. If you're in a particularly anal mood it can be a challenge. It's this that has made me contemplate the possibility many times. 73's Peter VK4JD -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Wright, Robert Sent: Tuesday, 5 February 2013 3:54 PM To: [email protected] Subject: Re: [Elecraft] [K3} [KX3] SSBT like CWT ? This sounds like an interesting project. It would seem that the technique would be finding the offset frequency that provides the best alignment of harmonics, which is what we naturally do by ear. Not difficult, but would probably need a bit of tweaking to provide good real-time performance. It would only be valuable if it was significantly faster than what we do manually. It's good when projects are self-motivating. 73, Bob, N7ZO -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Peter Lambert Sent: Monday, February 04, 2013 9:25 PM To: 'Erik Basilier'; [email protected] Subject: Re: [Elecraft] [K3} [KX3] SSBT like CWT ? You are spot on, Eric This is an algorithm I've contemplated writing many times. Voice results from the vocal cords snapping together in the range around 85Hz. The filter effect of the various cavities, throat, mouth and nasal are quite high Q and filter the harmonic rich vocal chord excitation to produce the voice. If you watch an SSB signal on your PSK waterfall you'll clearly see the harmonics of the vocal chords. I think a DSP algorithm that calculates the location of the carrier based on the separation between the vocal chords is a definite doable proposition. It would give SSB the perfect clarity you seek. Love to have a go at this (I do DSP). Do you Elecraft guys want to have a go or interested in using it if I do it ? (I could probably do it as a piece of PC code that processes sound card input so you could evaluate it). Doesn't feel like to be a difficult thing to do. Cheers, Peter VK4JD -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Erik Basilier Sent: Tuesday, 5 February 2013 3:07 PM To: [email protected] Subject: [Elecraft] [K3} [KX3] SSBT like CWT ? At Field Day I have observed a number of operators operating SSB. I have noticed that there is a great variation in skill when it comes to tuning the RX to an SSB signal. Sometimes I feel that the op has it tuned all wrong and I almost want to grab the knob. Maybe different people's brains focus on different aspects of the sound when they tune the RX. Some people seem to want to tune for the best balance between highs and lows, when the HI CUT and LO CUT would do a better job. When I tune the RX, I believe that I am not trying to balance highs and lows, but rather trying to find some kind of harmony in the sound. If I were tuning in a piece of music from an AM BC station with the radio in SSB mode, clearly the harmonics of a musical note will not be harmonious if the radio tuning is off. If a voice is used for singing, it is like a musical instrument. If the voice is speaking, I believe the harmonics are still at play as with a musical note. This leads me to speculate that it would be possible to run an FFT on the received audio and determine by how much the RX tuning is off, just like with CWT. I am very fond of the CWT feature on the K3 and on the KX3. I wonder if it would be practical to add SSBT as a new feature. 73, Erik K7TV ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
