Voice inversion, to put it real simple, is where the actual waveform of the audio is reversed within the sideband. In other words; on say LSB, normally the low freq audio would be on the very right down to DC, and the high end would be on the left end of the passband. Inverting this would create the opposite and would not be intelligible in normal LSB. By dragging the LSB passband to the opposite side of center, where USB would normally be and then re-tuning the signal, you are then able to hear intelligent audio.
If any of you care to try this, try listening this evening around 3700 to about 3750 or so. You will hear odd sounding signals that you can not tune on LSB or USB no matter what you do. However, if you try the method I mentioned above, you will see what I'm getting at. Oh, you can do this with either LSB or USB, just reverse the process for USB and re-tune. Eric, by moving the passband in LSB to USB (or vise verse) will not simply put the rx in normal USB mode, as the audio spectrum is inverted once you pass the center line. On 12/19/06, Eric Wachsmann <[EMAIL PROTECTED]> wrote: > Maybe I'm ignorant here, but shifting the filter to the other side of the > red line would basically switch from Upper Side Band (USB) to Lower Side > Band (LSB) detection. You can certainly transmit in LSB or USB by selecting > the appropriate mode. Forgive me if I've missed the boat entirely here. > > > Eric Wachsmann > FlexRadio Systems > > > -----Original Message----- > > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] > > radio.biz] On Behalf Of A.R.S. - W5AMI > > Sent: Tuesday, December 19, 2006 9:06 AM > > To: Flex Radio > > Subject: [Flexradio] SSB Voice inversion > > > > With the recent band expansions, I've noticed a lot of SSB ops using > > voice inversion in the new areas of the phone subband on 80 meters, > > most around 3.725. I found it easy to decode the inversion on the > > Flex by moving the entire passband to the opposite side of the > > selected sideband on the console. Unfortunately, it doesn't appear > > that one is able to transmit voice inversion by adjusting the tx > > bandpass to the opposite side. I don't know if this is simply limited > > by the spinner controls for the limits, or if there is some other > > reason the Flex could not do this. > > > > I really don't know what purpose voice inversion would serve, other > > than somewhat masking the conversation from others, however it does > > appear to be legal: > > > > A response from the FCC: > > > > "The question you ask has been asked before. Section 97.113 prohibits > > amateur > > stations from transmitting messages in codes and ciphers intended to > > obscure > > the meaning of the message. If the code or cipher is publicly available, > > then transmitting messages in the code or cipher would not appear to be > > for > > the intent of obscuring the meaning of the message. > > > > William Cross > > FCC" > > > > Anyone know of a way PowerSDR can transmit SSB voice inversion? > > > > 73 > > Brian / w5ami > > > > -- > > "There is nothing more uncommon than common sense." -- Frank Lloyd Wright > > > > _______________________________________________ > > FlexRadio mailing list > > FlexRadio@flex-radio.biz > > http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz > > Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ > > FlexRadio Homepage: http://www.flex-radio.com > > -- "There is nothing more uncommon than common sense." -- Frank Lloyd Wright _______________________________________________ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com
