If you listen to AM in SAM mode you will be effectively listening in DSB mode. Gerald
Gerald Youngblood, K5SDR President FlexRadio Systems 13091 Pond Springs Rd. #250 Austin, TX 78729 Phone: 512-535-4713 -----Original Message----- From: Jim Lux [mailto:[EMAIL PROTECTED] Sent: Thursday, July 10, 2008 9:15 AM To: [EMAIL PROTECTED] Cc: [EMAIL PROTECTED]; 'Maarten'; 'FlexRadio Reflector' Subject: Re: [Flexradio] TX Audio Quality Help, please! Quoting Gerald Youngblood <[EMAIL PROTECTED]>, on Thu 10 Jul 2008 06:50:23 AM PDT: > Mike, > > In all FlexRadio models, AM is really an amplitude modulated 11 KHz > carrier that is transmitted in SSB mode on exactly the same hardware > signal chain as the SSB signals. In other words, AM is a SSB signal > on both the 1000 and 5000. AM and SSB are both transmitted the same > way from the digital to analog converter through the PA stages to the > antenna. There is no hardware difference. > > Gerald > > > Maarten, the abnormality is always there in all bandwidths in the ssb mode. > The audio in the AM mode can best be described as superb. I think most > of us have a desire to have the Flex line of radios to be the best > that are out there in all parameters. Well, the ssb audio has a problem. > There are many inside and outside the Flex company that have been and > are in various forms of denial. You may be comfortable with that. > However, as you can see from this reflector, there are many that hear > the problem and would like to see a cure. > > Mike, K6ZSR > Same transmit chain, BUT, very different detection method between SSB and AM. I'm sure there are Tx anomalies that could occur that would be readily detectable with SSB but not with an envelope detector. An interesting case is where the two sidebands are fading independently. Another case is where there are instantaneous changes in the carrier frequency. With SSB receiver, you'd hear it, with AM detection, you wouldn't. Not that either of these represents what's actually going on. The interesting question is whether, when listening to an AM signal, using a SSB receiver, what it sounds like. (and assuming the SSB receiver has good enough selectivity to suppress the carrier and opposite sideband) _______________________________________________ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kb.flex-radio.com/ Homepage: http://www.flex-radio.com/
