On Jul 8, 2008, at 12:18 PM, K6JEK wrote: > It not just Jeff. I'm one of the guys who've been listening to the > various audio tests. We first noticed something funny in someone > else's 5000 before Jeff even got his. We ran experiment after > experiment. This guy finally returned his for a refund. Then another > fellow (not in the local rag chew group) broke in with his 5000 to > say he's just waiting for someone to figure this out. His 5000 had > the same problem. We've been listening and recording with a variety > of equipment ranging from 1000's to direct conversion home brews. > > It is subtle. It might be rare. But it is not unique to JCA > > I think Jeff's nailed it. The audio up through the driver stage is > perfect. It gets funky in the final. Why and what to do about it is > another matter.
Has anyone run single-tone and two-tone tests and looked at the distortion products? (THD and IMD). If you can hear it you can probably measure it. The spectrum will tell you something about what might be causing it. Oh, has anyone looked at the gain of the PA? If the PA uses feedback to linearize it, there may be a problem with the feedback loop and the PA may be running open-loop. -- 73 de Brian, WB6RQN Brian Lloyd - brian HYPHEN wb6rqn AT lloyd DOT com _______________________________________________ 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/
