It's not so much a phase shift we're after, but a 90 deg. delay at the center frequency.
I'm very much interested in this converstation, and will go back to lurking. ----- Original Message ----- From: "henkkeppel" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Tuesday, May 13, 2008 5:59 PM Subject: [softrock40] Re: harmonic/oversampling?? > Well this is a good idea, use two simple quad diode mixers. > I wrote before in thse columns that I tried this in the sixties of > the former century with Germanium diode quads but these diodes were > not fast enough then, nor were the Si ones. I selected them on equal > voltage on conducting because that determined the carrier suppression. > The 90 degrees phase shift is on VHF much easier obtainable then on > HF. Just take a quarter wave coaxial cable. Take into account the > velocity factor, so about 1ft+. And with the now available thin > coaxial cable it will be much smaller then with RG58 or59 of those > days. We used a griddipper to determine the quarter wave. > For transmission we also needed a 90 degrees shift between the 2 > audio signals. That was very difficult and was realised with a > complex RC filter with many poles and zeroes of non standard values. > If I had enough time I would give it a try. ------------------------------------ Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/softrock40/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/softrock40/join (Yahoo! ID required) <*> To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
