>I guess my point is, do you know what your passband is in your >radio. Are the 3 db points really at 300 and 2700 Hz? Are there >any fluctuations at other frequencies in the passband? What about >phase variances throughout the passband?
I have made measurements on my IC-746. I set the RX filter to 3 KHz smooth. The response curve is at http://home.comcast.net/~mdmiller7/im3/rx_smooth.jpg I had to use a trend line because I could not take an infinite number of points with this test setup, but the 3 dB bandwidth was 3.055kHz, Setting this same filter to sharp gave the repose at http://home.comcast.net/~mdmiller7/im3/rx_sharp.jpg .The 3 dB bandwidth was 3.087kHz. The receive side seemed pretty smooth, the transmit side was a bit bumpy. The 746 pro has 3 transmit bandwidths, wide, medium, and narrow. The response curve for wide is at http://home.comcast.net/~mdmiller7/im3/tx_wide.jpg . The 3 dB bandwidth was 2.640kHz. As far as intermod goes, this transmitter's linearity in my opinion is acceptable at 40 to 50 watts. I ran a two tone test at 100W PEP which is shown at http://home.comcast.net/~mdmiller7/im3/746PRO100W.jpg . At 50 watts the display is at http://home.comcast.net/~mdmiller7/im3/746PRO50W.jpg , and at 40 watts http://home.comcast.net/~mdmiller7/im3/746PRO40W.jpg . I need to find a way to show group delay, I am working on that now. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/digitalradio/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/
