I read in !emc-pstc that Ken Javor <[email protected]> wrote (in <20020119014135.UEWQ10932.femail35.sdc1.sfba.home.com@[65.11.150.27] >) about 'RF Field Uniformity and Antenna location', on Fri, 18 Jan 2002: >I went to the EMC Test Systems website and looked at the 3106 half power >beamwidth: > >http://www.emctest.com/productpage.cfm?model=3106&producttype=Antennas > >At around 850 MHz, it dips to a low of just under 30 degrees, which means >that a 1.5 m square has its edges at the half power point (with the >antenna-EUT spacing of 3 m). So it may just barely work. But if you look >at a log periodic such as the 3144: > >http://www.emctest.com/productpage.cfm?model=3144&producttype=Antennas > >the beamwidth minimum is nearly 50 degrees and you get a more uniform field >intensity. > >The disparity is not as much as my gut reaction. I am used to working at 1 >meter separations and the directionality of the DRG horn is a greater >problem than at three meters.
Thanks, I understand now. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk After swimming across the Hellespont, I felt like a Hero. ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson: [email protected] Dave Heald [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
