> -----Original Message----- > From: Bob Richards [ mailto:b...@toprudder.com] > Sent: Thursday, June 23, 2005 7:06 AM > To: emc-p...@ieee.org > Subject: Re: ??? RE: ??? RE: Near field H-field measurement. > > Ken, > > I believe you are correct. There should be factors for this > loop antenna from Emco that convert the raw reading (in dBuv) > to a magnetic field level (like dBuA/m). > > The spectrum analyzer does NOT read in dBuv/m as he seems to > suggest, it only reads in dBuv or dBm, but some analyzers do > allow factors to be entered so the display will be in useful > units. I prefer not having the analyzer apply factors. Less > chance for errors that way, IMHO. > > Bob Richards, NCT.
EMCO (ETS) shows generic correction factors for the 6502 at: http://www.ets-lindgren.com/productpage.cfm/model/6502/producttype/Antennas They have a pair of charts for correcting the antenna output (in dBuV) to units of electric field (dBuV/m) or magnetic field (dBuA/m). I don't like the practice of a factor for converting loop output voltage directly to dBuV/m, because it is making the assumption of far-field conditions (377 ohms, and an H-field to E-field conversion of +51.5 dB). The 6502 is a shielded loop, and responds to the H-field, no matter where you place it. You can accurately derive the E-field from the H-field only when you are confident of far-field conditions. Ed Price ed.pr...@cubic.com WB6WSN NARTE Certified EMC Engineer & Technician Electromagnetic Compatibility Lab Cubic Defense Applications San Diego, CA USA 858-505-2780 (Voice) 858-505-1583 (Fax) Military & Avionics EMC Is Our Specialty ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/listserv/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
