Don¹t understand the post below. The original post starting this thread only asked for definitions. My initial response cited the fact that MIL-STD-461 only allows mode-tuned, not mode-stirred testing. A later post seemed to imply that the higher the frequency, the more paddle positions would be necessary, and my reply cited MIL-STD-461 showing the opposite was the case.
³Oxymoronic² implies an inherent contradiction, don¹t understand to what that refers. And as the original post asked only for definitions, MIL-STD-461 was only brought up to illustrate some technical issues. Ken Javor Phone: (256) 650-5261 From: Bill Owsley <wdows...@yahoo.com> Reply-To: Bill Owsley <wdows...@yahoo.com> Date: Thu, 9 May 2013 12:48:14 -0700 (PDT) To: Ken Javor <ken.ja...@emccompliance.com>, "EMC-PSTC@LISTSERV.IEEE.ORG" <EMC-PSTC@LISTSERV.IEEE.ORG> Subject: Re: Mode-stirred, Mode-tuned, Reverb - what's the difference? I was then and am still the casual observer of reverb testing, but have noticed over the course of a number of conversations on MIL-STD testing there seems to be an oxymoronic appearance to the processes without a detailed definition or explanation of how a particular process came about. And the subject testing in the conversation was not military but involved the imagined physics and geometry of what is happening in the chamber to the EUT, and in order to plan on building a reverb chamber. Now to get back to skewering those darting little waifs of RF hot spots. > > > > > > From: Ken Javor <ken.ja...@emccompliance.com> > To: "EMC-PSTC@LISTSERV.IEEE.ORG" <EMC-PSTC@LISTSERV.IEEE.ORG> > Sent: Monday, April 29, 2013 12:23 AM > Subject: Re: Mode-stirred, Mode-tuned, Reverb - what's the difference? > > > > Re: Mode-stirred, Mode-tuned, Reverb - what's the difference? > Not obvious to me that the original question was asking for a recommendation; > only a definition. > > That being said, the below seems to be somewhat at odds with MIL-STD-461 > paddle position requirements. Table VIII in that standard requires the > following number of paddle positions as a function of frequency: > > 200 300 MHz: 50 positions (7.2 degrees per step) > 300 400 MHz: 20 positions (18 degrees per step) > 400 600 MHz: 16 positions (22.5 degrees per step) > 600+ MHz: 12 positions (30 degrees per step) > > Perhaps I am misinterpreting the previous post (below). > > Ken Javor > Phone: (256) 650-5261 > > > > From: Bill Owsley <wdows...@yahoo.com> > Reply-To: Bill Owsley <wdows...@yahoo.com> > Date: Sun, 28 Apr 2013 19:22:49 -0700 (PDT) > To: Ken Javor <ken.ja...@emccompliance.com>, "EMC-PSTC@LISTSERV.IEEE.ORG" > <EMC-PSTC@LISTSERV.IEEE.ORG> > Subject: Re: Mode-stirred, Mode-tuned, Reverb - what's the difference? > > The debate amongst the proponents that I heard concerned the concept or idea > of matching, or not , test program cycle time with paddle cycle time. The > tuned folks argued that the paddle should stop at each step for a program > cycle time, then there was the debate over how big is each step. At high > freq's the step are necessarily small to account for the wavelength leveraged > over the distance from the paddle to the EUT and what sort of variation might > be expected. > And the statistical study of a chamber showing variation on paddle angle per > frequency. > Verses the other guys that argued since the paddle rate was some speed, pick > one. And the exercise program was one rate. There is just the choice of > picking a rotation rate, assuming that is a controllable variable, that was > some divisor or multiplier like 'pi' since it never repeats. > Just stop and back up to remember what the concept of a reverb chamber was all > about. > If each freq or paddle positionwas to be investigated alone, why change from > the previous? > The intent was to increase speed and retain some degree of accuracy. > > >> >> >> >> >> >> From: Ken Javor <ken.ja...@emccompliance.com> >> To: EMC-PSTC@LISTSERV.IEEE.ORG >> Sent: Sunday, April 28, 2013 12:34 PM >> Subject: Re: Mode-stirred, Mode-tuned, Reverb - what's the difference? >> >> >> >> Re: Mode-stirred, Mode-tuned, Reverb - what's the difference? >> One can mode-stir or mode-tune a reverb chamber. Mode-stirring is continuous >> the paddle never ceases movement and mode tuning utilizes a stepping >> movement, holding each mode for a specific time period to allow assessment of >> susceptibility. >> >> Can¹t speak for others, but MIL-STD-461 only allows mode-tuning. >> >> Ken Javor >> Phone: (256) 650-5261 >> >> >> >> From: Pat Lawler <pat.law...@verizon.net> >> Date: Sun, 28 Apr 2013 07:38:25 -0700 >> To: <EMC-PSTC@LISTSERV.IEEE.ORG> >> Subject: Mode-stirred, Mode-tuned, Reverb - what's the difference? >> >> All, >> >> Over the years, I've come across pictures of test chambers with descriptions >> such as mode-stirred, mode-turned, and reverberation. They seem to look >> similar, with metal walls and rotating metal paddles. >> >> Do these names reference the same basic design, or are they different >> animals? Which ones are used for which type of RF immunity test? >> >> Thanks, >> Pat Lawler >> Teset engineer >> >> - >> ---------------------------------------------------------------- >> >> This message is from the IEEE Product Safety Engineering Society emc-pstc >> discussion list. To post a message to the list, send your e-mail to >> <emc-p...@ieee.org> >> >> All emc-pstc postings are archived and searchable on the web at: >> http://www.ieee-pses.org/emc-pstc.html >> >> Attachments are not permitted but the IEEE PSES Online Communities site at >> http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used >> formats), large files, etc. >> >> Website: http://www.ieee-pses.org/ >> Instructions: http://listserv.ieee.org/request/user-guide.html >> List rules: http://www.ieee-pses.org/listrules.html >> >> For help, send mail to the list administrators: >> Scott Douglas <emcp...@radiusnorth.net> >> Mike Cantwell <mcantw...@ieee.org> >> >> For policy questions, send mail to: >> Jim Bacher <j.bac...@ieee.org> >> David Heald <dhe...@gmail.com> >> >> - >> ---------------------------------------------------------------- >> This message is from the IEEE Product Safety Engineering Society emc-pstc >> discussion list. To post a message to the list, send your e-mail to >> <emc-p...@ieee.org> >> All emc-pstc postings are archived and searchable on the web at: >> http://www.ieee-pses.org/emc-pstc.html >> Attachments are not permitted but the IEEE PSES Online Communities site at >> http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used >> formats), large files, etc. >> Website: http://www.ieee-pses.org/ >> Instructions: http://listserv.ieee.org/request/user-guide.html >> List rules: http://www.ieee-pses.org/listrules.html >> For help, send mail to the list administrators: >> Scott Douglas <emcp...@radiusnorth.net> >> Mike Cantwell <mcantw...@ieee.org> >> For policy questions, send mail to: >> Jim Bacher <j.bac...@ieee.org> >> David Heald <dhe...@gmail.com> >> >> >> >> >> > > - > ---------------------------------------------------------------- > > This message is from the IEEE Product Safety Engineering Society emc-pstc > discussion list. To post a message to the list, send your e-mail to > <emc-p...@ieee.org> > > All emc-pstc postings are archived and searchable on the web at: > http://www.ieee-pses.org/emc-pstc.html > > Attachments are not permitted but the IEEE PSES Online Communities site at > http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used > formats), large files, etc. > > Website: http://www.ieee-pses.org/ > Instructions: http://listserv.ieee.org/request/user-guide.html > List rules: http://www.ieee-pses.org/listrules.html > > For help, send mail to the list administrators: > Scott Douglas <emcp...@radiusnorth.net> > Mike Cantwell <mcantw...@ieee.org> > > For policy questions, send mail to: > Jim Bacher <j.bac...@ieee.org> > David Heald <dhe...@gmail.com> > > - > ---------------------------------------------------------------- > This message is from the IEEE Product Safety Engineering Society emc-pstc > discussion list. To post a message to the list, send your e-mail to > <emc-p...@ieee.org> > All emc-pstc postings are archived and searchable on the web at: > http://www.ieee-pses.org/emc-pstc.html > Attachments are not permitted but the IEEE PSES Online Communities site at > http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used > formats), large files, etc. > Website: http://www.ieee-pses.org/ > Instructions: http://listserv.ieee.org/request/user-guide.html > List rules: http://www.ieee-pses.org/listrules.html > For help, send mail to the list administrators: > Scott Douglas <emcp...@radiusnorth.net> > Mike Cantwell <mcantw...@ieee.org> > For policy questions, send mail to: > Jim Bacher <j.bac...@ieee.org> > David Heald <dhe...@gmail.com> > > > > > - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <emc-p...@ieee.org> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <emcp...@radiusnorth.net> Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher: <j.bac...@ieee.org> David Heald: <dhe...@gmail.com>
