Derek, I always do cables individually. However, for our chamber emissions setup, I also run the insertion loss from end-to-end which includes all cables and the bulkhead adapter. I'll have to look at CISPR 16 and LAB 34. I've generally tried to avoid MU if at all possible. :-) I like the "nothing" as well. Bob R.
--- On Mon, 2/7/11, Derek Walton <[email protected]> wrote: From: Derek Walton <[email protected]> Subject: Re: In-house cable calibrations -VSWR To: [email protected], [email protected] Date: Monday, February 7, 2011, 3:32 PM Hi Bob, I guess it depends.... First, ask why you would use VSWR data. My guess is that it would be for your MU calculations. So if you have a line in your MU budget for this mismatch, you should really have it. Off the top of my head I can't remember if the tables in CISPR 16 or LAB 34 have a line item for it: if it does, then you should really have it, if it doesnt, then why bother? If you don't have MU budgets, why bother? Do you have several cables you join together and just do 1 VSWR, or all separate: do you include the bulkhead coupler? I was on an assessment just recently where this discussion came up. Frankly, I don't see why cables ( a gain/loss block ) are treated any differently from attenuators or amplifiers ( also gain/loss blocks ). In this assessment, I believe we decided cables were NOT treated the same as amps and attenuators: I do not agree with this philosophy, it should be all or nothing. I kinda like the nothing best :-) My 15 cents worth. Cheers, Derek Walton -----Original Message----- From: Bob Richards <[email protected]> To: [email protected] Sent: Mon, Feb 7, 2011 2:15 pm Subject: In-house cable calibrations -VSWR In the past I have done cable calibrations in-house. (Ok, "verifications", not "calibrations" :-) I've only done simple insertion loss, usually with a signal generator and power meter. It has never been an issue before. However, just recently, it has been suggested that the VSWR should be measured as well. So, if you have an opinion on the subject, I would like to hear it. Thanks in advance, Bob R. - ---------------------------------------------------------------- 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 <[email protected] <http://us.mc11.mail yahoo.com/mc/[email protected]> > All emc-pstc postings are archived and searchable on the web at http://product-compliance.oc.ieee.org/ Graphics (in well-used formats), large files, etc. can be posted to that URL. 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 <[email protected] <http://us.mc11.mail.yahoo.com/mc/[email protected]> > Mike Cantwell <[email protected] <htt ://us.mc11.mail.yahoo.com/mc/[email protected]> > For policy questions, send mail to: Jim Bacher <[email protected] <http:// s.mc11.mail.yahoo.com/mc/[email protected]> > David Heald <[email protected] <http:// s.mc11.mail.yahoo.com/mc/[email protected]> > - ---------------------------------------------------------------- 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 <[email protected]> All emc-pstc postings are archived and searchable on the web at http://product-compliance.oc.ieee.org/ Graphics (in well-used formats), large files, etc. can be posted to that URL. 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 <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher <[email protected]> David Heald <[email protected]>
