Incorrect. A dB is a dB. 3 dB down is half power but 70.7% voltage. 6 dB down is 1/4 power, or one half voltage or current.
on 8/31/03 10:42 AM, [email protected] at [email protected] wrote: >> > A few basics: If we are talking about power points (no software puns > intended) then it is the 3 db points. If we are taking about voltage (or > current) points then it is the 6 db points. As the professors would say, > it is left to the student to prove that 3 dbm = 6 dbv through the formula > P = EE/R. > QED? > >> My understanding is that it is the 6 dB points which are cited as the >> bandwidth. I'm not up on CISPR 16 but to entirely specify the bandwidth >> the 60 dB down points are also specified. The slope you get from the 6 >> dB to the 60 dB points is called the shape factor. >>> From: "Charles Grasso" <[email protected]> >>> Reply-To: "Charles Grasso" <[email protected]> >>> Date: Thu, 28 Aug 2003 07:06:13 -0700 >>> To: "Emc-Pstc" <[email protected]> >>> Subject: Q. on Res Bandwith performace traceabiity >>> >>> >>> Greetings: >>> >>> Does anyone know if the Resolution Bandwidth >>> filter performance is tracable to a given standard >>> and which standard that might be? >>> >>> I was wondering if the rool-off after the 3dB points >>> is specificed as a standard for ALL analysers. >>> >>> I am assuming that the anaswer is Yes as chaos >>> would reign!! >>> >>> ------------------------------------------- >>> 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: >>> Ron Pickard: [email protected] >>> Dave Heald: [email protected] >>> >>> For policy questions, send mail to: >>> Richard Nute: [email protected] >>> Jim Bacher: [email protected] >>> >>> Archive is being moved, we will announce when it is back on-line. All >>> emc-pstc postings are archived and searchable on the web at: >>> http://www.ieeecommunities.org/emc-pstc >>> >> >> >> ------------------------------------------- >> 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: >> Ron Pickard: [email protected] >> Dave Heald: [email protected] >> >> For policy questions, send mail to: >> Richard Nute: [email protected] >> Jim Bacher: [email protected] >> >> Archive is being moved, we will announce when it is back on-line. >> All emc-pstc postings are archived and searchable on the web at: >> http://www.ieeecommunities.org/emc-pstc > > > -- Ken Javor EMC Compliance Huntsville, Alabama 256/650-5261 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: Ron Pickard: [email protected] Dave Heald: [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
