Re: case of units
I don't believe Ed was wrong at all, in most any case I can think of he was precisely correct. Whether you use 10 log () or 20 log () depends upon whether the ratio that is the argument of the log function is power or something related to power by a square-law relationship. The most obvious of these are voltage and current. But when impedance is used to get from a voltage to a current or vice versa, then the basic equation is V = IR and since both V & I are 20 log quantities, impedance must be as well. Hence any equation in which capacitance or inductance are used to get at reactances must also follow a 20 log dependency. This is the basis of impedance paper, and also any of you who have ever used a current probe characterized by transfer impedance also know that the impedance of the probe in dB Ohms is 20 log (Impedance in Ohms). on 6/27/02 9:54 AM, Price, Ed at ed.pr...@cubic.com wrote: > > I proposed the capacitance unit of dBF with tongue firmly planted in cheek. > And yes, maybe 10 Log is more proper than 20 Log (hey, 44.5 dB error is as > close as I get sometimes). > > OTOH, the more I think about it, resistance, inductance and capacitance > values in practical circuitry exist over such a wide numeric range that > perhaps a logarithmic scale would be appropriate. 470 k Ohms, 0.47 M Ohms, > 470,000 Ohms are all 113 db Ohm. > > Not to mention that the US national debt is currently only about 128 dB$ > (yes, I did use 10 Log here, because everyone agrees that money is power) > at: > http://www.brillig.com/debt_clock/ > > Ed > > > Ed Price > ed.pr...@cubic.com > Electromagnetic Compatibility Lab > Cubic Defense Systems > San Diego, CA USA > 858-505-2780 (Voice) > 858-505-1583 (Fax) > Military & Avionics EMC Services Is Our Specialty > Shake-Bake-Shock - Metrology - Reliability Analysis > > > >> -Original Message- >> From: Wan Juang Foo [mailto:f...@np.edu.sg] >> Sent: Wednesday, June 26, 2002 7:00 PM >> To: emc-p...@majordomo.ieee.org >> Subject: RE: case of units >> >> >> >> >> Dear all, >> >> I wonder if dBF is 20 log C or 10 log C ? >> >> My personal guess is that if VA= V² Z and Z=sC then I suppose >> dBF should >> carry a 10 log tag. Could Ed be 44.5 dB off the mark? >> Just my 2 ¢ worth. (On an aside, I must say this hidden >> character thingy >> is rather fascinating , cents is [Num Lock] ) >> :-) >> Tim Foo >> >> > SNIP >> >>> -Original Message- >>> From: Nick Rouse [mailto:nick.ro...@btopenworld.com] >>> Sent: Wednesday, June 26, 2002 1:14 PM >>> To: emc >>> Subject: Re:case of units >> >>> Millifarad sized capacitors are now common >>> and I have seen one instance of one marked mF. >>> With the new double layer supercaps multifarad >>> rated capacitors are also available and >>> someone is marketing a 28kF capacitor >>> or if you prefer 0.028MF >>> >>> Nick Rouse >>> >> >> >> Wow, an 89 dBF capacitor! >> >> ED >> >> > > --- > 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: > majord...@ieee.org > with the single line: > unsubscribe emc-pstc > > For help, send mail to the list administrators: > Ron Pickard: emc-p...@hypercom.com > Dave Heald: davehe...@attbi.com > > 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://ieeepstc.mindcruiser.com/ > Click on "browse" and then "emc-pstc mailing list" > -- 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com 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://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
RE: case of units
I proposed the capacitance unit of dBF with tongue firmly planted in cheek. And yes, maybe 10 Log is more proper than 20 Log (hey, 44.5 dB error is as close as I get sometimes). OTOH, the more I think about it, resistance, inductance and capacitance values in practical circuitry exist over such a wide numeric range that perhaps a logarithmic scale would be appropriate. 470 k Ohms, 0.47 M Ohms, 470,000 Ohms are all 113 db Ohm. Not to mention that the US national debt is currently only about 128 dB$ (yes, I did use 10 Log here, because everyone agrees that money is power) at: http://www.brillig.com/debt_clock/ Ed Ed Price ed.pr...@cubic.com Electromagnetic Compatibility Lab Cubic Defense Systems San Diego, CA USA 858-505-2780 (Voice) 858-505-1583 (Fax) Military & Avionics EMC Services Is Our Specialty Shake-Bake-Shock - Metrology - Reliability Analysis >-Original Message- >From: Wan Juang Foo [mailto:f...@np.edu.sg] >Sent: Wednesday, June 26, 2002 7:00 PM >To: emc-p...@majordomo.ieee.org >Subject: RE: case of units > > > > >Dear all, > >I wonder if dBF is 20 log C or 10 log C ? > >My personal guess is that if VA= V² Z and Z=sC then I suppose >dBF should >carry a 10 log tag. Could Ed be 44.5 dB off the mark? >Just my 2 ¢ worth. (On an aside, I must say this hidden >character thingy >is rather fascinating , cents is [Num Lock] ) >:-) >Tim Foo > > SNIP > >>-Original Message- >>From: Nick Rouse [mailto:nick.ro...@btopenworld.com] >>Sent: Wednesday, June 26, 2002 1:14 PM >>To: emc >>Subject: Re:case of units > >>Millifarad sized capacitors are now common >>and I have seen one instance of one marked mF. >>With the new double layer supercaps multifarad >>rated capacitors are also available and >>someone is marketing a 28kF capacitor >>or if you prefer 0.028MF >> >>Nick Rouse >> > > >Wow, an 89 dBF capacitor! > >ED > > --- 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com 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://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
RE: case of units
Dear all, I wonder if dBF is 20 log C or 10 log C ? My personal guess is that if VA= V² Z and Z=sC then I suppose dBF should carry a 10 log tag. Could Ed be 44.5 dB off the mark? Just my 2 ¢ worth. (On an aside, I must say this hidden character thingy is rather fascinating , cents is [Num Lock] ) :-) Tim Foo "Price, Ed" To: emc Sent by: cc: (bcc: Wan Juang Foo/ece/staff/npnet) owner-emc-pstc@majordo Subject: RE: case of units mo.ieee.org 06/27/02 07:20 AM Please respond to "Price, Ed" >-Original Message- >From: Nick Rouse [mailto:nick.ro...@btopenworld.com] >Sent: Wednesday, June 26, 2002 1:14 PM >To: emc >Subject: Re:case of units >Millifarad sized capacitors are now common >and I have seen one instance of one marked mF. >With the new double layer supercaps multifarad >rated capacitors are also available and >someone is marketing a 28kF capacitor >or if you prefer 0.028MF > >Nick Rouse > Wow, an 89 dBF capacitor! ED --- 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com 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://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
RE: case of units
>-Original Message- >From: Nick Rouse [mailto:nick.ro...@btopenworld.com] >Sent: Wednesday, June 26, 2002 1:14 PM >To: emc >Subject: Re:case of units > > > > >If you want to stop mu being translated back to m don't insert it >from the symbols font. Most normal windows fonts have it as >a character. Put the num lock on the keyboard on, hold down the >alt key and type on the number pad >0181 >other useful codes are >degrees 0176 >plus or minus 0177 >half 0189 >quarter 0188 >squared 0178 >cubed 0179 > >Millifarad sized capacitors are now common >and I have seen one instance of one marked mF. >With the new double layer supercaps multifarad >rated capacitors are also available and >someone is marketing a 28kF capacitor >or if you prefer 0.028MF > >Nick Rouse > Wow, an 89 dBF capacitor! ED Ed Price ed.pr...@cubic.com Electromagnetic Compatibility Lab Cubic Defense Systems San Diego, CA USA 858-505-2780 (Voice) 858-505-1583 (Fax) Military & Avionics EMC Services Is Our Specialty Shake-Bake-Shock - Metrology - Reliability Analysis --- 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com 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://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
RE: case of units
Spot on Tom! I have always stuck with lower case k - even when entering values in a database which is all in upper case! Of course, this scientific correctness lasts only a few days before someone spots my wonderful room temperature components, dips them in liquid nitrogen and the next thing I know they are all temperatures in Kelvin (10K)!! I will admit though, to not putting any space between the number and the unit, but I remember the look my physics teacher used to give us if someone had the misfortune to call the unit "degrees Kelvin" instead of plain "Kelvin". For your information http://physics.nist.gov/cuu/Units/ has it all. Regards - Chris -Original Message- From: T.Sato [SMTP:vef00...@nifty.ne.jp] Sent: Tuesday, June 25, 2002 3:39 AM To: emc-p...@majordomo.ieee.org Subject: Re: case of units On Mon, 24 Jun 2002 11:17:18 -0700, "Robert Macy" wrote: > Still use KHz > > For me it's a logical carrier over from > small letter = small value > capital letter = large value SI units are originally described in "The International System of Units" (strictly, in French) from BIPM, and it states kilo is "k", not "K". Although they are very rarely used these days, "h" (hecto = 10^2) and "da" (deca = 10^1) are written in small letters, too. Regards, Tom -- Tomonori Sato URL: http://member.nifty.ne.jp/tsato/ --- 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com 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://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list" This e-mail has been scanned for all viruses by Star Internet. The service is powered by MessageLabs. For more information on a proactive anti-virus service working around the clock, around the globe, visit: http://www.star.net.uk This e-mail has been scanned for all viruses by Star Internet. The service is powered by MessageLabs. For more information on a proactive anti-virus service working around the clock, around the globe, visit: http://www.star.net.uk --- 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com 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://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
Re: case of units
Dear all, The capital W is probably a font translation error that was not spotted. I had much heart ache over this whenever I print something in a different computer. I have had much experience with entire documents that have the greek lower case m (micro=u=greak mu) being subsituted for a plain lower case m etc... It is very frustrating. This bring to mind a similar and more widely use practice in marking electrolytic capacitors e.g. 10mfd instead of 10uF. It is oblivious to the experienced engineer, mfd is read as micro Farad knowing that the mili Farad component is probably the size of a chair! I wonder if this will catch any technical types by surprise. :-) Tim Foo Cortland Richmond <72146.373@compuserve. To: "Brent DeWitt" , ieee pstc list com> Sent by: cc: (bcc: Wan Juang Foo/ece/staff/npnet) owner-emc-pstc@majordo Subject: Re: case of units mo.ieee.org 06/25/02 01:53 PM Please respond to Cortland Richmond Another "interesting" thing -- not the same as this -- is what happens to the upper-case Omega some documents use instead of spelling out "ohms;" some software turns it into "W." I could have SWORN I'd see a 1000 W resistor on a modem card! Cortland --- 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com 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://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
Re: case of units
Another "interesting" thing -- not the same as this -- is what happens to the upper-case Omega some documents use instead of spelling out "ohms;" some software turns it into "W." I could have SWORN I'd see a 1000 W resistor on a modem card! Cortland --- 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com 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://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
Re: case of units
On Mon, 24 Jun 2002 11:17:18 -0700, "Robert Macy" wrote: > Still use KHz > > For me it's a logical carrier over from > small letter = small value > capital letter = large value SI units are originally described in "The International System of Units" (strictly, in French) from BIPM, and it states kilo is "k", not "K". Although they are very rarely used these days, "h" (hecto = 10^2) and "da" (deca = 10^1) are written in small letters, too. Regards, Tom -- Tomonori Sato URL: http://member.nifty.ne.jp/tsato/ --- 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com 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://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
Re: case of units
Don, you're probably right in that it went the other way. My super and I had quite a laugh about it till some poor purchaser told us what was up. - Doug McKean --- 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com 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://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
Re: case of units
Doug- Are you sure you don't mean "M" used as a multiplier that means 1000? I have seen some old radio schematics (pre-WWII) that had 50 M and 100 M resistors (5 and 10 ohms). Values greater than 1 million ohms were given as "2 Meg", etc. Don Borowski, PE Schweitzer Engineering Labs Pullman, WA "Doug McKean" on 06/24/2002 12:33:24 PM Please respond to "Doug McKean" To: "EMC-PSTC Discussion Group" cc:(bcc: Don Borowski/SEL) Subject: Re: case of units Just don't talk to some old purchasing types about "k". It doesn't mean base 1,000 in purchasing land. More like base 1,000,000. I ordered some resistors in qty = 1k. It got kicked back to my supervisor because (1) when I multiplied out the final cost, it was wrong and (2) there was no justification for buying one million resistors. Regards, Doug McKean --- 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com 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://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list" This e-mail may contain SEL confidential information. The opinions expressed are not necessarily those of SEL. Any unauthorized disclosure, distribution or other use is prohibited. If you received this e-mail in error, please notify the sender, permanently delete it, and destroy any printout. Thank you. --- 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com 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://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
Re: case of units
Robert and EMC-PSTC, According to some books of physics (e.g., Halliday and Resnick) and Web pages concerning measurements: http://www.chemie.fu-berlin.de/chemistry/general/si_en.html#prefixes The right usage of "kilohertz" is "kHz", and not "KHz". Best Regards Muriel - Original Message - From: "Robert Macy" To: "Price, Ed" ; Sent: Monday, June 24, 2002 3:17 PM Subject: Re: case of units > > Still use KHz > > For me it's a logical carrier over from > small letter = small value > capital letter = large value > >mOhm means milli Ohm NOT mega Ohm >mHz is milliHertz >KHz is kilo Hertz (note magnifier is larger than one) >MHz is megaHertz > and so on > > - Robert - > >Robert A. Macy, PEm...@california.com >408 286 3985 fx 408 297 9121 >AJM International Electronics Consultants >619 North First St, San Jose, CA 95112 > > > -Original Message- > From: Price, Ed > To: emc-p...@majordomo.ieee.org > Date: Monday, June 24, 2002 8:24 AM > Subject: RE: case of units > > > > > > > > > >>-Original Message- > >>From: Brent DeWitt [mailto:bdew...@ix.netcom.com] > >>Sent: Sunday, June 23, 2002 7:04 PM > >>To: emc-p...@majordomo.ieee.org > >>Subject: case of units > >> > >> > >> > >>I've always found it interesting that the small "k" is the > >>only lower case > >>letter used for multipliers greater than unity. I presume it > >>is because the > >>temperature folks got there first with Lord Kelvin's initial. Too bad > >>really since "kilo" has a linguistic meaning for numbers and > >>Kelvin is just > >>a name. Also rather interesting that we have no trouble using > >>"G" for both > >>Giga and Gauss. > >> > >>Just Sunday evening thoughts. > >> > >>Brent DeWitt > > > > > >Brent: > > > >For years, I had always written kiloHertz as KHz. Then, as a hirling, I > >bumped up against the Information Technology Group at General Dynamics > >Electronics Division. I noticed that all my text came back using "kHz." > >After a few cycles of this, I decided to follow up on the cause. I found > >that they worked to a bureaucratic "style manual", which dictated the style > >for abbreviations and technical terms. I had the temerity to ask who wrote > >the style manual, and why KHz was rendered as kHz. They finally produced a > >Mil-Std, which had a list of acronyms and special terms. And, there on the > >list, was "kHz"! No explanation, just "kHz". So I asked them if maybe the > >Mil-Std was just a typo error, and that shouldn't we allow logic to > prevail? > >No, because if they did that, someone might think the abbreviation actually > >meant "degrees Kelvin Hertz". They won. > > > >Lately, after many more years of continuing to personally use KHz (and > >having re-educated my MS Word about my preference), I find that I am > >wearying of the explanations, and have started to use kHz. Yup, they won. > > > >Ed > > > > > > > > > >Ed Price > >ed.pr...@cubic.com > >Electromagnetic Compatibility Lab > >Cubic Defense Systems > >San Diego, CA USA > >858-505-2780 (Voice) > >858-505-1583 (Fax) > >Military & Avionics EMC Services Is Our Specialty > >Shake-Bake-Shock - Metrology - Reliability Analysis > > > >--- > >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: > > majord...@ieee.org > >with the single line: > > unsubscribe emc-pstc > > > >For help, send mail to the list administrators: > > Ron Pickard: emc-p...@hypercom.com > > Dave Heald: davehe...@attbi.com > > > >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://ieeepstc.mindcruiser.com/ > >Click on "browse" and then "emc-pstc mailing list" > > > --- > This message
Re: case of units
OK, I'll bite. If KHz means kilohertz, what does kHz mean? Don Borowski, PE Schweitzer Enginering Labs Pullman, WA "Robert Macy" on 06/24/2002 11:17:18 AM Please respond to "Robert Macy" To: "Price, Ed" , emc-p...@majordomo.ieee.org cc:(bcc: Don Borowski/SEL) Subject: Re: case of units Still use KHz For me it's a logical carrier over from small letter = small value capital letter = large value mOhm means milli Ohm NOT mega Ohm mHz is milliHertz KHz is kilo Hertz (note magnifier is larger than one) MHz is megaHertz and so on - Robert - Robert A. Macy, PEm...@california.com 408 286 3985 fx 408 297 9121 AJM International Electronics Consultants 619 North First St, San Jose, CA 95112 -Original Message- From: Price, Ed To: emc-p...@majordomo.ieee.org List-Post: emc-pstc@listserv.ieee.org Date: Monday, June 24, 2002 8:24 AM Subject: RE: case of units > > > >>-Original Message- >>From: Brent DeWitt [mailto:bdew...@ix.netcom.com] >>Sent: Sunday, June 23, 2002 7:04 PM >>To: emc-p...@majordomo.ieee.org >>Subject: case of units >> >> >> >>I've always found it interesting that the small "k" is the >>only lower case >>letter used for multipliers greater than unity. I presume it >>is because the >>temperature folks got there first with Lord Kelvin's initial. Too bad >>really since "kilo" has a linguistic meaning for numbers and >>Kelvin is just >>a name. Also rather interesting that we have no trouble using >>"G" for both >>Giga and Gauss. >> >>Just Sunday evening thoughts. >> >>Brent DeWitt > > >Brent: > >For years, I had always written kiloHertz as KHz. Then, as a hirling, I >bumped up against the Information Technology Group at General Dynamics >Electronics Division. I noticed that all my text came back using "kHz." >After a few cycles of this, I decided to follow up on the cause. I found >that they worked to a bureaucratic "style manual", which dictated the style >for abbreviations and technical terms. I had the temerity to ask who wrote >the style manual, and why KHz was rendered as kHz. They finally produced a >Mil-Std, which had a list of acronyms and special terms. And, there on the >list, was "kHz"! No explanation, just "kHz". So I asked them if maybe the >Mil-Std was just a typo error, and that shouldn't we allow logic to prevail? >No, because if they did that, someone might think the abbreviation actually >meant "degrees Kelvin Hertz". They won. > >Lately, after many more years of continuing to personally use KHz (and >having re-educated my MS Word about my preference), I find that I am >wearying of the explanations, and have started to use kHz. Yup, they won. > >Ed > > > > >Ed Price >ed.pr...@cubic.com >Electromagnetic Compatibility Lab >Cubic Defense Systems >San Diego, CA USA >858-505-2780 (Voice) >858-505-1583 (Fax) >Military & Avionics EMC Services Is Our Specialty >Shake-Bake-Shock - Metrology - Reliability Analysis > >--- >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: > majord...@ieee.org >with the single line: > unsubscribe emc-pstc > >For help, send mail to the list administrators: > Ron Pickard: emc-p...@hypercom.com > Dave Heald: davehe...@attbi.com > >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://ieeepstc.mindcruiser.com/ >Click on "browse" and then "emc-pstc mailing list" --- 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com 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://ieeepstc.mindcrui
Re: case of units
Just don't talk to some old purchasing types about "k". It doesn't mean base 1,000 in purchasing land. More like base 1,000,000. I ordered some resistors in qty = 1k. It got kicked back to my supervisor because (1) when I multiplied out the final cost, it was wrong and (2) there was no justification for buying one million resistors. Regards, Doug McKean --- 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com 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://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
Re: case of units
Still use KHz For me it's a logical carrier over from small letter = small value capital letter = large value mOhm means milli Ohm NOT mega Ohm mHz is milliHertz KHz is kilo Hertz (note magnifier is larger than one) MHz is megaHertz and so on - Robert - Robert A. Macy, PEm...@california.com 408 286 3985 fx 408 297 9121 AJM International Electronics Consultants 619 North First St, San Jose, CA 95112 -Original Message- From: Price, Ed To: emc-p...@majordomo.ieee.org List-Post: emc-pstc@listserv.ieee.org Date: Monday, June 24, 2002 8:24 AM Subject: RE: case of units > > > >>-Original Message- >>From: Brent DeWitt [mailto:bdew...@ix.netcom.com] >>Sent: Sunday, June 23, 2002 7:04 PM >>To: emc-p...@majordomo.ieee.org >>Subject: case of units >> >> >> >>I've always found it interesting that the small "k" is the >>only lower case >>letter used for multipliers greater than unity. I presume it >>is because the >>temperature folks got there first with Lord Kelvin's initial. Too bad >>really since "kilo" has a linguistic meaning for numbers and >>Kelvin is just >>a name. Also rather interesting that we have no trouble using >>"G" for both >>Giga and Gauss. >> >>Just Sunday evening thoughts. >> >>Brent DeWitt > > >Brent: > >For years, I had always written kiloHertz as KHz. Then, as a hirling, I >bumped up against the Information Technology Group at General Dynamics >Electronics Division. I noticed that all my text came back using "kHz." >After a few cycles of this, I decided to follow up on the cause. I found >that they worked to a bureaucratic "style manual", which dictated the style >for abbreviations and technical terms. I had the temerity to ask who wrote >the style manual, and why KHz was rendered as kHz. They finally produced a >Mil-Std, which had a list of acronyms and special terms. And, there on the >list, was "kHz"! No explanation, just "kHz". So I asked them if maybe the >Mil-Std was just a typo error, and that shouldn't we allow logic to prevail? >No, because if they did that, someone might think the abbreviation actually >meant "degrees Kelvin Hertz". They won. > >Lately, after many more years of continuing to personally use KHz (and >having re-educated my MS Word about my preference), I find that I am >wearying of the explanations, and have started to use kHz. Yup, they won. > >Ed > > > > >Ed Price >ed.pr...@cubic.com >Electromagnetic Compatibility Lab >Cubic Defense Systems >San Diego, CA USA >858-505-2780 (Voice) >858-505-1583 (Fax) >Military & Avionics EMC Services Is Our Specialty >Shake-Bake-Shock - Metrology - Reliability Analysis > >--- >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: > majord...@ieee.org >with the single line: > unsubscribe emc-pstc > >For help, send mail to the list administrators: > Ron Pickard: emc-p...@hypercom.com > Dave Heald: davehe...@attbi.com > >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://ieeepstc.mindcruiser.com/ >Click on "browse" and then "emc-pstc mailing list" --- 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com 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://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
RE: case of units
>-Original Message- >From: Brent DeWitt [mailto:bdew...@ix.netcom.com] >Sent: Sunday, June 23, 2002 7:04 PM >To: emc-p...@majordomo.ieee.org >Subject: case of units > > > >I've always found it interesting that the small "k" is the >only lower case >letter used for multipliers greater than unity. I presume it >is because the >temperature folks got there first with Lord Kelvin's initial. Too bad >really since "kilo" has a linguistic meaning for numbers and >Kelvin is just >a name. Also rather interesting that we have no trouble using >"G" for both >Giga and Gauss. > >Just Sunday evening thoughts. > >Brent DeWitt Brent: For years, I had always written kiloHertz as KHz. Then, as a hirling, I bumped up against the Information Technology Group at General Dynamics Electronics Division. I noticed that all my text came back using "kHz." After a few cycles of this, I decided to follow up on the cause. I found that they worked to a bureaucratic "style manual", which dictated the style for abbreviations and technical terms. I had the temerity to ask who wrote the style manual, and why KHz was rendered as kHz. They finally produced a Mil-Std, which had a list of acronyms and special terms. And, there on the list, was "kHz"! No explanation, just "kHz". So I asked them if maybe the Mil-Std was just a typo error, and that shouldn't we allow logic to prevail? No, because if they did that, someone might think the abbreviation actually meant "degrees Kelvin Hertz". They won. Lately, after many more years of continuing to personally use KHz (and having re-educated my MS Word about my preference), I find that I am wearying of the explanations, and have started to use kHz. Yup, they won. Ed Ed Price ed.pr...@cubic.com Electromagnetic Compatibility Lab Cubic Defense Systems San Diego, CA USA 858-505-2780 (Voice) 858-505-1583 (Fax) Military & Avionics EMC Services Is Our Specialty Shake-Bake-Shock - Metrology - Reliability Analysis --- 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com 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://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
case of units
I've always found it interesting that the small "k" is the only lower case letter used for multipliers greater than unity. I presume it is because the temperature folks got there first with Lord Kelvin's initial. Too bad really since "kilo" has a linguistic meaning for numbers and Kelvin is just a name. Also rather interesting that we have no trouble using "G" for both Giga and Gauss. Just Sunday evening thoughts. Brent DeWitt -Original Message- From: owner-emc-p...@majordomo.ieee.org [mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of bogdan matoga Sent: Saturday, June 22, 2002 6:55 PM To: Robert Wilson Cc: TM66; emc-p...@majordomo.ieee.org Subject: Re: SI Unit for volume Bob: When you go for SI then please stay with the convention, i.e. kilowatt is abbreviated as kW and not KW. We are hopefully beyond the time when MAmp was supposed to mean milliampere. Regards, Bogdan. Click on "browse" and then "emc-pstc mailing list" --- 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com 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://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
