5% of 50 watts is not 5 watts. 73, Mike
On 12/9/2011 10:32 AM, Eugene Balinski wrote: > > From what I understand, the meter is rated at 5% of the > **full scale** rating according to Bird. Full scale > rating, is the rating on the slug. > > That would mean that for a meter with a 100W slug, your > accuracy is +/- 5W (5%). So, if your wattmeter is reading > 50W, the actual RF power could actually be 45 or 55 W.... > > 73 > K1NR > > > On Fri, 09 Dec 2011 09:08:55 -0500 > Mike<[email protected]> wrote: >> Wait. >> >> Using a 100W slug, if you get a reading of 100 watts, the >> real power would be between >> 95 and 105 watts, right? >> If you get a reading of 50 watts the real power would >> fall in a range of less than 45 >> to 55 watts? >> >> Not if the 5% at full scale is the best accuracy. Or did >> I misunderstand what you said? >> >> 73, Mike NF4L >> >> >> On 12/8/2011 11:59 PM, Eugene Balinski wrote: >>> The accuracy of Bird elements is typically +/- 5% of >> the >>> full scale value. For a 100 W Slug, that is +/- 5 >> Watts. >>> So theoretically speaking, with 5W in, and 0 >> registered >>> on the meter, the meter is still within its rated >> accuracy. >>> >>> Additionally on the model 43 meter, there is meter >> scale >>> end compression. To get the most accurate reading, one >>> would want to have the 5W reading at the middle of the >>> meter range, which means that one would want a 10W >> slug. >>> Unfortunately I do not believe that Bird makes a 10W >> HF >>> slug any more. Perhaps they need an Elecraft W2 ?? >>> >>> 73 >>> K1NR >>> >>> >>> On Thu, 8 Dec 2011 16:47:27 -0600 >>> Nate Bargmann<[email protected]> wrote: >>>>> From my experience, trying to measure 5W with a 100W >>>> element leads to >>>> very inaccurate readings. The Bird is most accurate >> when >>>> the reading is >>>> as near to full scale as possible. That means a 5W HF >>>> element (is that >>>> even available?) would be ideal provided no more than >> 5W >>>> is put through >>>> the meter. A 10W element would be less accurate but >>>> provide a safety >>>> margin for the meter. Even better would be to have >> both >>>> elements and >>>> use the 10W one to get in the ballpark and the 5W one >> for >>>> a final check. >>>> >>>> 73, de Nate N0NB>> >>>> >>>> -- >>>> >>>> "The optimist proclaims that we live in the best of >> all >>>> possible worlds. The pessimist fears this is true." >>>> >>>> Ham radio, Linux, bikes, and more: http://www.n0nb.us >>>> >> >> > ______________________________________________________________ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:[email protected] >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: >> http://www.qsl.net/donate.html > --------------------------------------------------------------------- > Web mail provided by NuNet, Inc. The Premier National provider. > http://www.nni.com/ > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
