Because accuracy is or isn't. 73,
HNY Gary KA1J > Just wondering. Why is an accuracy within less than 1dB important? > > Happy New Year. > > 73, > > Bob Nobis - N7RJN > [email protected] > > > > On Dec 31, 2015, at 09:42, Ed Lambert <[email protected]> wrote: > > > > John, > > > > Thank you for your response. > > My original K3s test setup was per the manual: good quality dummy load (not > > the DL1 because of its 20 watt upper limit) with the ATU off. My high > > quality dummy load does not have a test point. > > After reading your results, I decided to take the DL1 as my "truth model". I > > found that the W1 display was 0.8 dB high and the K3s power display was 0.9 > > dB low. Each one was at the opposite end of the error budget. (sort of like > > winning the "losers" lottery). > > So, I set up the W1 to match the DL1 up to 20 watts and, surprise, the W1 TP > > voltage is now 4.87 volts. > > I don't have the W1 software and cabling installed yet. At that time I can > > fine tune all of this. > > It seems as though a consensus is building that the W1 manual specification > > of 4.5 volts is no longer correct, unless there is something "off" with the > > W1 internal algorithm. > > Good stuff. Thank you everyone for your comments and help. > > > > -----Original Message----- > > From: Elecraft [mailto:[email protected]] On Behalf Of John > > Oppenheimer > > Sent: Thursday, December 31, 2015 7:22 AM > > To: [email protected] > > Subject: Re: [Elecraft] W1 > > > > Hi Ed. > > > > The W1 DC voltage calibration resulted with incorrect reading with my W1. My > > hunch is that components have changed since Elecraft established the TP1 DC > > calibration voltage almost a decade ago. > > > > I have a KX3F with unchanged factory power calibration. Based on comments > > from Wayne, the KX3 is calibrated at 7.0 watts. > > > > My W1 TP1 voltage is 4.812 using a Fluke 87V > > > > Setting up a test bench with KX3 -> W1 -> DL1 > > > > Using W1 Utility to display W1 power: > > http://www.elecraft.com/software/W1/elecraft_w1_software.htm > > > > TP1 V = 4.812 > > KX3 power = 7.0 W > > W1 power = 7.02 > > DL1 V = 12.91 = 6.93 watts > > > > The W1 20 dB directional coupler does absorb power, at 7 watts, the > > directional coupler will absorb 0.07 watts. Adding 0.07 to the DL1 > > measurements equals 7.00 watts. > > > > John KN5L > > ______________________________________________________________ > > 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 Message > > delivered to [email protected] > > > > ______________________________________________________________ > > 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 > > Message delivered to [email protected] > > > > ______________________________________________________________ > 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 > Message delivered to [email protected] > ______________________________________________________________ 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 Message delivered to [email protected]
