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]
