¿ªÔÆÌåÓýThis is a real interesting thread. So I thought I¡¯d throw in my two centsA SA is not a power meter..... ?actually it is and in some respects a better one. ?True you do have the issues of calibration but assuming you are calibrated you should be able to get within a couple of tenths of a dB. Where the SA shines over a power Peter is that you are measuring the power at your frequency of interest not the fundamental and all of its harmonics like a PM or a bird does. Calibration, ?well I have had to do inspections (why they let me do QA inspections is beyond me) and I have found exactly two labs that could actually put stickers on power heads with a straight face one was HP Roseville (a while back) where they had the 4 or 5 racks of stuff for PMs and Heads. The other was of all places the Pakistani Navy lab in Karachi. They had HPs desktop sets for both PMs and heads. ?Everyone else used a sig gen to verify the heads and none of them did the entire frequency range nor the math to generate the Cf. ? I¡¯m lucky I have the 11683 range calibrator and a Keysight lab stds calibrated 3458A so I can be fairly certain that my power meters are correct, operative word ¡°fairly¡±.? Over the last year or so I have had over a dozen 436As up from one of my customers because they ¡°wouldn¡¯t cal¡± or were BER, they all got sent back working because I actually read the manual and performed the alignment (with the 11683). ? The bottom line unless you really know your lab and even then that they actually do alignments everything we have is a guess, maybe a good guess, but still just a guess.? Remember in radio it takes 6dB ?for you or me to detect a change in the signal. ?Of course if you¡¯re doing it as a challenge that¡¯s another thing. Regards, ? Stephen Hanselman Datagate Systems, LLC On Oct 7, 2020, at 10:59, Robin Szemeti <robin@...> wrote:
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