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Thanks to DAve W0LEV and others for bring up the subject of error analysis and significant figures. My own background is like Dave’s; a physics degree in 1965. Our professor in senior labs was very

Dave, I don't normally post here (although I read everything via email). I just want to thank you for your very informative history of RFID. It's something I've worked with for a number of years but

I do not have a VNA. I rely on Rudy Severns, N6LF, for data. He recalibrated his VNA at the SMA connector, measured a short there, and now MA mode does not affect the file data. In addition, |S11| is

I am one of several engineers who worked for the company that originally introduced RFID to the world, AMTEK. They no longer exist as many start-ups go. The company was fresh off "The Hill", Los

Brian, As a reference point, when calibrated, the HP 8753D has a linear magnitude reflection uncertainty of 0.015 or so when the reflection magnitude is near 1. I am not sure if that means the

Settings: 401 points, 0.1-50 MHz, bandwidth 100 Hz, arithmetic 4X smoothing, power = 4 mA Brian

Measurement of a short at the VNA connector after clearing cal: 49002000 -0.869956992 0.080768176 49126750 -0.869913280 0.080994536 49251500 -0.869870784 0.081221216 49376250 -0.869828352 0.081447216

I'm sure that at least a few here are familiar with the following section from the STMicro application note "AN4974: Antenna matching for ST25R3911B/ST25R391x devices", since it calls for the use of a

That's "total power" or 1E-4 on I and 1E-4 on Q (so 1.4E-4 on absolute voltage)?

Jim, I can assure you our STEM students know nothing about significant figures! Terry (Dr. Terry Bullett) and I have tried, but no knowledge of the concept. They are Juniors going into their senior

On 4k IFBW as i can see H4 measure error (due to noise) on 100-200MHz near ~1e-4 (on linear trace) On 100Hz IFBW, near 1e-5

On 6/14/22 9:24 AM, W0LEV wrote: > Thank you, Jim!!! > > Again, we are not running a metrology lab nor do our measurements approach > those of HP, R&S, Tek, and others. Something my PhD friends tell

Thank you, Jim!!! Again, we are not running a metrology lab nor do our measurements approach those of HP, R&S, Tek, and others. Something my PhD friends tell me is that error analysis and assignment

Thanks for the reply, DiSlord. I'll check with Rudy, but I believe he calibrated at the VNA SMA immediately before the measurement since normally he never measures without a cable.. Brian

what would be interesting is to measure it without calibration, and with, and make sure there's not some mis calibration going on somehow.

I've asked Rudy to remeasure the short and open using MA (magnitude/angle) mode. That might shed some light on where the inaccuracy lies. Also, I think he was using averaging. It might be interesting

I think need recalibrate. Calibration must remove all errors.

Interesting - I wonder if it's a "round off" or truncation error of some sort.? The "detector" mixes with I/Q 5 kHz, summing, and there could

Carsten, my experience is all antennas, even those off the shelf one, need some finetuning. 1. Tuning - I would recommend the minimal height for tuning purposes is 3-4m over the ground at the end of

I tried this just last week. It seems work like a spectrum analyzer but having doubts about calibration. For this purpose I used Satsagen software and my HackRF One. -- ALVARO, EA8ARX