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Then I'd go for "what's the mfr's test fixture/reference design look like" (if there is one..)

In my case, this will be a transmitter with the antenna driven by a MOSFET H-bridge with less than 1 Ohm source impedance and only a few inches of wire, so a low antenna impedance means more power can

I have 4" x 10" sheets of brass and aluminum I can hold up to the antenna and see the VNA plots move a bit, and steel moves them a bit more, but nothing on the scale of the difference between my plots

Indeed.. at 125 kHz and low power for embedded systems, 50 ohms matched circuits would be pretty unusual. Consider the AM radio in a car - not 50 ohms. At low frequencies (consider 60 kHz WWVB

Does the mfr provide a "how we measure it" document? Test fixturing, sample circuits, etc. are important. You'll see this kind of thing with devices designed for use in embedded systems - For

Hi Doug, having done quite a few RFID antennas, that 1 to 1 is rather optimistic. One thing to consider, do you have any other metal within a foot or so of the antenna?? ?You can easily see a pair

I have a 125 kHz RFID antenna consisting of a coil and series tuning capacitor. The manufacturer supplied plots of the SWR and Z of the antenna showing a nice 50 Ohm 1:1 SWR at resonance. I have tried

exactly !

Hey Dave, I agree with you, my TI99/4A is still my favorite. (just kidding but I did use it for years) I now use win 7 and buy malware to keep it clean. Mike C.

Your display looks OK but 462 ps would be the value for a very short transmission line - about 4.5 cm long. What is the length of your transmission line and what kind of coax is it? Here is a video

I would solder the coax shield to the area labeled GND in the antenna design, not to the ground plane nearby.

Hi Dianne, What model/version of the nanoVNA do you have? many do not cover the 2.4GHz bluetooth frequency band. What diameter/type of coaxial cable are you currently using? Type RG316 has diameter

Thanks for your reply. I managed to correct the delay I was asking the same question to my tutor about the size of the cable in relation to the PCB. I am on an internship and I have to design a PCB

Hello, Thank you for your answer. My DUT is a PCB trace antenna. Attached is a picture of the antenna. I need to perform the measurement in the feed line of the antenna. I am in an internship and the

Hello, Thanks for your response I've got -462ps for the delay correction is it good? Best regards. [email protected]> a écrit :

The most accurate way is to calibrate at the end of the cable using a short, open and a 50 ohm SMD or very small resistor with absolute minimum leads. The other way is to use the electrical delay to

What exactly do you want to measure? What is the Device Under test, DUT? Is it the PCB? Is it the cable? Is it the combination of the two? If you just want to measure the PCB you need to do the

You have to calibrate at the cable end with open short load And with such big cable soldered to such a tiny pcb your results will be at least questionable... On so high frequencies even an sma to n

I bought my NanoVNA in large part to have a solution looking for a problem to solve. My main use for this device was the SWR sweep capability for my antennas, but I soon discovered previously unknown

Theory is always incomplete. It is said that the field of thermodynamics learned much more from the operations of steam locomotives than steam locomotives learned from thermodynamics. Often electrical