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Hi Roger I do not use enhanced response, indeed i dont use an unknownen function for me, i use SeeSi H4 SM NanoVNA + DiSlord 1.2.40 Firmware , Serial resistor with reasonnable 2cm legs only for 30Mhz

Hi folks, I'm brand new here. I just got the NanoVNA-F V3 which is made by SysJoint. Like with my other VNAs (a cheap small NanoVNA-H & a LiteVNA 64) the first thing I looked for was the (custom)

I nearly fell out of my chair when I saw the HP fixture prices. May I suggest using these: https://www.sv1afn.com/en/products/-22.html There is a lot of other goodies on his website, and I have found

Dave, Where did you find the very large alligator clip shown in the photos in the document? My usual sources aren't turning up anything big enough to bite a bnc connector. Just curious. Andy

Alligator clips are OK if you just want to get a rough idea of the impedance of the device you are measuring. The problem with them is you have an impedance discontinuity from the coax to the clips

Something wrong with your S11 plot. It should be much better than that. Here is a re-post of my previous plot. S11 is flat but is off by 3 to 4%. Note that S21 is much better estimate at low

Hi Roger Here my plots of S11 and S21 measurement of the 4.63Kohm leaded resistor at same time , same graphe , same scale they are dramatically differents , and I prefer the S21 obviosly . May be i am

An ideal test fixture would maintain a 50Ω impedance right to the device body. The Keysight high-frequency SMD fixtures come close to this ideal, the device interface center conductor is a disk,

Those leads account for about +j5 at 28 MHz. I'm giving the leads about 28 nH of inductance. The +j5 ohms is about 10 % of your measurement system impedance of 50 ± j 0 ohms. Dave - W?LEV

Nizar, The NanoVNA-H4 is only a one-way VNA so it does not calibrate for s22 and S12 and only does six point calibration. In order to get good S21 series measurements you need the source and load

Hello Dave, I agree with Luc. Everything I've read about Smith Charts says that ABOVE the horizontal (resistance) centerline is Inductive, and everything BELOW is capacitive. But I still have a lot to

I have used mine to measure the inductance of antenna load coils that I have made. I fabricated a test lead that is a coax that terminates in a pair of alligator clips. I clip the leads onto a panel

Hi Dave It's a leaded resistor with 2cm legs 73's Nizar

Were you using a leaded or SM resistor in these tests? A picture of the setup might be of value. Dave - W?LEV [email protected]> wrote: -- Dave - W?LEV

Hi Roger You are right, i tested a 4.63 K Ohm serial resitor S21 gives me 5.35 Khom +15.6% error but regular static value across the 30Mhz span , S11 shunt gives me a very irregular values across the

Stabilize the S22 port with a 6 dB or greater attenuator for starters and 90% of the problems. In addition any VNA has trouble measuring high impedances. For measuring CMRR of my common mode chokes

Nizar, The NanoVNA H4 has difficulty making accurate S21 measurements for several reasons that have been posted many times in this group. I suggest you try measuring a 5K and a 10 K resistor using

Thanks, Nizar. There is almost no difference between the two methods for Z (|Z|), a bit more for R and I. This suggests that the residual shunt capacitance in your test fixture is negligible. The S21

Hi Brian Here S1p and S2P attached 73's Nizar

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