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Although the ARRL Handbook states, without qualification, that the shunt element always goes on the high-Z side (2021 Handbook, the latest I have), that is strictly true only when the impedances to be

If I may ask a follow up questionsabout Nano VNA-H. 1. Is port CH0 input a 50 ohm resistor load? 2. If #1 is correct, would proper attenuator implementation for the port be a series resistor, to form

The last FW is the 1.2.24 the last DisLord app version is 1.1.215 now. This last FWs for H and for the H4 also included the exe file,

You probably flashed the wrong firmware variant, you used H version instead of H4 version.

A couple of things to consider: - When you say "measure the impedance of the antenna" in this case you are really measuring the impedance at the end of the coax feedline. It will be much different at

Also, know that with L-Networks, the shunt element goes on the high-Z side. Dave - W?LEV -- Dave - W?LEV

Hi Andrew. You can also apply a formula, use a pencil and paper and a calculator and obtain a simple match that will accomplish most Z matches to an antenna. If you have a representative frequency,

SimSmith includes various matching topologies as part of the Smith Chart presentation: http://www.ae6ty.com/ Dave - W?LEV wrote: -- *Dave

Hi Andrew For me, SimSmith/SimNEC is the right software to do those calculations. Very helpfull. 73 - Antonio EA7HJ

Hello, Having read through the Group, I've not been able to find an answer to my question, but I have found a lot of information that suggests several members of the Group will know ... here's the

I recently purchased a NanoVna H4 and found that it had the 1.2.14 firmware. I followed the procedure for downloading the DFU uploading application, then downloaded the firmware. I connected the

Thanks, Jim. As you have likely gathered by now from my (too many) posts, in retirement I'm into promoting the hard sciences and math to the HS bunch and helping others learn the finer points of all

The universities *are* buying these by the dozen. Prof Ashwin Iyer at University of Alberta used them in a "intro class" along with a VOM (ECE 478) a bunch of parts and modules, etc. Even a soldering

Excellent work, Barry. I've always contended introduction of the NANOVNAs would be an outstanding tool for learning. You've proved that. The universities ought to be buying these in the 100s to teach

Donald, I'm not sure I can get the resolution necessary from the "far" end. The cable is 100m long and the fault is about 240mm from the "near" end. Geoff

What I found reassuring is that the four graphs (on all three antennas) all agree with each other! The RETURN LOSS (dB) is sharp (yes, I plot it as a negative value) showing the reflections are least

Bob, Thanks for that. Yes, I have measured the skew, because of the twists per inch (pitch?) the tighter the twist the longer the wire physical length as well. I read that a maximum of 50nS/100 meters

Hi Geoff, You probably already know this, but each pair in a Cat6 cable has a different "twist rate" to minimise crosstalk, so the VF for each pair will be slightly different. Try it with a piece of

Right, yes, I know the VF is independent of length. The test has nothing to do with determining VF. I have already done that with a piece of known physical length. The test I have set up is a piece of

Measure from the other end and see if the two results add up to the correct total length. If they do you can at least have better confidence. If they doi not you know there is a problem. 73, Don N2VGU