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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

The VF for the TDR test will be the same no matter what length you cut the CAT6 cable. VF for a specific type of cable will vary by manufacturer and even different between production runs by the same

For some reason, my messages are not making it to the email chain...they are in the groups.io online...

OK, I see what you mean, and I suspect the the VF can vary by 1% over the length of the cable. I will test with a piece of CAT6 by cutting one wire and reconnecting at one foot intervals.

The resolution is 4.8 mm but the accuracy will be worse because you cannot enter the VF to more than two digits. So if the VF is 69.5 % and you have to enter 69 or 70% that will affect the calculation

Sigi, Yes, I have a piece of CAT6 cable to test. I removed the jacket at 1 foot intervals for about an inch. I will test by cutting 1 wire at a time at each location and see what I measure. Geoff

take 10 inch of speaker wire.. that should show almost similar numbers.. if thats the case then yes you can trust it dg9bfc sigi Am 23.08.2023 um 22:52 schrieb Geoff Peters - AB6BT: