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Hello Jon, As you wish to use the antenna on the higher harmonics as well as 2M, I would suggest you use ferrites to create a Common Mode Choke (CMC) as noted by Roger. I suspect (but do not know, I

Yes,a dipole will work without a balun. But it is not a dipole anymore. The outer surface of your coax shield becomes part of the antenna system. This can give inaccurate results with the VNA. In

Your first link redirects to the same url the OP posted but I got to ask: What is your issue with the paper being hosted in Bosnia&Hertzegovina, the paper originated there. [email protected]>

I suspected the 50 Ohm calibration resistor and ordered two new ones. After recalibration and measurement, the SWR is 1.26 at 172 MHz and 1.65 at 522 MHz. Both measurements with SOL calibrated

Other sources that are in other countries than Bosnia Hertzegovina https://doi.org/10.7251/ELS1418029S https://doaj.org/article/f97e342395e443358e02546e68ea0fb9 The authors have a number of other

The SWR for a 50 Ohm cable will depend on the feedpoint impedance at the end of the cable. The impedance will depend on the antenna dimensions, its height, and its proximity to the environment. If the

You need to calibrate your coax SOL at the far end, so your readings look like your antenna is at the vna and not some distance away.9 [email protected]> wrote:

Maynard and others: You and we were most fortunate to be initiated with one of the most robust sunspot cycles of modern times in 1957!! Same story at pre-Nano VNA KN1CJO in southern Maine. Worked

I got my Novice license in 1957 and used a single wire routed out the window and up to the brick chimney and then across the yard about 100 feet to a pole. It worked fine, with my best DX using a

Nice find!

I ran into a research paper on measuring capacitors using a VNA that might be of interest. It analyzes capacitance and ESR accuracy for the S11 reflection, S21 series-through, and S21 shunt-through

Have you turned on the VNA's Smith chart? At what frequencies thru your sweep does the trace cross the chart's center (no reactance) line? Those are your antenna's resonant frequencies. The one

Joe, I got licensed a decade after you and did not have a chance to use a balun or 50 ohms coax then. My 40 and 80m dipoles were fed by 75 ohms TV cable. I did not have an SWR meter either. Still I

Yup! The Balun Craze is a new Generation thing. Got licensed in 1975, Never ever heard of a Balun. All my dipoles were direct feed. Only till recently has the myth of a dipole without a balun will not

It's measuring the 3rd harmonic which shows a nice low SWR. how far below 172 Mhz did you start your scan? Joe WB9SBD

I have never seen a problem feeding a dipole directly with an unbalanced feedline. The last dipoles I had up (which were for 40 and 30 meters) were just fed by connecting the two leads of the coax

Bob, Would you suggest a voltage balun or current balun at antenna feedpoint? One ham told me that if you use a voltage balun, it can bring down the high noise I have on 80m. Regarding the original

Hello Hobride, Unfortunately you have not supplied a photo of your test setup. A dipole is balanced at the feedpoint, your VNA is unbalanced. I suspect your problem is that you do not have a balun or

You did not indicate the range of your sweep. Try setting the sweep range to 150MHz to 190MHz, recalibrate open/short/load, then measure. I suspect that you will find the lowest VSWR near 171MHz,

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