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Hi betex, I would like to share also to you my test results when I tried to make a 1/4 wavelength ground plane antenna at 1.2GHz to test the frequency performance limits of nanoVNA. The graph result

Mine doesn't seem too bad, better than most that I have seen. But I think it's luck of the draw what you get supplied with. I have done a LOT of business with 409shop in HK (excellent dealer !!!), and

This is an effect of common mode current on the outer side of braid. The outer surface of the coax cable become a part of antenna. And when you connect usb cable it also become a part of antenna,

For S21, the good choice for output attenuator is equal to amplifier gain. And for input attenuator the good value is 20-30 dB attenuator. For example, if your amplifier has 40 dB gain, then use 20 dB

For S11 you can connect CH0 to input and dummy load on the amplifier output. For S21 you can use 20-30 dB attenuator on the input and 20-30 dB attenuator on the output of amplifier. You can calibrate

The first part of that statement is correct, but the last part isn't. It's not coupling from the balanced dipole to the coax that causes shield currents ... it's the simple fact that the antenna is

Me strange, nooo. ;) The RG316DS over the years I've likely used more than 2000ft of it. Most are two braids but it tends to be more phase stable than single braid. If you need critical phase

PVRC member AA3S Doug Hart gave a presentation on the NanoVNA that is a good intro to some of its measurement capabilities. His TDR example, showing the impedance change from 50 ohm to 93 ohm cable

As previously posted, you will need to add a suitable 50 ohm pad to both CH0 and CH1 and do a full calibration with the pads in place. Hence, you must take care not to drive the DUT into compression

Hi Allison, I have been using RG-316 with SMA for years. I also try to avoid RG-174, even though I have a HUGE spool of it made by Alpha, Just this week, I found some Belden RG-174DS (double shield)

This thread has been locked. It is not adding to the technical knowledge or expertise about nanovnas. DaveD

Greetings Betex, What you have there, in the first picture, is not a ground plane; it's a patch antenna closely coupled to a rod antenna. This is causing a severe imbalance in coax currents, causing

Nice arrangement.? Thanks for the updates On Sat, 30 Nov 2019 at 12:23 PM, Gyula Molnar<gyula.ha3hz@...> wrote: Latest firmwares I've found a picture of. 73, Gyula

Andy, If the input circuit is overloaded the errors multiply and the reflected impedance is not correct. My UV5r measured using a HP4191A at -30dbm gives far more reasonable reading inside the 1.5:1

This is a tricky case as the power out can overload the device. The solution I use is attenuate the output, run S21 and use an external return loss bridge with an amplifier on the return port to the

I use minicircutis series cables as they were purchased for a project where I used higher end VNAs. so the case is nice 1M cables gets used. I also make cable for use and have a set of 30cm RG316

I am using a cell designed for digital cameras ans is 1200mah and accepts the 1C charge safely. I prefer to keep the charge rate at .4C, charge time is not an issue as I have three of them and a

W5DXP, Not a windows user but I've heard that is the case. A handy thing. With the above in mind I had a moment where I considered porting Nanosaver to QB45 in a moment of pure madness. I can run

Hi dna.dana@... - You are probably a recent subscriber and likely frustrated by documentation provided with your nanoVNA, which may be better or worse but probably different from that provided for

Hi Allison, just a small correction: Python 2.7 is 9 years old, and at the time of release was described as "the last major version in the 2.x series". The author of Python requested that developers