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It is a very powerful and useful device despite its size and cost. I have used mine for many purposes including using the TDR function recently to troubleshoot a feed line/antenna problem of a local

I got my first Nano VNA yesterday, a friend who used to live 10 miles away, now lives 1000 miles away bought it for me along with jumpers and adapters. Today I set up "presets" for 80, 40, 20, and 2

QUOTE: You will do far better to connect the right most antenna and collapse it *** Because the other two antennas shown in the image will not work well if at all on 433 MHz. The extendable

Hi What Smith measurements given with the reference load, the short circuit and open terminaison ??? It can help to better understand what can be the issue 73s Nizar

Hi Donald, Thanks for that, it was pretty much what I was expecting, and ties in with what I am getting with my DG8SAQ VNA. I am also using a silver mica capacitor with about the same lead lengths.

Hi Stewart, Out of grins and giggles I took a 470 pF silver mica cap which actually measured 454pf using smart tweezers. I then just used a test jig with my NanoVNA which was a white plug in

Uhm, right. This is over my head... I was looking to find another impedance measurements for the said antenna, so I can check my measurements against. It looks to me unlikely to obtain such, so how

it depends ... what about a vertical 2x 5/8 wave ?? also with a loading coil at centre but with some gain over a quarterwave ... and cause its endfed it may be halfwave on 2m and 2x 5/8 on 70cm as

I get accurate results when measuring capacitors with my NanoVNA so I assume it is something with your setup or calibration. Without photos or screenshots we don't have much to work with here. Here

Hi Jeff, Yes, you are right about the strays of the test jig, and about the capacitor lead length. However, I am using the same test jig and capacitor that, although not perfect gives milli ohms

Hi Stewart Even at 7MHz it is unlikely that you will not be seeing some stray inductance and stray capacitance, so I am more surprised, at the 0 -j50 ohms. Unless your test jig is very good and the

Indeed 442 pF at 7.2 MHz, that's 0-j50 ohms No need for software to calculate that. Z=1/Cw where w=2*pi*F C in Farad F in Hz pi 3.14 If with your NanoVNA you read: 11 ohms -j49 ohms, it's probably

Hi, I am trying to get to grips why I am not getting the same Smith Chart results with my NanoVNA as I am with my DG8SAQ VNA. I have got to the stage of trying to make everything as simple as

Hit send too quick. The way these work is the bottom 1/4 wave has a high Z at the top. The coiled section moves that up, and ideally is a 1/2 or 1 wavelength that does not radiate, then you drive the

Not necessarily - depending on the lengths. What you might wind up with is essentially a colinear array, with either a dipole stacked over a monopole or dipole stacked over a dipole, and that coil in

Because the antenna that is center loaded with a coil will have less gain than a 1/4 wave marconi antenna.

I have fault tolerant outlets in kitchen and bathroom. Any time I key up on 70cm band within a few meters of those outlets, they trip! The 2M band doesn't do this... Matthew KD6KVH

"You'd be surprised how sensitive modern electronics are to stray RF fields!!" Not at all surprised. I recently had to remove the flatbed scanner from the desk where the computer it is connected to

Just simple overload of the sensors. They typically are tied together throughout a single installation which may consist of a whole apartment complex. If one is tripped, the whole complex is

Just want to understand correctly why the fire alarms went off. I'm thinking the fire alarms are on the 450MHz band somewhere. So are they set off due to some harmonic from the HF bands you all are