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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

Orrin 0.7.3 appears to be the latest, released last week https://github.com/NanoVNA-Saver/nanovna-saver/releases/tag/v0.7.3 Is working ok on both my win 10 and win 11 machines Good

Nah, not even remotely a possibility. One of the three machines is a server-class box that doesn't have a battery (other than the CMOS backup cell). Kind of got it down to changes in the kernel

VK2KKZ de WN1Z Phil, that's good news, a clone is unlikely. The 'RUNING' typo is also visible on the Sysjoint SV4401A io.groups announcement of 0.5.9 firmware. I posted over there that i found

Orrin This post mentions that "firmware of SV4401A is encrypted, we have not found a cloned SV4401A so far on the market" https://sysjoint.groups.io/g/main/topic/sv4401a_clones/104681340 Mine also

Why do you say that ? Can't find the extensible antenna anyway.

I would not say that. Aside from measuring a monopole + cable and not just a monopole, it is not only loaded but also 27 cm long (17 cm for 433 MHz). Probably in order to present a good match to the

None of these antennas are really any good at HF frequencies and certainly NOT down too 100 kHz. Sure, any hunk of conductor will capture "something". But only the one on the right is acceptable for

Sounds quite low. A monopole against a ground plane will be in the 25-35 ohm range. That one is obviously center loaded, but perhaps not for 433 MHz (more likely cell band at 850). Did you also get