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Hi Ron If it is the SWR indication build into your radio you are referring to, and your radio has an internal antenna tuner (or I would rather call it a impedance matching network), then the radio is

These figures for the impedance of CH0, CH1 will vary considerably with frequency. Jerry

What are you using to measure VSWR while transmitting. If you use a meter that simply changes scales with no re-normalization for any specific power, they are quite prone to read improperly when less

It's a shame they all appear to be 12V ;)

Thanks Larry. I'll try and find a "quality" one.

Thanks for the additional explanation, Herb. Sorry if I was too unclear. It would perhaps be possible for the software to have an 'auto' mode that started at a low frequency and increased it until the

Rune, I find myself quite often having to use an external graphics program to add descriptive text to the NanoVNA-Saver chart images I save (See attachment). Is it feasible to add a comment or title

On Fri, Nov 15, 2019 at 05:36 AM, Barry Jackson wrote: "If a particular frequency span setting, sweep mode etc. is needed for TDR measurements, should not the software set those modes temporarily when

This is my first post after lurking since October, so I'm quite new to the Nanovna. The Nanovna measurements of SWR are considerably lower than what I'm seeing when I transmit on-the-air. What does

Hello Rune, thank you for investing in the development of this measurement aplication very very close to the professional. I draw your attention to the TDR function or indeed the length marker is

Hello again, Thank you for the replies, and thank you Larry particularly. That was just what I needed. Well, I am not going to claim every single one of the 7000, because some are repetitive, and I

In post 1257: /g/nanovna-users/topic/32993803#1257 I calculated the output impedance of CH0 to be 51.53 ohms and the input impedance of CH1 to be 53.85 ohms. In the previous post of

That's probably a safe way to go, but the -H schematic is still showing the SD103AWS schottky while the STM32F072CBT6 datasheet has 4.0 max for the VBAT pin... not a lot of margin there.

Hi Herb I have done a lot of such measurements in the past and eliminated the inductance of the wire thru the core. In your setup I think you get even better result by doing a SOL calibration at the

The TDR range depends on the frequency step and hence the span. Use lower frequencies to measure long lengths and higher frequencies to measure short lengths. The software doesn't know in advance what

Hi Rune, Thanks for the new version which is performing well. One issue that puzzles me is regarding TDR. This seems to depend on other settings like frequency span, but I have not yet discovered in

The design of the Nanovna indicates the use of a standard silicon diode - not Schottky? as a number of members suggest. The reason for this, is to prevent the input to the uP from going above 3.9V,

A Schottky would be best but any regular (non-zener) would work. The footprint is SOD323 but most people use a PTH style. NSR0530HT1G (SMT) or SB530 (PTH) for instance.

Hi Tony, Welcome to the group.? You read all 7000 posts?!? :-) The NanoVNA is capable of displaying 1:1 SWR graphically so I'm not sure what you are referring to. You can change the scale on the

Hello Tony, You can adjust the scale of the swr graph. Display: scale: scale/div. 73 de Ton PA0ARR