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Allison, My previous comment to WB2UAQ was not about testing the 49:1 UN-UN wuth S21. It was about measuring the high feedpoint impedance of his 67 ft wire at 7 MHz. For high impedances like this

Larry I just watched your video and it does a good job of explaining the three methods. If you are interested in doing a follow-on it would be interesting to see the following: 1. Comparison between

Larry, Impedance measurement is more indirect then measuring the transformer directly. Both get you to the same point but the big thing is you have to understand what your measuring and what that

Roger, S21 to get it right really requires a known transformer or often easier two of the same back to back. That keep measurement in the 50 ohm domain and also allows for reasonable accuracy for loss

Hi Rune, I want to tell you that I have added two parts to my NanoVNA tutorial: a) Part 2: the NanoVNA-H up to 1500 (1300) MHz with examples b) Part 3: the NanoVNA als TDR (= Time Domain

I recently made a video showing how to measure impedance 3 ways with a VNA including the s11, series sw1, and the shunt s21 methods. See https://www.youtube.com/watch?v=1UbEz73FGCU if interested.

Yes, the current brightness interface is very primitive. I need to provide a more friendly operation. Thank you for your suggestions.

The NanoVNA originally designed by edy555 allows the use of DAC to adjust VCTCXO, but when I made NanoVNA-H, I thought that adjusting VCTCXO was too much trouble for most users, so I used TCXO. For

On Sat, Mar 14, 2020 at 09:38 PM, <hugen@...> wrote: The NanoVNA-H4 uses DAC output dimming, so the brightness can be adjusted using DAC commands. Dac_value = 800 is the minimum brightness,

Thank you for the command information, Hugen. I have a minor H4 firmware enhancement request: is it possible to use the jog switch to change also brightness when in the brightness config GUI menu? I'm

hwalker11 is right. The NanoVNA-H4 uses DAC output dimming, so the brightness can be adjusted using DAC commands. Dac_value = 800 is the minimum brightness, dac_value = 3300 is the maximum brightness,

On Sat, Mar 14, 2020 at 07:10 PM, Larry Rothman wrote: Maybe Hugen can let everyone know if there is a Console command to adjust the brightness on the H4?

Kurt, Thanks for your comments. Yes I am familiar with the using Rp instead of Rs in NanoVNA saver. I agree that the CH0 and CH1 impedance needs to be close to 50 ohms for accurate results using the

Maybe Hugen can let everyone know if there is a Console command to adjust the brightness on the H4? I've been attempting to keep Cho45's Original userguide up to date and have added quite a bit of

Thank you, found that out later after I did the jumper update. I'm just scared to mess with the display setting anymore I don't want to end up stuck with a dark screen. It may be as bright as it gets

Robert, You no longer have to open the case to jumper the booth pins.? To put the unit into dfu mode, turn it off, press in and hold the jog switch and then turn on the unit and release the switch.?

Hi Roger Using the S21 methods requires that both the source (CH0) and load (CH1) impedance are pure 50 ohm, so you get also errors this way. Have you tried to read the Rp instead of Rs in

Yes the S11 bridge method starts to get quite inaccurate after the impedance gets higher than a few hundred ohms. Fortunately the NanoVNA can do S21 measurements and we can determine complex impedance

I have tested the 1:49 transformer loss and found it to be 1 to 1.5 dB depending on the band. I checked this loss several ways with good agreement using the Nanovna. I also measured the feed point

What are the exact steps to adjust the display brightness? Mine comes up with a keypad and 1 800 I think it was. I tried something and it went dim and I managed to get it back where it was. I would