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Re: NanoVNA-App in app calibration problem (bug?)
#calibration
#nanovna-app
Follow-up to last post. Here are some more measurements of a 1K SMD DUT. Using NanoVNA -H4 (1.2.19 fw) in standalone mode (no PC) and comparing it to NanoVNA Saver and OD NanoVNA app. Measurements made on H4 were exported as a s1p file and imported into NanoVNA app for plotting.
1. Compare NanoVNA-H4 and NanoVNA Saver using 3M coax cable. 2. Compare NanoVNA-H4 and NanoVNA App using 3M coax cable. 3. Compare NanoVNA-H4 using 3M and 15 cm coax cables. What is evident is close agreement between the 15 cm and 3M results when using the NanoVNA-H4 in standalone mode. So the long cable de-embedding works nicely on the -H4 firmware by DiSlord. Comparison between Saver and -H4 in standalone mode with 3m coax also showed good results. However NanoVNA app does not do well on 3m tests. Roger |
Re: Can't recall saved calibrations from SD card.
#calibration
#firmware
#nanovna-h4
Thanks for the reply and information.
I did recalibrate and saved them to SD. But the RECALL FROM SD menu item isn't there in 1.2.14. I rolled back to 1.2.0 for now. Regards |
Re: NanoVNA-App in app calibration problem (bug?)
#calibration
#nanovna-app
On Wed, Mar 1, 2023 at 10:05 PM, DiSlord wrote:
I agree that you should calibrate for the measured range and that interpolation must be used carefully. Here are two examples where I calibrate over 50k to 900 MHz and want to measure some 0805 SMD resistors. I am not using interpolation. Test conditions: --------------------- - NanoVNA-H4 was calibrated for 50 to 900 kHz. but measurements were made using OD NanoVNA app and NanoVNA Saver version 5.3 - Calibration in both programs was done using 401 points and without sweep averaging - 3m of RG-316 coax was used with SMD test jig on far end. Calibration load was 50 ohm 0805 SMD resistor (see attached for photo of setup). Two 0805 SMD resistors were tested (100 and 1k ohms) - NanoVNA Saver test results saved as s1p file and imported into NanoVNA app for plotting comparison. Results are attached. It is easy to see that something is wrong with NanoVNA App calibration on longer cables. Roger |
Re: Driver for nanVNA
Hi david
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I am not at home right now so not near my laptop but this might help? On 2 Mar 2023, at 4:44 pm, David Reams <dwr.kj4de@...> wrote: |
Re: NanoVNA-App in app calibration problem (bug?)
#calibration
#nanovna-app
I agree. A tiny bias above 1 along with noise. I plotted it just to compare with the earlier NanoVNA-App plot.
Brian |
Re: NanoVNA-App in app calibration problem (bug?)
#calibration
#nanovna-app
@Brian - It may be relevant. Comparison of Open in calibrated NanoVNA-App and calibrated NanoVNA-Saver. In Saver it looks better, oscillating around 1 and in NanoVNA-App it is > 1 for all points.
|
Re: NanoVNA-App in app calibration problem (bug?)
#calibration
#nanovna-app
On Thu, Mar 2, 2023 at 07:52 AM, <btomek@...> wrote:
It's not due to noise. The data is noisy, but the real part is > 1 for all points. I have seen this in other VNAs. I don't think it's pertinent to your calibration issue. Brian |
Re: Driver for nanVNA
It looks like it is conflicting with another port. Below is what I am
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seeing on my laptop: [image: image.png] [image: image.png] It appears that it is trying to conflict with Port 3. What is the best way to solve the port contradiction? Again, thanks for your help!!! David On Wed, Mar 1, 2023 at 4:36?AM robert miles <bob@...> wrote:
Hi David |
Re: NanoVNA-App in app calibration problem (bug?)
#calibration
#nanovna-app
On Thu, Mar 2, 2023 at 07:05 AM, DiSlord wrote:
@DiSlord - But that's exactly right. The measurement range is identical to the calibration range, the number of points is also the same, the calibration frequencies are equal to the measurement frequencies, and the result in NanoVNA-App is incorrect. Note that your "GOOD" files also have invalid |S11| values.@Brian - For OPEN and SHORT calibrators, such values are correct because ideal OPEN = {1.0000000 0.0000000i} SHORT = {-1.0000000 0.0000000i} Adding the measurement noise and interference, we can get |Sij|>1 Another little error may have been added by a malfunctioning calibration in the NanoVNA-App. |
Re: Can't recall saved calibrations from SD card.
#calibration
#firmware
#nanovna-h4
Remember state - allow save some device settings after power off like:
Start/stop frequency Bandwidth Backlight Options Threshold - this option set frequency threshold after this device use harmonic mode for measure Old calibration not possible load on new firmware, need recalibrate and save new |
Can't recall saved calibrations from SD card.
#calibration
#firmware
#nanovna-h4
Hi there, I¡¯m running Hugen¡¯s 1.2.14 firmware, which I like because it lets you save more calibrations. It will also do more data points across the sweep.
But I lost some of the defaults along the way, so I have some questions. What Expert settings do people use for stuff like Electrical Delay and Threshold? And what does REMEMBER STATE do? Lastly, I can save my calibrations to the SD card, but can¡¯t find a way to recall them from it! Any guidance gratefully accepted. Thanks |
Re: NanoVNA-App in app calibration problem (bug?)
#calibration
#nanovna-app
Calibrate device in measured range.
Interpolation not give good results for long cables (on big phase change for measured points) |
Re: NanoVNA-App in app calibration problem (bug?)
#calibration
#nanovna-app
Hello Roger,
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Just an observation, The green App curves have a distinct spike at the 5351 clock gen harmonic change points; ~300MHz, ~600MHz, 900Mhz. Cheers...Bob VK2ZRE On 2/03/2023 5:20 am, Roger Need via groups.io wrote:
I did a comparison calibration with the NanoVNA itself and NanoVNA app (DiSlord version) using a cable that was 30 cm (12") long. Results were better than the 3M cable I posted earlier but I think I will stick with NanoVNA calibration and no longer calibrate in NanoVNA app. |
Re: check "Dollar Tree" store. Now Dollar and a Quarter!
Dave,
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Totally transparent now. 73 John VE7KKQ On Wed, Mar 1, 2023 at 11:24?AM Dave Merrill <r390a.urr@...> wrote:
The outlets my SIL replaced came from a reputable source, NOT Dollar Tree. |
Re: reinforce cables with a bit of glue
On Wednesday 01 March 2023 02:16:03 pm KENT BRITAIN wrote:
The only time I have had any issues with a USB cable was with a girlfriend.?? She would jerk the plug out of the phone pulling on the cable rather than grabbing the connector.I know of one young lady who used to do that with extension cords, until the time she did it and the cord came away, leaving the plug in the socket and enough wire sticking out to generate quite the light show. I don't think she did it again after that.. :-) -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin |
Re: check "Dollar Tree" store. Now Dollar and a Quarter!
The outlets my SIL replaced came from a reputable source, NOT Dollar Tree.
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Sorry if that wasn't clear. Dave N9ZC On Wed, Mar 1, 2023, 12:38 PM John <ve3kkqve3kkq@...> wrote:
I would NOT use wall outlets, light switches or anything else that |
Re: reinforce cables with a bit of glue
They have an inventory of about 50 different USB cables of different types, colors, and lengths.Pick the one you think looks best.?? The only time I have had any issues with a USB cable was with a girlfriend.?? She would jerk the plug out of the phone pulling on the cable rather than grabbing the connector.
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There are NO companies in North American making USB cables and power supplies.They are all coming from the same Foxcon plants in the PRC.?? Yes, Apple charges 10 times more for the same accessory that came out of the same plant. Personal mods to equipment and accessories is the hallmark of hobbiest like us. Gee .... after all, where did the Nano's come from! hihi On Wednesday, March 1, 2023 at 01:04:22 PM CST, Charles Young <ctyoung@...> wrote:
If the Dollar Tree cables look weak you might reinforce the back end of the connector-cable connection with a bit of super glue or epoxy. Chuck KF8TI |
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