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Nanovna-F is here
Oh...... my....... GOODNESS!!!
I love Nanovna original. I have three of them. But Nanovna-F just arrived and it is simply fantastic. It is heavy, thick, completely encased in aluminum and it has a huge, gorgeous 4.3 inch screen that I can see easily without reading glasses. It feels like comparing an S Class Benz to a Prius. Both are fantastic vehicles but...... well..... who would take the Prius. Easily a 50 dB dynamic range at 1 GHz. Comparison tests to come but I can already tell it is at least the equal of the little brother. Did I mention the screen? Just wonderful and I got it for $116. WA8TOD |
Re: SOLT calibration vs. TRL
True, however, I was thinking forward as I understand a 3 channel nano receiver is under development. Further, the technique for obtaining true 2 port s data currently requires unbolting the test device and turning it end for end. Not sure the calibration in that process would hold up. Thoughts? Unless a simple after market S parameter test set is developed.
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Re: SOLT calibration vs. TRL
Dr. David Kirkby from Kirkby Microwave Ltd
On Tue, 15 Oct 2019 at 20:28, Dr. David Kirkby <
drkirkby@...> wrote: What I meant to say is that when using TRL* calibration on an HP 8753, 6 to 10 dB attenuators need to be added to the test ports of 8753 VNAs. The 8720D instrument I have, was available with an optional 4th receiver to allow full TRL calibration. It was option 400 and quite expensive. My instrument doesn¡¯t have that capability. Also a full S-parameter test set is needed. I don¡¯t believe that TRL, or any similar calibration procedure, will be possible with a simple VNA. Dave -- Dr. David Kirkby, Kirkby Microwave Ltd, drkirkby@... Telephone 01621-680100./ +44 1621 680100 Registered in England & Wales, company number 08914892. Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Chelmsford, Essex, CM3 6DT, United Kingdom |
Re: SOLT calibration vs. TRL
Dr. David Kirkby from Kirkby Microwave Ltd
On Tue, 15 Oct 2019 at 19:11, alan victor <avictor73@...> wrote:
The group has been focused on SOLT or so called SOLM (match) for TRL calibration requires a VNA with 4 receivers. The HP 8753 series, which have 3 receivers, can perform something HP refer to as TRL*. This requires a good match at the test ports - typically 6 to 10 dB on each test port. It is not as good, but it is not possible to do true TRL calibration on a simple VNA. I don¡¯t think anything other than SOLT is likely to be practical on the NanoVNA. Actually, waveguide calibration is possible too, but waveguide is not very useful under 1.5 GHz. Dave -- Dr. David Kirkby, Kirkby Microwave Ltd, drkirkby@... Telephone 01621-680100./ +44 1621 680100 Registered in England & Wales, company number 08914892. Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Chelmsford, Essex, CM3 6DT, United Kingdom |
Re: A simple, and reasonably accurate way of simply entering the properties of WELL ENGINEERED calibration kits.
Dr. David Kirkby from Kirkby Microwave Ltd
On Tue, 15 Oct 2019 at 19:51, Jeff Anderson <jca1955@...> wrote:
Some of us have commercial cal kits for which C0 (as well as C1-C3) and The best way to do this is to perform a calibration then measure the properties of a very good transmission line shorted at the end. The amplitude should be constant with frequency. Errors will cause a ripple But that requires good calibration standards, in addition to However, for initial testing of software, that is unnecessary. If one performs two calibrations 1) A delay of 40 ps and a fringe capacitance of 30 fF 2) A different (longer) delay and a fringe capacitance of zero should give very similar results if the longer delay is suitably chosen. There is a mathematical relationship between a small change in capacitance and offset length. So no hardware is needed. Dave. --Dr. David Kirkby, Kirkby Microwave Ltd, drkirkby@... Telephone 01621-680100./ +44 1621 680100 Registered in England & Wales, company number 08914892. Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Chelmsford, Essex, CM3 6DT, United Kingdom |
Re: A simple, and reasonably accurate way of simply entering the properties of WELL ENGINEERED calibration kits.
Dr. David Kirkby from Kirkby Microwave Ltd
On Tue, 15 Oct 2019 at 18:06, QRP RX <qrp.ddc@...> wrote:
On Tue, Oct 15, 2019 at 07:50 PM, Dr. David Kirkby from Kirkby Microwave Unfortunately setting the delay after calibration with DISPLAY - SCALE - ELECTRICAL DELAY menu. will not give good results for many connectors - in particular for N connectors. The reason is because that only changes the phase, which is what happens if you move along the transmission line. Unless * A delay of the short calibration standard * A delay of the open calibration standard * A capacitance of the open calibration standard (as a minimum C0). are all set up *before* the calibration commences, the calibration will not be good. There will be both amplitude and phase errors. Those errors can not be corrected by just changing a delay. The lack of delays doesn¡¯t present a problem with female SMA connectors, as the delay of the male short and male open are very close to zero. But it will cause problems for most others connectors. The correct sequence of events should be 1) The user specifies the properties of the calibration standards (delays and capacitance) 2) The calibration standards are measured by the VNA 3) The error terms are computed. 4) All measurements are corrected using the error terms. Would you be able to implement something that allows the user to save a few calibration kits? Four should be enough for anyone. It would be good if the user could name the kits - eg, SMA, N, BNC, 7-16 etc, but if not simply CALKIT 1, CALKIT 2 etc would do. Note that the male and female connectors are generally different. It is normal nowadays to specify SHORT -M- to mean the male short calibration standard. I can find relevant equations. Dave. -- Dr. David Kirkby, Kirkby Microwave Ltd, drkirkby@... Telephone 01621-680100./ +44 1621 680100 Registered in England & Wales, company number 08914892. Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Chelmsford, Essex, CM3 6DT, United Kingdom |
Re: A simple, and reasonably accurate way of simply entering the properties of WELL ENGINEERED calibration kits.
Some of us have commercial cal kits for which C0 (as well as C1-C3) and the delays are specified by the manufacturer. In my opinion, C1-C3 are unnecessary for the NanoVNA's frequency range, but it would be great if the basic NanoVNA handled, at a minimum, let the user enter C0 and delay for the open as well as delay for the short.
As for verifying the value of C0 for calibration kits that have not been characterized by their manufacturer, I believe there is a method for doing this. And I think Kurt Poulson is the one who knows how to do it. - Jeff, k6jca |
SOLT calibration vs. TRL
The group has been focused on SOLT or so called SOLM (match) for calibration. However, for various reasons the TRL; Thru, Reflect, Line calibration algorithm would be advantageous. Fabrication of such a kit usually requires at least 3 lines to be built plus one fixture piece and microstrip is not difficult using a straight edge and an Exacto blade knife! The TRL lends itself to NON INSERTION components. In another words, non coaxial elements. Just a thought and the copy below hints to the benefits.
From Keysight: ============================================== A vector network analyzer requires that a measurement calibration be performed before error-corrected measurements can be made. For two-port measurements, the calibration algorithm used will determine the appropriate calibration kit, known either as SOLT or TRL/TRL*. Traditional full two calibration calibration typically utilizes three impedance and one transmission standards to define the calibrated reference plane. These standards, typically a Short, Open, Load, and Thru, make up the SOLT calibration kit. Another two port calibration type utilizes a minimum of three standards to define the calibrated reference plane. The measured parameters of the Thru, Reflect, and Line standards in a TRL/TRL* calibration kit provides the same information as a SOLT calibration via a different algorithm. Depending on the availability of calibration standards and the functionality of the network analyzer, one may use either calibration kit. In many non-coaxial , SOLT calibration standards are difficult, if not impossible, to build. The non-availability of calibration standards in proprietary or unique coaxial connectors also benefit from the TRL/TRL* calibration method. ============================================ |
Re: Newbie questions
Hi Mel,Use this free Android app with the nanoVNA:
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? You will need to ensure your kindle has OTG USB and the proper cable adapter. Regards,Larry On Tuesday, October 15, 2019, 1:39:28 p.m. GMT-4, Mel Farrer, K6KBE <farrermesa@...> wrote:
More on getting started, I have a laptop fine, can the Saver be downloaded to a Kindle Fire for portable use?? Just a question.? On a ladder in the antenna range the Kindle is a lot smaller. -- Mel, K6KBE |
gnuplot for nanoVNA Touchstone files
link added to application notes
/g/nanovna-users/wiki/Application-Notes |
Re: A simple, and reasonably accurate way of simply entering the properties of WELL ENGINEERED calibration kits.
On Tue, Oct 15, 2019 at 07:50 PM, Dr. David Kirkby from Kirkby Microwave Ltd wrote:
you already can setup delay with DISPLAY - SCALE - ELECTRICAL DELAY menu. If you needs C0 settings, just explain me how to test that it works properly? I will add such settings if it really helps. |
Re: Upgrade MCU from STM32F072C8T6 to STM32F303CCT6
Nice enhancement.I'll add this to my Console command document, specifying your version of firmware.
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Regards,Larry On Tuesday, October 15, 2019, 12:30:41 p.m. GMT-4, QRP RX <qrp.ddc@...> wrote:
On Wed, Sep? 4, 2019 at 08:35 AM, Rune Broberg wrote: The speed which you set for NanoVNA COM port doesn't matter. The speed value is just not used. No matter what speed you choose, it always communication at maximum speed.? :) If you have trouble with occasional transmission error. Try this firmware, it should solve your issue: It also has scanraw command, it allows to perform measurement for unlimited amount of points, and with using average up to 1000x. But it returns raw measured values, with no calibration apply. So, you're needs to apply your own calibration to the result. For example this command will return you S11 measurement (with no calibration apply) from 50 kHz to 10.050 MHz with 1 kHz step (10000 points) and with 5x average: scanraw 0 50000 1000 10000 5 where 0 - channel CH0 50000 - start frequency 1000 - frequency step 10000 - needed point count 5 - average times |
Re: Upgrade MCU from STM32F072C8T6 to STM32F303CCT6
On Wed, Sep 4, 2019 at 08:39 AM, Rune Broberg wrote:
NanoVNA already uses STM32F072CB which has 128 kB flash and 16 kB RAM. NanoVNA uses end of 128 kB flash block to store configuration and calibration data. So, if your NanoVNA can store and restore calibration, it already has 128 kB flash. :) |
Re: A simple, and reasonably accurate way of simply entering the properties of WELL ENGINEERED calibration kits.
Dr. David Kirkby from Kirkby Microwave Ltd
On Tue, 15 Oct 2019 at 14:12, Jeff Anderson <jca1955@...> wrote:
On Tue, Oct 15, 2019 at 02:39 AM, Dr. David Kirkby from Kirkby Microwave Ltd wrote:ps, No I meant what I said. The reason for the disparity is that I had moved the reference plane to a location I should have theoretically got a phase of 0. Here¡¯s a photograph of the screen taken under the following conditions * HP 8720D VNA * Calibrated from 50 MHz to 10 GHz with an 85052B 26.GHz 3.5 mm calibration kit. I used short, open and fixed load, not the sliding load, which is more accurate but time consuming. * The 85052B kit has the same open and short parameters as the 9 GHz 85033D and 85033E kits. (One of the Agilent guys wrote on their forum that the *standards are identical* - it is only the label and price which are different???) * Calibration coefficients used directly from the firmware of the VNA. * Attached male open * Applied a port extension of 31.79 ps, which is the delay of the short standard. So I had moved the reference plane. * The scale on the VNA has 0 degrees in the centre, with 0.25 degrees pet division. * The departure from the expected 0 degrees from an ideal open is 0.133 degrees at 1.5 GHz, rising to no more than 0.9 degrees anywhere over the range from 50 MHz to 10 GHz. I just ran a calculation in Matlab for the 85033D/E kit (Male). At 1.5 GHz, the OPEN with Full Definition should have a phase shift of -34.19 I had moved the reference plane by an amount I would have expected to see 0 degrees at all frequencies. Setting C0-C3 to 0 and making the open's delay equal to the short's delay changes this angle to -34.35 degrees, or an error of about 0.16 degrees, I measured 0.133 degrees. The uncertainty of the measurements far exceeds that.
Yes, agreed. If you have the 85054Bs parameters in, I would be interested what you get. That¡¯s a much more expensive kit. But ultimately small departures from the ideal 180 degrees makes no practical difference, do three is no overwhelming reason to believe that the phases of the opens are going to be very close together.
I don¡¯t doubt that the C0 is useful, but if there is very little memory available, and an even simpler model might be workable, but the 85032B kit is a very popular kit, so one would not want to do anything if it messes that kit up. Dave -- Dr. David Kirkby, Kirkby Microwave Ltd, drkirkby@... Telephone 01621-680100./ +44 1621 680100 Registered in England & Wales, company number 08914892. Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Chelmsford, Essex, CM3 6DT, United Kingdom |
Re: Upgrade MCU from STM32F072C8T6 to STM32F303CCT6
On Wed, Sep 4, 2019 at 08:35 AM, Rune Broberg wrote:
The speed which you set for NanoVNA COM port doesn't matter. The speed value is just not used. No matter what speed you choose, it always communication at maximum speed. :) If you have trouble with occasional transmission error. Try this firmware, it should solve your issue: It also has scanraw command, it allows to perform measurement for unlimited amount of points, and with using average up to 1000x. But it returns raw measured values, with no calibration apply. So, you're needs to apply your own calibration to the result. For example this command will return you S11 measurement (with no calibration apply) from 50 kHz to 10.050 MHz with 1 kHz step (10000 points) and with 5x average: scanraw 0 50000 1000 10000 5 where 0 - channel CH0 50000 - start frequency 1000 - frequency step 10000 - needed point count 5 - average times |
Re: Upgrade MCU from STM32F072C8T6 to STM32F303CCT6
Fantastic!!!
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This opens up the possibility of a whole new round of firmware-based functional enhancements for this device. Thanks for the effort. It would be great if you could upload a few photos of the mod to the Hacks and Mods folder in the Files area and maybe give some info on where you obtained the replacement uP from and price. Regards,Larry On Tuesday, October 15, 2019, 11:55:21 a.m. GMT-4, Ken Liao, AA6KL <kuohsing@...> wrote:
I have successfully ported the NanoVNA firmware to support STM32F303CCT6.? The detail can be found at The minimum required hardware mod is to replace the MCU and add a 1.5K ohm resistor between USB_DP and VDD, or between USB_DP and PA10. If you have the chance to try the code, please let me know if you see any issue. Ken |
Re: errors of "error" models
#48 : ann : update 3 of [LeastVNA] is withdrawn
Hello, After the comments made by Gary O'Neil on 9 October 2019: /g/nanovna-users/message/4483 which resulted to our: 41 : Corrections and Confirmations to 40 : [LeastVNA] - Update 3 - 9 October 2019 /g/nanovna-users/message/4519 Thu, Oct 10, 2019 at 11:59 AM : where we specifically admitted that: | Well, after all that, which are in addition to those, yet | unpublished, weaknesses we already noticed, it seems | that at least another one Update of our [LeastVNA] | description is unavoidable... we found that we have to make major changes to our [LeastVNA] and thus to upgrade it as a whole, so we withdraw its update 3, as well as * a n y * other previous edition of it. Sincerely, gin&pez@arg 48# |
Re: Another ebay deal?
On Thu, Oct 3, 2019 at 05:43 PM, Dr. David Kirkby from Kirkby Microwave Ltd wrote:
yes, exactly. The price is inadequate very expensive. The real price for such board is 2-5 usd. But they sell it for 30 usd, this is crazy price for the bord with just a connectors with no elements, and these connectors are rated for 20-time use. That's crazy. |
Re: Upgrade MCU from STM32F072C8T6 to STM32F303CCT6
I have successfully ported the NanoVNA firmware to support STM32F303CCT6. The detail can be found at
The minimum required hardware mod is to replace the MCU and add a 1.5K ohm resistor between USB_DP and VDD, or between USB_DP and PA10. If you have the chance to try the code, please let me know if you see any issue. Ken |
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