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Re: Transform: Time Domain Band Pass
On 8/16/21 12:09 PM, Syd via groups.io wrote:
In the manual there is a Transform setup for the bandpass mode and here is the picture of the results attached. I think this setup is strictly for measuring band pass filters, correct me if I'm wrong. From the pix I can see that the time being scanned from the frequency setup is from 0 ns to 43 ns shown on the bottom. From what I am seeing I think ch0 shows the pulse being generated and ch1 is showing the results from the BPF.not exactly, what you're seeing is the pulse that would be *reflected* back from the UUT for CH0, and the pulse that would be transmitted for CH1. The 20.0n/-0.14 and 10.0n/-0.02 scaling for ch0 and ch1 at the top I thought was showing the scaling per division and the level, but now I am not sure what it is telling me.Perhaps the reflection coefficient magnitude? Then again the white marker notation is showing 4ns 0.4m? How do I interpret that?The basic measurement is in time, so some assumed velocity factor is being used to turn that into distance.? The reflected pulse is 4ns, so the 1 way time is 2ns, and that probably works out to 0.4m.? (in free space, 2ns would be ~60cm, so with a VF of 66%, that would be 40cm, I think. Additionally, what is the TDR measurement of a band pass filter giving me information wise that I can't get from scanning the BPF and looking at the logmax output over a span of frequencies?Not much.? It's not a commonly used way to look at filters. At least from the logmax method I can see the characteristics of the filter, and I don't see anything like it with this method since it is in the time domain.Time domain is interesting if you're wondering about group delay and dispersion.? If you have a SAW filter, sometimes you can see "triple transit" effects as a peak at 3x the nominal delay.? It's also interesting if you're concerned about envelope distortion. syd/wt1v |
Re: Transform: Time Domain Band Pass
On Mon, Aug 16, 2021 at 12:09 PM, Syd wrote:
This feature is not restricted to measuring bandpass filters. The TDR mode uses an IFFT algorithm on VNA frequency data to get a time domain display. This is useful when finding distance to a fault or the length of a transmission line When measuring a device under test (DUT) it gives the impulse response which is the time domain equivalent of the frequency response. Selecting "bandpass" mode is useful when measuring transmission lines with DC blocking or filtered transmission lines. It is the mode to use when setting a stimulus frequency well above DC. You can read more about this in this app note by Agilent. The bandpass mode is described on page 13. Roger |
Re: Transform: Time Domain Band Pass
Filters ring when you pulse them.
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On Monday, August 16, 2021, 02:10:02 PM CDT, Syd via groups.io <nhuq1@...> wrote:
In the manual there is a Transform setup for the bandpass mode and here is the picture of the results attached.? I think this setup is strictly for measuring band pass filters, correct me if I'm wrong.? From the pix I can see that the time being scanned from the frequency setup is from 0 ns to 43 ns shown on the bottom. From what I am seeing I think ch0 shows the pulse being generated and ch1 is showing the results from the BPF. The 20.0n/-0.14 and 10.0n/-0.02 scaling for ch0 and ch1 at the top I thought was showing the scaling per division and the level, but now I am not sure what it is telling me.? Then again the white marker notation is showing 4ns 0.4m?? How do I interpret that? Additionally, what is the TDR measurement of a band pass filter giving me information wise that I can't get from scanning the BPF and looking at the logmax output over a span of frequencies?? At least from the logmax method I can see the characteristics of the filter, and I don't see anything like it with this method since it is in the time domain. syd/wt1v |
Transform: Time Domain Band Pass
Syd
In the manual there is a Transform setup for the bandpass mode and here is the picture of the results attached. I think this setup is strictly for measuring band pass filters, correct me if I'm wrong. From the pix I can see that the time being scanned from the frequency setup is from 0 ns to 43 ns shown on the bottom. From what I am seeing I think ch0 shows the pulse being generated and ch1 is showing the results from the BPF. The 20.0n/-0.14 and 10.0n/-0.02 scaling for ch0 and ch1 at the top I thought was showing the scaling per division and the level, but now I am not sure what it is telling me. Then again the white marker notation is showing 4ns 0.4m? How do I interpret that? Additionally, what is the TDR measurement of a band pass filter giving me information wise that I can't get from scanning the BPF and looking at the logmax output over a span of frequencies? At least from the logmax method I can see the characteristics of the filter, and I don't see anything like it with this method since it is in the time domain.
syd/wt1v |
Re: help with driver issue for a newbie
Have you looked over in either of the nanovna-V2 forums?
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I just found this thread there: /g/NanoVNA-V2/topic/win_10_issue/77411380?p=,,,20,0,0,0::recentpostdate%2Fsticky,,,20,2,80,77411380 On Monday, August 16, 2021, 12:40:41 p.m. EDT, Ray <boxman@...> wrote:
Hi All, I am having a frustrating driver issue. It is all the more frustrating because at some point I succeeded in controlling my nanoVNA from various software packages from my laptop, and was all set to study the various options, choose the one most suitable for me, and get to work! But currently, the computer and the nanoVNA do not appear to talk with each other. I have no idea of which nanoVNA v. 2 variant I have, but please see the attached photo. Under version, it states that the hardware was designed by OwoComm. I purchase it from Ali Express for $62.? I am trying to connect with a relatively recent Lenovo laptop running Windows 10 pro. It just did an update to version 20H2 (today) but I had the same problem before and after the update. I have the following symptoms: 1.? ? ? When I plug in the USB cable, the nanoVNA screen remains active. 2.? ? ? When I plug in or disconnect the USB cable, I get a characteristic dong from the laptop, but I do not observe any difference in the device manager display. 3.? ? ? What appears in the device manager display under ports is "STMicroelectronics Virtual COM port (COM4)" together with the yellow triangular warning icon, whether the nanoVNA is connected regularly, or in DFU mode, or disconnected (see attached screen shot). 4.? ? ? If I right click on this and look at properties, I get a.? ? ? (general), "The device cannot start (Code 10). The specified request is not a valid operation for the target device b.? ? ? (driver): driver version 1.4.0.0, driver date 2-Aug-13 c.? ? ? (Events): information: Device ROOT\PORTS\0000 requires further installation I followed the procedure in Absolute Beginner's Guide to NanoVNA by Martin Svaco, 9A2JK, and in particular tried all of the methods suggested in the TROUBLESHOOTING THE DRIVER INSTALLATION section. Before today's update, I also used CCleaner to clean-up the registry. But all to no avail. I tried updating, uninstalling, reinstalling, the driver etc., but nothing alleviated the above described symptoms. I would value any and all advice! 73, Ray 4X1RB From the home of Prof. Emeritus Raymond (Reuven) Boxman School of Electrical Engineering Tel Aviv University Cell:? ? ? +972 544 634 217 CEO Clear Wave Ltd.? ? ? ? ? ? ? ? <> Scientific Writing Courses:? ? ? ? <> |
help with driver issue for a newbie
Hi All,
I am having a frustrating driver issue. It is all the more frustrating because at some point I succeeded in controlling my nanoVNA from various software packages from my laptop, and was all set to study the various options, choose the one most suitable for me, and get to work! But currently, the computer and the nanoVNA do not appear to talk with each other. I have no idea of which nanoVNA v. 2 variant I have, but please see the attached photo. Under version, it states that the hardware was designed by OwoComm. I purchase it from Ali Express for $62. I am trying to connect with a relatively recent Lenovo laptop running Windows 10 pro. It just did an update to version 20H2 (today) but I had the same problem before and after the update. I have the following symptoms: 1. When I plug in the USB cable, the nanoVNA screen remains active. 2. When I plug in or disconnect the USB cable, I get a characteristic dong from the laptop, but I do not observe any difference in the device manager display. 3. What appears in the device manager display under ports is "STMicroelectronics Virtual COM port (COM4)" together with the yellow triangular warning icon, whether the nanoVNA is connected regularly, or in DFU mode, or disconnected (see attached screen shot). 4. If I right click on this and look at properties, I get a. (general), "The device cannot start (Code 10). The specified request is not a valid operation for the target device b. (driver): driver version 1.4.0.0, driver date 2-Aug-13 c. (Events): information: Device ROOT\PORTS\0000 requires further installation I followed the procedure in Absolute Beginner's Guide to NanoVNA by Martin Svaco, 9A2JK, and in particular tried all of the methods suggested in the TROUBLESHOOTING THE DRIVER INSTALLATION section. Before today's update, I also used CCleaner to clean-up the registry. But all to no avail. I tried updating, uninstalling, reinstalling, the driver etc., but nothing alleviated the above described symptoms. I would value any and all advice! 73, Ray 4X1RB From the home of Prof. Emeritus Raymond (Reuven) Boxman School of Electrical Engineering Tel Aviv University Cell: +972 544 634 217 CEO Clear Wave Ltd. <> Scientific Writing Courses: <> |
Re: NanoVNA H / H4 / V2 / V2Plus / V2Plus4 firmware v1.0.69
#firmware
Obviously you haven't since the emails keep coming.
On Mon, 16 Aug 2021 at 13:15, Knud Jorgen Olsen-Jensen via groups.io <vk2kjj@...> wrote: Stop sending the e-mail to me. I have even left the Group because I could |
Re: Measuring Unknown
#matching
#transformer
See the bottom of each email for the link
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On Aug 15, 2021, at 20:10, Knud Jorgen Olsen-Jensen via groups.io <vk2kjj@...> wrote: |
Re: NanoVNA H / H4 / V2 / V2Plus / V2Plus4 firmware v1.0.69
#firmware
Stop sending the e-mail to me. I have even left the Group because I could not stop the mailsYou need go /g/nanovna-users/editsub and select No Email for disable receive group messages |
Re: NanoVNA H / H4 / V2 / V2Plus / V2Plus4 firmware v1.0.69
#firmware
Knud Jorgen Olsen-Jensen
Stop sending the e-mail to me. I have even left the Group because I could not stop the mails
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CW4EVER On 16 Aug 2021, at 19:31, Anton <om1aeg@...> wrote: |
Re: NanoVNA H / H4 / V2 / V2Plus / V2Plus4 firmware v1.0.69
#firmware
Thank you for your reply DiSlord. I looked at both PCBs, 10R resistor for 3.3V I put in position R2 on "LCD" PCB, MOSI signals, MISO, SCLK are available on H1 connector on "LCD" PCB. The problem will be to get the PB9 (CS) signal out of U303:46, directly from U303 pin, no trace on PCB.
|
Re: Measuring Unknown
#matching
#transformer
Knud Jorgen Olsen-Jensen
Don¡¯t send me your emails
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CW4EVER On 16 Aug 2021, at 10:10, Knud Jorgen Olsen-Jensen via groups.io <vk2kjj@...> wrote: |
Re: Measuring Unknown
#matching
#transformer
Knud Jorgen Olsen-Jensen
Don¡¯t send me your emails
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CW4EVER On 16 Aug 2021, at 09:15, Charles KC6UFM <kc6ufm@...> wrote: |
Re: Measuring S11 at input of RF power amplifier - could I calibrate "through" an attenuator?
On Sun, Aug 15, 2021 at 02:21 PM, Jim Lux wrote:
The attenuators affect more than S11 SNR when used in this fashion They are not exactly 50 ohms input/output impedance. Also the calibration errors will probably be greater as the DUT impedance is further away from 50 ohms. Roger Roger |
Re: download the calibration from the NanoVNA
Knud Jorgen Olsen-Jensen
Don¡¯t send me your emails
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CW4EVER On 16 Aug 2021, at 09:17, DiSlord <dislordlive@...> wrote: |
Re: download the calibration from the NanoVNA
Need use any console software (like terminal, putty RealTerm)
You receive list of error tetm (used by nanoVna as calibration data) 'data 2' ED - error term directivity 'data 3' ES - error term source match 'data 4' ER - error term refrection tracking 'data 5' ET - error term transmission tracking 'data 6' EX - error term isolation But NanoVNA Saver Use SOLT calibration data format, so you can`t use this calibration data in it. |
Re: Measuring Unknown
#matching
#transformer
Charles KC6UFM
Hi, Luciano...
I more or less (in my head) wrote off the "extra" resistance needed to make the NanoVNA see a flat match as being to a combination of lead resistance/reactance and operator error. I think it's safe to assume that the transformer is actually a 49:1 ratio. Thanks! On Sun, Aug 15, 2021 at 3:48 PM Luciano Luciano <luciano.wdc@...> wrote: Hi Charles,-- de KC6UFM Charles |
Re: Measuring Unknown
#matching
#transformer
Hi Charles,
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I get "suspicious" when I see small differences like this i.e. 50 ohm as in this case. Assuming the black box is lossless, you should measure either 2450 or 2500 ohm if you load the other port (with coax connector, right?) with 50 ohm... if you measure 2450 then it is a 49:1 transformer as you correctly guessed in the first place! Of course easier to say (and write) in theory than to actually do in practice. Regards, Luciano On Sun, Aug 15, 2021, 6:15 PM Charles KC6UFM <kc6ufm@...> wrote:
Hello, All... |
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