NanoVNA Custom Software

[jspencerg]

Re: S21 and S12
It's my understanding that these NanoVNA cannot do an S12. You have emulated S12 by building in support for xfer relay functionality. Right?
I am not seeing how to select a one port calibration. How?
Selecting the two port calibration without a xfer relay would entail putting the shunt and load on port A when it asks for port B because it thinks there is xfer relay installed.  These vna's can't put out a signal through port B, right?  (I realize I'm repeating myself.  The omission of this in manual seems like a big deal to me). Please set me straight about my understanding.

[joeqsmith]

If the software finds a valid comm port for the one you assigned to the transfer relay, it will attempt to talk to it.  If the comm port does not have have the proper handshake signal for the transfer relay, it will set the error.   I assign the port IDed in Device Manager for the transfer relay and save that as the default.  If I remove the transfer relay, Windows no longer reports it being a valid to my software.  If I plug it back in, Windows will once again report it is present.  Windows 10 does a decent job with the assignment and keeps the same port number. 

Odd your PC would behave any different as I would assume all Windows 10 behaves this way.  Otherwise it would be a nightmare to have to determine the VNAs port every time the software runs.    Then again, it seems someone had posted how they did not use the defaults file and would set it up manually every time.   

I can see that a basic computer course is needed.   I know an elderly lady who still uses AOL!!   

[joeqsmith]

Re: S21 and S12
It's my understanding that these NanoVNA cannot do an S12. You have emulated S12 by building in support for xfer relay functionality. Right?
I am not seeing how to select a one port calibration. How?
Selecting the two port calibration without a xfer relay would entail putting the shunt and load on port A when it asks for port B because it thinks there is xfer relay installed.  These vna's can't put out a signal through port B, right?  (I realize I'm repeating myself.  The omission of this in manual seems like a big deal to me). Please set me straight about my understanding.

Yes, the manual includes details about adding a transfer relay in order to measure all four S-parameters.  If you tell the software you have a transfer relay by assigning a valid port number to it, it will attempt to use it.  This includes calibration. 

I wrote the software this way because I am lazy.  I don't want to have to tell the software if I have the relay installed or not.  If its there I want Windows to tell me it's there and use it.   

***
Also, that last video I posted for the Lite demonstrated how to use the transfer relay. 
***
If you are curious why I have an enable selection for the stage controller but not for the transfer relay, the USB adapter I use for the transfer relay is dedicated hardware.  The only time it is installed in the PC is when I am using it.    The stage uses a USB adapter that I use to interface with other peripherals.   In that case, it is very possible that it may be installed at the time start the software.   

I could have chose to do something similar for the transfer relay but again, I didn't want to have to select it every time I wanted to use it.  Again, lazy.

[joeqsmith]

Shown in the upper right are the standards supplied with my Lite compared with parts from the V2Plus4.  I looked at the load standard supplied with my Lite and it's not very good but it's better than the remaining parts from Mini-Circuits.    I would need to buy another batch and hope for another decent one.   

[jspencerg]

Re: USB ports and calibration
I realize I was assigning port when I should not have been. Only needed to assign port for the VNA.

However, I find that not assigning a port for the relay does not seem to change the calibration options. 2-port button still there, but not the SOLT for port A.  I'll check to see if it asks for the port B short and load.
Regarding the message "select transfer relay and cross talk"  Are they program options?  Is it referring to selecting port for transfer relay and for setting cross talk coefficient?

I'm not an old lady and you're not lazy.  I know programming for oneself as the primary user leads to "common sense" decisions.  There is no such thing.

I just found a used transfer relay for $802 on ebay.
82152-700C70200 - TRANSCO - TRANSFER LATCHING RELAY 28VDC, SWITCH-RFF XMSN LINE

Is that a fair price?  Is that general pricing for this functionality?

Thank you.

[realfran]

I use Win10/64 the installation I did on one Pentium two core with 8 Ghb ram and 250Ghb SSD hard disk I live in the background the NanoVNA working all day on running the software, other PC I use is one Xenon with 16Gbt memory and 500Ghb SSD hard disk for the OS and  2TB HD for backup.
I'm computer illiterate, I typewriter with two fingers, I don't use Babbuino too hard for me, I tray many times Linux and I get lost on the console.

[realfran]

I use Win10/64 the installation I did on one Pentium two core with 8 Ghb ram and 250Ghb SSD hard disk I live in the background the NanoVNA working all day on running the software, other PC I use is one Xenon with 16Gbt memory and 500Ghb SSD hard disk for the OS and  2TB HD for backup.

I just found a used transfer relay for $802 on eBay.
82152-700C70200 - TRANSCO - TRANSFER LATCHING RELAY 28VDC, SWITCH-RFF XMSN LINE
Is that a fair price?  Is that general pricing for this functionality?

No is very expensive for $120 VNA gadget, I use one old HP VNA Switching test set, inside 2 switching relays (two relays improve isolation end get very low crosstalk) however the LiteVNA don't notice a big problem for the specs of it.
The transfer relay worked well I integrate the LiteVNA with the T/R relay using a very short semirigid original coax from the HP VNA switching test set to the N connectors.

[irpheus]

Hi Joe,

Let's guess and say you used the unsupported Windows 7.   When I installed my software on that old Lenovo tablet which runs Windows 8,  it did not include a compatible driver like 10 does.    Did you install the driver?  Did you then verify the PC assigned the comm port number using Device Manager?

With reference to your manual

Supports Windows 10 (may run on OS’s as early as XP)

I chose to install it on Win7. And, no, I did not know that I would need to install other drivers.

Jspencerg never followed up so I can't say if they made it any further.   Getting the software installed is trivial.  If you follow the thread, you may think everyone is having problems.  But I suspect it's more the only people who post are the ones having problems.  Most will just install it and we will never hear from them.

I'll be very impressed if you manage to construct the peripherals and get any meaningful data.  Somehow you will need to validate the setup.

I simply just work at my best when the people around me have confidence in me and my abilities to find solutions and engage positively in the personal exchange.

For me it just doesn't work in this context and I have now chosen to accept this.

So I will leave it here.

Be well,

Jesper

[joeqsmith]

Re: USB ports and calibration
I realize I was assigning port when I should not have been. Only needed to assign port for the VNA.

However, I find that not assigning a port for the relay does not seem to change the calibration options. 2-port button still there, but not the SOLT for port A. 

SOLT   Short, Open, Load, Thru    
Wouldn't the thru be difficult without a second port?       

I'll check to see if it asks for the port B short and load.

From the manual:

This software has the ability to control a transfer relay.  If this option was enabled prior to selecting the calibration, you would be prompted to repeat this process for port B (2). 

Regarding the message "select transfer relay and cross talk"  Are they program options?  Is it referring to selecting port for transfer relay and for setting cross talk coefficient?

I'm not an old lady and you're not lazy.  I know programming for oneself as the primary user leads to "common sense" decisions.  There is no such thing.

I just found a used transfer relay for $802 on ebay.
82152-700C70200 - TRANSCO - TRANSFER LATCHING RELAY 28VDC, SWITCH-RFF XMSN LINE

Is that a fair price?  Is that general pricing for this functionality?

Thank you.

Leakage was also covered in the manual.

I think Flipper paid under $100 for a NOS Transco transfer relay.   At $800, I expect you could get a new one from Pasternak. 

[joeqsmith]

I use Win10/64 the installation I did on one Pentium two core with 8 Ghb ram and 250Ghb SSD hard disk I live in the background the NanoVNA working all day on running the software...

Very nice!! 

[joeqsmith]

Jesper,

Hi Joe,

Let's guess and say you used the unsupported Windows 7.   When I installed my software on that old Lenovo tablet which runs Windows 8,  it did not include a compatible driver like 10 does.    Did you install the driver?  Did you then verify the PC assigned the comm port number using Device Manager?

With reference to your manual

Supports Windows 10 (may run on OS’s as early as XP)

I chose to install it on Win7. And, no, I did not know that I would need to install other drivers.

Yes the manual states:

Supports Windows 10 (may run on OS’s as early as XP).

  While I have shown it running on XP,  the only OS that is supported is 10.   The use of the word "may" can be better understood from the manual's scope:

This manual assumes the reader is PC literate and has some basic understanding of how a VNA works.  It is not a learner’s guide on using a VNA and offers no assistance into solving basic computer related problems.   

Also from the manual:

The software will include an installer which contains the runtime engine only.  No drivers will be included beyond NIVISA.   
...
You will want to have all the drivers installed and make sure your PC is seeing the device before getting started.  The software was tested using both the recommended Cypress as well as Microsoft's included drivers.  No differences in their performance were noted.

 

Installing drivers and making sure the OS can ID the your device is pretty much standard practice for any peripheral you install. 

Jspencerg never followed up so I can't say if they made it any further.   Getting the software installed is trivial.  If you follow the thread, you may think everyone is having problems.  But I suspect it's more the only people who post are the ones having problems.  Most will just install it and we will never hear from them.

I'll be very impressed if you manage to construct the peripherals and get any meaningful data.  Somehow you will need to validate the setup.

I simply just work at my best when the people around me have confidence in me and my abilities to find solutions and engage positively in the personal exchange.

For me it just doesn't work in this context and I have now chosen to accept this.

So I will leave it here.

Be well,

Jesper

For myself, I enjoy learning new things but not everyone is wired like that, like my elderly lady friend with her AOL. 

From the manual:

My software was not written for this group (radio community).  It was designed as an engineering tool for the RF experimenter.   

While this forum's owner suggests that anyone who calls themselves an engineer is one, I do not prescribe to that idea.   The harsh reality is that while these VNAs can be had for $50, it doesn't mean that just anyone can sit down and be some sort of expert in minutes.   The fact you are having problems reading the manual and not knowing some of the basics on how to use your PC tells me this will be a very difficult task for you.    Your willingness to give up may have saved you a lot a headache.

[nctnico]

  Does it really not dawn to you that the installation problems people have originate from your end? And on top of that you belittle people that get lost along your breadcrumb trail. Quoting over and over again from an incomplete manual isn't going to help; just fix the manual. I admire the effort that you put into your software but your belittling tone towards people is putting me off big time. Just like Jesper I have lost all interest in even trying to get your software to work. There are tons of other tools around for the NanoVNA so there is no need to put up with such abuse.

[jspencerg]

Re: A real "two-port" calibration

What do you call a SOLT calibration that is done where port 2 can only receive?  I wouldn't think that would be a 2-port calibration.

[jspencerg]

Re: Using a transfer relay

Thanks for comments regarding the $800 relay I saw on ebay.  Pricing there often needs serious reality check.

I was also seeing pricing for relays, claiming to be new, for under $100.
https://www.ebay.com/itm/255349680593?epid=28052016567&hash=item3b7406e9d1:g:hBEAAOSwmX5hgWGc

My question is what specifications are necessary for the relay to work with the software?

[joeqsmith]

Does it really not dawn to you that the installation problems people have originate from your end? And on top of that you belittle people that get lost along your breadcrumb trail. Quoting over and over again from an incomplete manual isn't going to help; just fix the manual. I admire the effort that you put into your software but your belittling tone towards people is putting me off big time. Just like Jesper I have lost all interest in even trying to get your software to work. There are tons of other tools around for the NanoVNA so there is no need to put up with such abuse.

I have made my software available for free to those that want to use it but that does not mean it comes with unlimited support or for that matter any support.  I have no desire to try and educate people on the basics of how to use a PC.   Especially if you are asking questions that have already been covered.  In your case, even when I handed you the answer, you couldn't be bothered to read it and asked the same question yet again.  You may feel your time is too valuable or maybe just need an excuse.   As I have already explained to you,  I will not be making any updates to the old repository.   This includes the documentation.   

[jspencerg]

My 2 cents:
Mr. Smith has reluctantly made available a software tool that he wrote for himself.  It is obvious, as he has often said, that he does not want to promote it or put much effort into teaching others to use it.  I am surprised he bothers to answer my ignorant, incompetent questions.  I am still glad he does.

[joeqsmith]

Re: A real "two-port" calibration

What do you call a SOLT calibration that is done where port 2 can only receive?  I wouldn't think that would be a 2-port calibration.

Single path two port.   With the transfer relay, a full two port. 

See one path two port:
https://coppermountaintech.com/help-s2/one-path-two-port-calibration2.html

Re: Using a transfer relay

Thanks for comments regarding the $800 relay I saw on ebay.  Pricing there often needs serious reality check.

I was also seeing pricing for relays, claiming to be new, for under $100.
https://www.ebay.com/itm/255349680593?epid=28052016567&hash=item3b7406e9d1:g:hBEAAOSwmX5hgWGc

My question is what specifications are necessary for the relay to work with the software?

The software will use one handshake pin to control the relays two states.   The software checks the status of one of the handshake pins and will set an error flag but it does not do anything else with it.   So, there really are no other requirements outside of having the one pin select the state.

From a hardware standpoint, you would need to design what ever interface to control your specific relay.  Because there are many devices available, that's really up to the designer to sort out.   

I had used realfran's data as an example in the last video to demonstrate the transfer relay.   Looking at what realfran recently posted:

I use one old HP VNA Switching test set, inside 2 switching relays (two relays improve isolation end get very low crosstalk) however the LiteVNA don't notice a big problem for the specs of it.
The transfer relay worked well I integrate the LiteVNA with the T/R relay using a very short semirigid original coax from the HP VNA switching test set to the N connectors.

I now suspect this is the cause of their problem.  I have seen others talk about using 2 VNAs in place of a transfer relay to save cost as well as use two separate switches.   The 2 X switches would require some sort of T and extra stubs.   Not a great solution.    *** But better than the 2 X VNA proposal.

[joeqsmith]

My 2 cents:
Mr. Smith has reluctantly made available a software tool that he wrote for himself.  It is obvious, as he has often said, that he does not want to promote it or put much effort into teaching others to use it.  I am surprised he bothers to answer my ignorant, incompetent questions.  I am still glad he does.

I dare say I have spent a fair amount of effort attempting to teach others to use my software (and general use of a VNA).    Putting the manual together and creating the videos was a major effort when you consider I give it all away free of charge.

***

I would like to add that being incompetent or ignorant on a subject is not a problem.    I am very ignorant on most subjects.   For subjects where I am interested, I may invest the time to educate myself.  Normally by reading and experimenting.   

Expecting anything from me will not go over well but asking me for help when I can clearly see you are trying to better yourself is typically not a problem. 

[realfran]

Please read the manual step by step (I'm computer illiterate)

The transfer relay is controlled by the state of the RTS pin. When RTS is de-asserted, Port 1
and 2 of the VNA will route to Ports 1 and 2 of the transfer relay. When RTS is asserted, Port
1 and 2 of the VNA will route to Ports 2 and 1 of the transfer relay. The software expects the
transfer relay to always assert the CTS pin, or it will set the transfer relay error (XferRly Err).
The software really doesn’t care what type of transfer relay is attached. It uses a common USB
– TTL adapter from FTDI. The RTS signal is used to select the state of the relay and the CTS
is used to monitor it’s status. The communications port is selected in the Setup/Diagnostics
page using the XferPort. Again, the BAUD rate has no effect. The selected port is saved as part
of the defaults. Shown is the FTDI cable attached to the Transco controller.

After this, I go online to study the serial port connection and the FTDI converter to USB (I'm totally ignorant of digital) I built one transistor NPN one diode two resistors
 and one small relay to driver the T/R relay.

[jspencerg]

Re: Transfer Relay
I found a new unit that appears identical to the Transco relay Joe recommended in the manual.  Bought it. I'm willing to give it a go though I'm not sure how to connect everything(anything).

[jspencerg]

Re: Transco relays
Joe's relay has different activation wiring.  Unit I ordered has only two wires.  No sign of Transco, absorbed by another company?  Dow-Key microwave appears to make similar units.  Identified likely schematic for my unit. There are several units with 3+ control wires. Attached catalogue of coaxial relays.
  2-dpdt-transfer-coaxial-switch.pdf

[joeqsmith]

The manual provided the part number for the relay I used but again the software will not care. 

[jspencerg]

The relay activation methods seem to be only difference between models.  I don't know why or when one switching activation would be preferred.  My two-wire input is simplest of them all.

Creating this port- switching arrangement is a rabbit hole I had not planned on.

[joeqsmith]

Your relay will require a constant supply for one state vs my latching type that only requires a small pulse to change the state.   My average current draw is basically 0 off the USB port.  You could use a simple RC diode circuit to reduce the hold current after it switches if that is a concern for you.  They may not spec the hold current but easy enough to swag.   

Do you have a clear goal in mind or just wanting to play?  Just curious.  Obviously you are adding variables and as we saw from realfrans, it can cause some problems.  If the goal is to measure active circuits, keep in mind that square wave drive.   If you just want to play with it, maybe build a T-Check to go with it.   In the last video I made, I show the home made T-Check and transfer relay giving some decent results to a GHz or so. 

[realfran]

The transfer relay on my set-up is one design from HP there is two really switches on H the 141T" semirigid from the relays to the N connectors hare the original length. The only thing  I change is the relay drives, the connection from LiteVNA port and the relays are connected directly.
The LiteVNA for is limited specs don't notice a big problem of crosstalk or isolation on the end of all is hobby instrument, not metrology grade device.
The calibration on the software helps a lot to minimize the difference.