Hi Roger Just measured 50dB of attenuators between ports with a range of 1.5 to 30 MHz and it was flat but with 0.05dB of fluctuation due to noise. Upped it to 60dB with a similar result but about 0.8 dB fluctuation. Placing the VNA on a metal surface made no difference in either case. I assume the isolation calibration is helping but wonder if a complex impedance might be more challenging. TBH I was intending to buy some copper tape to solder on but decided to buy a better made Nano and keep this one for playing around with. Might still be worth a go once the other one arrives. Mike

I originally created this drawing for my own use, but then thought that I would upload it to this group in case someone else found it helpful. I make no promises about its accuracy. Should anyone find a mistake, please let me know and I'll correct it as soon as I can. Thank you for this group and I am learning something new about the nanoVNA every day. I hope you find this useful. Larry

Hi group. Checking the frequency precision of my NanoVNA and found an error about 200Hz lower than indicated. Looking at the schematic found some kind of freq correction via software. Anybody knows how to perform it? TNX ea7edp

Has anyone determined if there is more than 2 PCBA for these units? I see there is a USB Micro B (which I have) and the USB C,?? on the black (which I have seen advertised on some white units also). I Know the SMA spacing between the 2 units I have played with , and the power switch is also different

groups.io supports the creation of wikis. I think it would be useful to have one, with different pages allocated to different topics - a user manual, instructions to build from source, bugs, etc. I don't have much experience of wikis. I have thought of setting one up for the HP/Agilent/Keysight group I am owner of, but have not done so. I think the NanoVNA needs one more than most others. -- Dr David Kirkby Ph.D C.Eng MIET Kirkby Microwave Ltd Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, CHELMSFORD, Essex, CM3 6DT, United Kingdom. Registered in England and Wales as company number 08914892 https://www.kirkbymicrowave.co.uk/ Tel 01621-680100 / +44 1621-680100

I haven't seen any mention this, but you don't need a stylus to use the menus. You just press down the center of the marker knob, and the menus come up. You use the left and right (+ & -) to move the green "bar" up and down, then press down again Frank

All, I have enabled files, photos and wikis for this group. You should be able to upload files and photos and create wikis now. Please, please, create subfolders when you upload files or photos. For single files or photos which do not warrant their own subfolder, I have created subfolders named "Miscellaneous". The Photos folder contains 110 photos which are those attached to previous posts (groups,io did this automatically). If anyone has questions about these, or discovers a problem, please let me know. DaveD

Looking over my unit, it's a Worse clone". I am returning it, as some of the measurements are bad., Which website should I use to get the proper unit? Thank you, Ed

Personally, I'd rather see this instrument in a tablet size, something I can easily see; in a real metal box with Type-N connectors and sturdy switches and push-buttons. My need is for an instrument that I can carry to antenna sites for broadcast antenna work. I understand where some folks like tiny pocket size instruments, not sure why, but I'm probably going to go to something like an HP e5061B - a totally different area of an instrument. I like the 8753c or ES but they are pretty big and heavy for schleping to transmitter sites. Burt, K6OQK At 05:32 AM 7/29/2019, Frank S wrote Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. biwa@... K6OQK -- Burt I. Weiner Associates Broadcast Technical Services Glendale, CA U.S.A. K6OQK

Hi group, i have a new nanovna (black) and a strange issue on the pc software. When i connect the vna to the pc (windows 10 , 64 bit) , i can change the start / stop / span parameters via the computer, but hitting the get data button does not show any trace on the software. It does not matter which measurement i choose; no graph is been showed. Is the 64 bit W10 causes this issue? Anybody an idea to solve? 73' Ton

Hi, I think that Smith chart presentation of impedance as <real_part>[ohm] <series cap or ind>[F|H] is not practical in many case of use. So I decide to modify the code to show impedance in <real_part>+/-j<imag_part> format, you can find the patch to plot.c to obtain this. If I found a bit of time I could split Smith chart in two, one as original and one as just proposed. Do you think it worth? Lapo, IK5NAX -------- diff --git a/plot.c b/plot.c index 10074c3..c5c92e5 100644 --- a/plot.c +++ b/plot.c @@ -576,16 +576,22 @@ gamma2imp(char *buf, int len, const float coeff[2], uint32_t frequency) // float z = sqrtf(zr*zr + zi*zi); int n; - n = string_value_with_prefix(buf, len, zr, S_OHM[0]); - buf[n++] = ' '; + n = string_value_with_prefix(buf, len, zr, '\0'); + if(zi<0) + buf[n++]='-'; + else + buf[n++]='+'; + buf[n++]='j'; + string_value_with_prefix(buf+n, len-n, fabs(zi), S_OHM[0]); - if (zi < 0) { - float c = -1 / (PI2 * frequency * zi); - string_value_with_prefix(buf+n, len-n, c, 'F'); - } else { - float l = zi / (PI2 * frequency); - string_value_with_prefix(buf+n, len-n, l, 'H'); - } + + /* if (zi < 0) { */ + /* float c = -1 / (PI2 * frequency * zi); */ + /* string_value_with_prefix(buf+n, len-n, c, 'F'); */ + /* } else { */ + /* float l = zi / (PI2 * frequency); */ + /* string_value_with_prefix(buf+n, len-n, l, 'H'); */ + /* } */ } void

On 2 June I bought a NanoVNA on EBay. On 19 June I receive a small parcel with a blue tassel in it. The tracking number on the parcel was the same as listed for the NanoVNA. Now EBay thinks that the VNA has been delivered. I contacted the seller and he stated the the VNA was to be shipped when it arrived to him from the manufacture and that he was tracking it. The seller is topcyberday and has a 98.9% positive feedback with 1840 transactions. My concern is that EBay will think that the VNA has been delivered and that I will have no recourse if I do not receive the VNA. Anyone with experience with this seller? Thanks Glenn -- ----------------------------------------------------------------------- Glenn Little ARRL Technical Specialist QCWA LM 28417 Amateur Callsign: WB4UIV wb4uiv@... AMSAT LM 2178 QTH: Goose Creek, SC USA (EM92xx) USSVI LM NRA LM SBE ARRL TAPR "It is not the class of license that the Amateur holds but the class of the Amateur that holds the license"

Dave (G8KBB) has evolved a most wonderfully robust VNA GUI that he calls myVNA. I believe he is open to sharing the interface with those who might be willing to do the work of adding support for other platforms. MyVNA evolved from the N2PK VNA; but I’m certain it would be straight forward to add support for the NanoVNA by someone skilled in the art. Dave licenses myVNA for free to amateurs, but maintains control of the source. If somebody is interested in myVNA as a GUI driver for these and willing to volunteer your support; send Dave an email and see what you can work out. http://g8kbb.co.uk/index.html Contact Dave either way, and request a license for his software. It imports up to 4 snp files, and enables them to be displayed and compared in all display formats. -- 73 Gary, N3GO

Hey Hugen, I want to order an original nanoVNA form you. I have to tried http://gen111.taobao.com/ but that doesn’t work. I can’t read Chinese :-). Also change language doesn’t work. Do you maybe sell them also on ebay or so? Or is there another seller that sells good originals nanoVNA. After reading here I Found out I now have a bad clone :-(

I see lots of people having trouble sourceing what they consider a good version. I bought his one https://www.ebay.co.uk/itm/254253727598 I can't really complain * It came with a battery * It has 4 traces * It has screening * It works to 900 MHz with no need to mess about with the firmware. * There is no evidence of spurious signals. Downsides * The build quality is poor - but that seems to be the case was all of them. I've yet to see any reports of good build quality. * No mention of where to get the GPL source code. * The "open" supplied is worst than just leaving the connector open, as the added capacitance just makes the "open" less like an ideal open. That is going to tbe the same for any "open" unless you go to great lengths to stop it. * Although the load has an excellent return loss, there is a problem with it which I overlooked the first time I posted about that. The first did not work (bad display, which Hugen said is delicate), but they sent another which is okay. I asked them to send that express mail, which they did, but it had to be without the battery. So I had to swap that over. I can't really complain, and its probably a lot safer than buying from Alibaba, or some obscure Chinese website. -- Dr David Kirkby Ph.D C.Eng MIET Kirkby Microwave Ltd Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, CHELMSFORD, Essex, CM3 6DT, United Kingdom. Registered in England and Wales as company number 08914892 https://www.kirkbymicrowave.co.uk/ Tel 01621-680100 / +44 1621-680100

I like to research all my projects and have found a number of software and hardware resources of the NanoVNA, EU1KY VNA,and DG8SAQ VNA that users and/or developers may find useful. (MOD: Feel free to relocate this to the WIKI area) Yet Another VNA Project: https://forums.qrz.com/index.php?threads/yet-another-vna-project.638475/ - uses the NanoVNA H/W & S/W design in part and references his github firmware resource. SimSmith & tutorial: http://harriman.ddns.net/Smith_Charts.html - Referenced by the Yet Another VNA link above. Zplots - Impedance Plots using Excel Charts: https://ac6la.com/zplots1.html - Use this to model your designs. - I wonder if it could be modified to accept input directly from the NanoVNA? DXzone VNA reference page: https://www.dxzone.com/catalog/Technical_Reference/Vector_Network_Analyzer/ - An excellent Amateur Radio website with numerous technical reference links. Building an S-Parameter Test Set for the VNWA-3E: http://www.reeve.com/Documents/Articles%20Papers/Reeve_S-ParamTestSet.pdf - An easily built S-Parameter Test Set - possibly useful for the NanoVNA Cheap homemade 30 MHz - 6 GHz vector network analyzer : http://hforsten.com/cheap-homemade-30-mhz-6-ghz-vector-network-analyzer.html - Refer to building and using the Calibration adapters close to the end of the article.