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New nanoVNA received
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Just received my 2nd nanoVNA. This is the black case, no Gecko white which works current to date quite well with 2 track display. This black case arrived ON TIME and well packed. Apparently held it's charge all the way through shipment and booted with a 4 track display. These instruments are little like a box of cracker jacks or is it chocolate, your not quite sure what's in the box. So far, so good. This unit came in its own plastic protective case with all the accessories enclosed. The construction looks very good and robust. The ON-OFF slide switch and USB-C connector are more robust. There is a screen protector film over the display and no scratches on the display from a stylus being used on the soft screen for pretest. The style of the 50 ohm load is DIFFERENT. The short and open appear the same as with prior cal kit. Is this 50 ohm termination superior? Don't know. The prior was ~ 18 dB best case at 900 MHz. Very important, IT IS CLEAR THAT THE ASSEMBLY OF THIS UNIT HAS THE RF SHIELDS OVER THE BRIDGE AREA AND MIXER AREA AS SUGGESTED IN THE EARLIER POST. ALSO, THESE SHIELDS LOOK LIKE DIE CUT BRASS WITH PRECISION FIT. THESE WERE NOT CUT OUT WITH TIN SNIPS OR A SCISSOR AND HAND SOLDERED IN. THIS LOOKS LIKE A PRO JOB. Hurrah! There is a green film strip sticking out of the left side of the display. Looks like the kinda of thing you would pull to engage the battery contacts on a new toy to protect the battery during shipment. However, I have not touched it and the unit turns on out of the box. The display has the 4 color traces and the pixel appearance is smaller and crisper than the white gecko unit. So I will wait for a charge cycle to complete and see how this one plays. Hope this info is of assistance. Alan
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This is the highest filter I had from the junk box without exceeding the limits of the instrument. The next filter up was centered at 902 MHz. So trying to get a sense of measurement DR would be a stretch. This is a 6 pole UHF helical filter centered at ~ 490 MHz after re-tuning. This noise floor of the response is HEAVILY dependent on the dressing of the cables the vendor supplies. The cal routine I used included ISOLN as required, however, both CH0 and CH1 ports are terminated with 50 ohm. So at UHF, if you average the noise in your head, about 70-75 dB DR. Despite getting consistent cals with the 2 track VNA (the white gecko) or antenna analyzer, I am not certain the convoluted cal routine of the 4 track or black VNA is IDENTICAL. I would think it would be, however, some peculiar cal results do occur. Incidentally, the black unit has a firmware boot message, GEN11.TAOBAO.COM. Is this the latest firmware? I am going to guess maybe not.
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Nano Vna Pre-Order?
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I pre-ordered my Nano-VNA from [bangood](https://www.banggood.com/NanoVNA-Vector-Network-Analyzer-50KHz-900MHz-Digital-Display-Touch-Screen-Shortwave-MF-HF-VHF-UHF-Antenna-Analyzer-Standing-Wave-p-1471576.html) Is this a legit seller? If so does anyone have an idea on how long we will be waiting for the next batch of shipments?
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Is anyone interested in an extended back cover for the NanoVNA? I designed and printed a sample it has a 6mm deep "pocket" that is 71mm X 40mm. Should be big enough to double sided tape a bigger battery in it 1 2 3 Frank ka2fwc@...
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I was interested in the performance of the output signal. So at first I measured the output power: 10 MHz -12,13 dBm 50 MHz -12,57 dBm 100 MHz -13,21 dBm 200 MHz -14,85 dBm 300 MHz -7,92 dBm 400 MHz -8,07 dBm 500 MHz -8,25 dBm 600 MHz -8,90 dBm 700 MHz -8,57 dBm 800 MHz -8,76 dBm Frequency Offset: Set to 100 MHz measurement was 99,999 908 MHz which is an offset of 92 Hz. Excellent !!! Output Spectrum: Spectrum is fine up to 270 MHz with harmonics at least 20dB down However above this frequency there is a strong subharmonic or spurious 12dB higher than the wanted signal. See picture enclosed. I have no idea how this may influence our measurements. In the pictures some sent to the group I can not see negative results. This probably explains why output power is higer at 300MHz and above. Ernst
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Calibration of the 4 track nanoVNA
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Several discussions with my ham colleague Gary, N3GO and wrestling in a quite area, I believe I have ONE approach that works well and is consistent with proper results. The main items to note: Only TWO traces are present during the cal, LESS CONFUSION! The frequency selection I chose, start and stop, is just an example. The use of the RESET soft touch is crucial. And I should update message #83. I believe that RESET eliminates the BOGUS firmware process that takes you to the DONE soft key premature!! =================================================================== Calibration for 4 track nanoVNA (VNA) Some notes: If you can have on hand another 50 ohm termination and another female-female SMA adapter, it is helpful. Supplied and used are the TWO- matched cables, the LOADS and one SMA adapter. Each of the NUMBERED items below represent your PRESS (SOFT KEY TOUCH). Turn on the VNA and note register 0 is ON. CONNECT THE EQUAL LENGTH MALE-to-MALE COAX CABLES TO CH0 AND CH1. 1. DISPLAY 2. TRACE 0 3. SINGLE 4. TRACE 1 Now we are displaying S11 and S22 ONLY both as LOGMAG. 5. STIMULUS 6. START 100 KHZ 7. STOP 500 MHZ 8. BACK 9. CAL 10.RESET 11.CALIBRATE Note! None of the softkeys on the right side touch screen are highlighted. Place an OPEN on end of CH0 cable and this will be followed by a SHORT. 12.OPEN 13.SHORT Place a 50 ohm LOAD(s) on the end of cables for CH0 and CH1. 14.LOAD 15.ISOLN Connect the 2-cables together using the female-female SMA adapter. 16.THRU 17.DONE Finally save to a desired register. That's it. Check and be sure that the open, short and 50 ohm are on the proper side of the chart. Note, the cables are CONNECTED to CH0 and CH1 and the calibration is to the end of the cables. The reference plane for insertion loss measure magnitude is in place of the adapter. However, the phase is subject to error and that needs addressed in another message. Also, with a thru cable connection between CH0 and CH1, the loss measure, S21 should be nearly 0 dB. Alan W4AMV
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I started looking at some narrow band mechanical filters. The measurement was challenged to look at a 500 Hz wide 455 kHz filter. I will double check if the limits are 101 data points/interpolation or simply LO jitter. It was very difficult to discern the transition skirt band. However, other somewhat wider mechanical filters worked out well as shown here. A 88 kHz sideband filter and a classic 455 kHz filter from a Collins. These were both headed to the land fill. Such a shame. Here old meets new! Alan
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Decided to test this SRH805S wide band antenna. They claim it covers 144/430/1200 MHz. While the nano doesn't cover 1200 MHz, it does handle the lower two bands. Clearly there is a problem as 144 MHz band is not showing any reasonable SWR. By the way, my graph shows the SWR (left scale in red) and reflected power in percent (right scale in green). As for the SRH805S, I must have gotten a bad one. One band missing!
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Shown here is measurement of 27 MHz crystal without any padding. It was done primarily to see if there would be any effect of calibrating Nano over small frequency range. Here I chose a center freq of 27 MHz, a span of 100 KHz and calibrated over that span. This gives about 1 KHz/point since Nano always captures 101 points. Both plots below are over this span. S21 (mag/phase) plot seems quite normal with no calibration artifacts. Z (mag/phase) was obtained for crystal with output shorted to ground (S11). As seen, the impedance nicely goes to about 12 ohms at the resonant point. So, it appears that Nano can be calibrated for small increments, at least as small as 1KHz.
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Improved measurement accuracy?
If you wanted to improve the measurement accuracy as you approach 900 MHz, then adapter removal is required. The current 2 cable connection for S11 and S21 cal and measure does not provide that ability. I suppose one could use the electrical delay to accomodate the inserted SMA adapter to move the measurement plane to the proper connector edge. Another approach going forward would not require adapter removal. The 2- cables provided with the 4 track VNA would have a female and male SMA at one end. Then no adapter is required. The DUT would now be directly insertable. For more information on this, search adapter removal VNA. Alan W4AMV
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I have been hacking my Gecko unit to add shields and I also decided to add an SD card slot I removed from an old Blackberry cellphone. As I mentioned in a previous post, old 2-way radios and cellphones have a treasure trove of re-usable parts. The first photo shows a pile of shields from several old Motorola HT1250 portables. Cellphone shields are similar. I got the TF card slot from an old Blackberry. Use a heat gun to remove them as well as switches. TIP: Heat the opposite side of the PCB when removing parts to prevent heat damage. The second photo shows a closeup of the installed shields - big difference in noise levels! The third and fourth photos show the TF card slot where I had to scrape some ground plane solder mask for securing it. In the upper left corner, you can see the push button I installed on the BOOT solder pads. I know the firmware doesn't support the SD card - yet - but that is what hacking is all about! Now, I'm waiting to receive the Black (Original design) version with the USB-C connector . BTW, that old Motorola cellphone battery lasts well over 4 hours.
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I made an enclosed case. I have to work on the switch opening.?? It looks pretty good. I have also designed a back that will hold a bigger battery. 1 2 4 4
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Electrical delay
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I do not see a specification for the units on electrical delay. I assume they are sec. Does anyone know what the handle is? You can enter numbers and play with the values until the swept display makes sense. For example, zero out a cable extension. However, it would be nice to know the units in advance if you have a precise extension in hand. Thanks, Alan
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Here is a complete case with the Sun Brim. I found 2 screws in my junk box Frank 1 2
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I just received my nano vna today, from Banggood. It was shipped without a battery. I was wondering what battery others were using. I did see some mention about a cell phone battery, but not model number of battery it was.
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I got prettty peed off with an eBay seller. I bought a NanoVNA, which he shipped 3 weeks after getting my money. It arrived yesterday, but when powered up, all I get is a white screen, and a couple of LEDs on. When powered off, one of the LEDs stays on for about 30 seconds or so. Anyway, I can't get anything out of this. The seller offered me a refund or a replacement. I said I would take a replacement if he could ship by DHL. FedEx or UPS, rather than their normal slow postal service. I suspect he is not actually going to use one of those couriers, but he has said express mail, so hopefully it wont be too long before I have a working one. -- 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
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Release notes from Google Drive Firmware folder translated and updated
Jul 05, 2019 1. nanoVNA_800 firmware addresses 300 and 600MHz peaks because si5351 is working at the limit. Jun 11, 2019 1. Fixed the problem that data retrieved by shell command (PC software) was incorrectly interpolated; 2. Passing (S21) calibration does not use source matching data (previously the original software used source matching data calibration always has errors, so it seems that there is no error, but it is not clear whether there will be other problems, please give me feedback after testing). May 07, 2019 The black frame at the bottom of the large font version is reduced, and the occlusion portion of the curved picture is reduced from 6 pixels to 2 pixels, reducing the influence on the use. May 05, 2019 A lot of feedback was received by Ham for antenna measurements, and a version optimized for antenna measurements was modified nanoVNA_900_AA This version is mainly modified to increase the font size from 5x7 to 7x13. At most, only 2 scan lines (trace) are allowed. The default trace 0 shows CH0 logmag, and trace 1 shows CH0 Smith. You can modify the port and type to be displayed as needed. If you measure the antenna, you can change the logmag to SWR. Since there are two traces less than the original, the saved data structure changes slightly. The nanoVNA_900_AA_20190505.dfu file uploaded this time has already cleared the user data. If you need to brush back to the normal version after saving the user data, you need to brush the nanoVNA_900_AA_20190505. Dfu clears the user data and then brushes the corresponding file. The software is free time to change, if you encounter any problems in use, you can communicate with me through Taobao shop gen111.taobao.com. I wish you all HAM, 55 happy! Apr 25, 2019 1. The impedance of the mark point on the Smith chart shows the value of the resistance zr, that is, the Resistance, and the anti-Reactance part is calculated to be the corresponding Capacitive or Inductive capacitance value or inductance value. If you need to check the complex impedance, the specific value of Impedance can be viewed using the host computer. If there is something wrong, you can contact me. 2. Optimize the driver of 900M firmware above 300M frequency si5351. Apr 24, 2019 To correct the problem of zr calculation error, the impedance of the mark point on the Smith chart is now displayed as the value of |Z|. Since the 900M firmware needs to dynamically adjust the power and gain during scanning, the command to manually set the power and gain under the shell is masked. Apr 17, 2019 Optimized scan gain nanoVNA_300_ch: 50K-300MHz, 5*7 Bitmap font, 4 tracks nanoVNA_900_ch: 50K-900MHz, 5*7 Bitmap font, 4 tracks(Default)
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got my nanovna today and after calibrating and doing all the settings the calibration is showing but i cannot get it to show any traces or readings in swr mode with 100 ohm load or when connected to an antenna on tx port ,it is the black version and has no screening near the ports on the pcb herbie gi6jpo
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The taobaoFOCUS site, can it be trusted?
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I found this as a site that helps you order from taobao in english. At least it could find Hugen's Nanovna item w/o any problems. Are there any serious gotchas in using this site?
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The Hugen shop at taobao, in English?
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I posted this a while ago about purchasing from taobao as a non chinese: I found a few things that were different to what I expected so maybe this will help: * You can enter your address before starting the purchase process. It is under your username then account. * Enter your address all on one line seperated by commas. If you hit enter after each line it will show a red error. * Use the standalone google translate page to translate your country name into Chinese Simplified. Then you can recognise the Chinese characters when you need to select it. * You need to click the image of the NanoVNA which then switches the price to 299, shown in the Red circle in Hugen's reply - the range in prices are for the various adapters pictured. Only one option is the VNA itself. * You need to select overseas in the option just above those little pictures too. Googles translate says "Shanghai to the country". Pick Overseas and then your country. * Google Chrome tries to translate by default, which breaks the "Buy" button so you need to turn off translate when you get to this point or use Firefox or something else. * Use the standalone google translate for the parts that don't make sense. Copy paste. wrote:
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