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Hello, I recently purchased a nanovna s-a-a-2 (hardware version v2_2, 50k-30ghz, owocomm design), and after around 2 weeks of work the measurements on the s11 port decided to malfunction. At the time of the s11 port breaking a simple v dipole was connected to the s11 port of the analyzer, and the nanovna was plugged into a usb port on my computer, where i was getting my measurements from using vna_qt. After the malfunction I tried the following: 1) inspect my sma ports to make sure the little spring contacts weren't bent or out of place 2) connected all the different types of calibration loads directly to the s11 port with no change in any parameter 3) I connected a regular sma connector to both ports at once and observed the s21 logmag value change, which seems to imply that something is wrong with the s11 port only 4) disassembled the vna to check if there was some obviously blown up component (there arent any, even under the metal shielding) 5) cleared Please help diagnose and potentially fix this problem. I attached 3 pictures of the analyzer: one with no connections, one with the 50ohm load, and one with an sma connector connecting the 2 ports.

I recently replaced my MCU on my old NanoVNA H v.3.4 board. I was able to flash the latest Dislord firmware onto the MCU via DFU and it loads up. However, it is frozen on startup. No input on touch or jog wheel. I have replaced the MCU with another one I had to see if this made any difference - none. The jog wheel switch is working confirmed by continuity test along the VDD to pins 11, 12 and 13. I have tried downgrading to a more recent version but that doesn't work either. Any other suggestions of where I should look either on the board or in firmware to try to assess? I like this NanoVNA for sentimental reasons - I have used it since I was a Foundation call and have taken it everywhere with me portable ops.

*Now down to two HF antennas at new QTH at Crosslands Retirement Community (Kennett Square) SW of Philly* * * *Still have major high noise level from 1-10 MHz and working to solve it. * * * *1) NVIS horizontal end-fed 135 ft - tunes up easily on low end of 80m/40m/20m/ 17m/15m/10m* * SWR about 2.5:1 on 30m band, but I have a Hustler mobile antenna for 10 MHz band * *2) Vertical (made from old Cushcraft A10) 16 ft with home-made matching coil at base: covers 20/17/15 meters for low-angle DX with a few radials * *Both antennas doing well, catching signals from all over the world on the vertical.* *Horizontal wire is doing well on the NBEMS regional nets on 80m and 40m.* de k3eui barry

I've used my NanoVNA-H4 periodically for several years. Yesterday I charged it, then upgraded the firmware from NanoVNA-H4-SI_20211230 to NanoVNA-H4-SI_20211230. I re-calibrated and started doing some testing with it apparently working fine. I got distracted for a few minutes, and when I checked the screen was black. I powered it off, then back on, but the display only appeared for a second, then went black. Since then when I turn it on I see a normal display for approximately one second, then it apparently shuts off. Things I've tried, none of which have made any difference: * Charging it, including overnight. * Powering it on while plugged into a charger or USB port. * Disconnecting the battery for a while, then reconnecting it. * Powering it from USB with the battery disconnected. I wanted to try re-flashing old firmware, but it appears to do the same thing in DFU mode. When I power it on while holding the multifunction switch, I see the following in dmesg on Linux, and dfu-util doesn't see it: [385834.014786] usb 1-3.4: new full-speed USB device number 39 using xhci_hcd [385834.104077] usb 1-3.4: New USB device found, idVendor=0483, idProduct=df11, bcdDevice=22.00 [385834.104090] usb 1-3.4: New USB device strings: Mfr=1, Product=2, SerialNumber=3 [385834.104096] usb 1-3.4: Product: STM32 BOOTLOADER [385834.104101] usb 1-3.4: Manufacturer: STMicroelectronics [385834.104105] usb 1-3.4: SerialNumber: 205E33642031 [385835.056995] usb 1-3.4: USB disconnect, device number 39 Any suggestions of other things to try? Thanks, Jim

Hallo, I need help, I only need this instrument to measure the length of the cable and where the cable is open. If possible, I would measure rg6 and rg11 75ohm, the longest length up to 10-30m I have set everything, but I don't understand what values ??to type in the option STIMULUS FREQUENCY. Thanks everyone for your help