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I have a RF choke in a TS-530S that I'm trying to test for induction and frequency. I saw the methodology of building a loop to go around a coil to read this. I really don't want to remove the choke, it's old and fragile. I made a partial loop, see image, and was able to get a frequency from it. I don't know anything about this, it was an experiment. Does anyone have a more educated idea about the test?

Hello guys, I'm new here and I'm having a hard time figuring out how to use my NanoVNA to measure those things. I made a search in the group topics but it's always about the results and I can't really find any simple tutorial on how to take those measurements. - About transformers I would like to measure the ratio but I don't really know where to plug my nanovna to do that and how to configure it. I have "three outputs" primary, common and secondary. Should I use the 2 ports of the nanoVna to try and obtain a result ? - for the inductors I would like to know if I can just plug to the 2 ends of it and find it's value ? which value should I show on my display ? - for the trap filter I used the method where you just go through the inductor with a cable and look at the phase but I'm not really sure it's the best way to do it, can I just plus to A and B on my graph and look at the result instead ? If you have any link or video that shows the detail of the measurement and wiring process I'd greatly appreciate that. As I said I'm a new ham so I don't really know how to use my VNA except for measuring SWR of my antenna but I'm convince it's a great tool, I just need to learn how to use it.

Using a VNA to measure dipole antenna feed point characteristics has been discussed. I believe this is a little different twist. I have an attic mounted 1/2 wave dipole antenna with a 20-25 ohm Z0 at the feed point. I expected this because of the 12 foot attic mounting height, non-linear non-symmetric shape, near by structures, poor ground effect, other constraints, etc. Having confirmed this, how to best match this dipole's Z0 of 25 Ohms to a 50 ohm coax line is now the challenge. Would a 1:2 UnUn be appropriate? 1:2 BalUn? If so, what would this UnUn / BalUn look like? I have seen 2:1 commercial units available. The input and output connectors are for 2:1. I have not seen one with the connections setup for 1:2. If this is a viable are there any recommended commercial sources for it? I would then use the VNA to verify results. Thoughts and suggestions? Thank you. Bill WA2WIO

Is it a viable method to do calibration of the VNA with a transmission line attached, so that when the DUT is attached to end of that line the measurements are true measurements of just the DUT?

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.