Find the length of a coaxial cable with a NanoVNA-F V2
How to find the length of a piece of coaxial cable with your NanoVNA.
First you need to know the velocity factor of the cable.
Do not connect the cable to the NanoVNA at this time.
Setup
To activate the various menus, click on the right side of the VNA display and select the following values:
- STIMULUS / START / 100 k
- STIMULUS/ STOP / 50 M

- DISPLAY / TRACE / TRACE_0 (only)
- DISPLAY / FORMAT / MORE / LINEAR

- TDR / LOW PASS IMPULSE + TDR ON + VELOCITY FACTOR (0.83)

- MARKER / SELECT / ALL OFF + MARKER_1
- MARKER / SEARCH / TRACKING
- MARKER / SEARCH / MAXIMUM

Now you can connect the coaxial cable to the PORT_1 of your NanoVNA and the coaxial cable length is displayed as follow:
The above test was carried out with a length of a Messi & Paoloni ULTRAFLEX 7.3 mm cable.