Hi Torbj?rn,
I have a comment about the photo.
It is not recommended to insert the HC-05 (or any other type) into the device. On the other hand, the preferred solution is to plug the required connection points into a socket and plug the module into this socket when you want to use it. The proximity of the wifi module can cause interference in the NanoVNA and you will see erroneous measurements.
Just a suggestion, the decision is yours.
73, Gyula HA3HZ
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