We have all had cause to deal with those cheap SMA(F)-SMA(F) adapters that do not have means to securely grip the body of the adapter to remove a properly torqued connector nut. These are commonly the type included in NanoVNA kits.
Above is a demonstration of my solution:
- a loose SMA nut has been cut longitudinally with a jeweller’s saw and the burs removed;
- the modified nut is threaded FULLY onto the adapter;
- the modified nut is gripped tightly with pliers to grip the adapter without damaging the threads;
- The cable nut is loosened using an 8mm wrench.
Above is a close up pic of the modified nut.
Avoidance is better
Don’t use adapters that do not have a means of securely gripping the body. Discard those you have to avoid accidentally using them. If you are going to discard the adapter, simply use a pair of pliers on the thread.
Adapters are available with flats in the middle, typically 5.5mm AF.
Here is an example:
Above, note the longer adapter with the flats in the middle. Be very careful to not accidently choose reverse polarity (RP) products.
Adapters are also available with a knurled section in the middle, you need to use pliers on them at the necessary torque.