First thing to say is there's a huge amount of tips to be found ,reading through the posts on this Forum. Many from the Nexus Designer & builder Georgi, who has posted often.
My tips are these.
Ground Balance until the sound is the same when raising or lowering the Coil. Then reduce Threshold to very quiet or silent, as you prefer.
Set the Sensitivity to zero, especially if the ground is wet. The Coils are very sensitive.
Set the Discrim to about 10:00 o'clock.
Use all Metal , single Tone. ( when you're used to the Machine, Iron targets will give a noticeably harsher Tone, while good targets will give a smoother, more 'rounded' Tone.
Note, that as with all Detectors, Large Iron can give a non Ferrous signal. The giveaway is that it's a full scale reading that still sounds off loudly when you raise the Coil up a foot or more.
If you get a consistent red that goes less than fullscale, it's always a worthwhile target.
Some small Copper Coins , eg. small Romans, will give a red one way and a blue the other. This will be consistent though, so worth the dig.............
It will take time to get used to the Machine, but it is really worth it, I can assure you. HH, Tim.
If it's Plough land, I use a high frequency machine with a faster recovery, as the targets are usually quite shallow, and there's always a lot of Iron about.
The Nexus Detectors are single minded machines, designed to find the deepest targets, and this they do, better than just about any Detector on the market. Cheers, Tim.