get a fix on sth

get/have a fix on sth AND get/have a handle on sth (get/have a clear determination or understanding of sth; to understand clearly what sth is like) — понять, разобраться; получить / иметь четкое представление о чем-л.

Example 1: Jill was finally able to get a fix on the situation.

Example 2: You need to make sure you’ve got a good fix on just how bad the problem is. (Mac.)

give a fix (provide a clear understanding)

Example 1: This report will give them a fix on the current situation.

The usages with fix and handle are colloquialisms dating from the 1920s; those with grasp are more formal and date from the late 1600s.

Related vocabulary:
get / have a grasp of sth
[good grasp of sth]
[get to grips with sth]
[get the feel of sth]
get the hang of it
come /get to grips with -> [get to grips with]