The "Hole in the Bucket" Principle
The "hole in the bucket" principle refers to a leaky bucket
— all holes must be repaired before the bucket stops leaking. Similar to the
bucket, a network node may have more than one EMC problem. For example, a design
may have both inductive and capacitive coupling to a noise source. The engineer
tasked with producing a working design should be aware that multiple fixes may
have to be applied simultaneously to eliminate the problem(s), and that the fix
may be more than the sum of its parts; two fixes that show no effect when tried
separately may cure the problem when applied together. The best strategy is
often to produce a functioning unit by any means possible, and then begin a
process of subtraction to identify the minimum set of changes required