3.10.3 Summary of Techniques for Coherent Noise Reduction
The practice of the art and science of coherent noise reduction should begin with the elimination of local noise sources. Obviously,
these are noise sources which have been identified and which can be controlled.
These sources might include digital and computer equipment operating in the same immediate environment,
or interference caused by sparking motor commutators, etc.
The offending noise sources must be enclosed in appropriate, grounded, electrostatic shields.
Their power leads must be low-pass filtered or bypassed as they leave the shield—the use of ferrite beads and feed through capacitors may be indicated.
In addition, power leads should be twisted so that minimum magnetic field is created.