Spurious coupling mechanisms
Spurious coupling refers to some mechanism producing an unwanted voltage or current that interferes with a signal. Spurious voltages or currents can enter an electronic system by several different ways. Because the respective prevention methods differ, it is essential before attempting remedial action to identify which mechanism is involved. The primary interference mechanisms and prevention methods are:
1. Direct conduction (prevention: eliminate spurious conductive path)
2. Capacitive coupling (prevention: electrostatic shielding)
3. Inductive coupling: (prevention: use coax or twisted pair)
4. Pickup of radiated electromagnetic field (prevention: electrostatic shielding and coax or twisted pair)
5. Ground loops (prevention: identify and eliminate)