Can passive devices cause distortion?
Yes, absolutely! Distortion in passive devices, also known as passive intermodulation, is a very real problem. At some level all components generate distortion. Significant distortions can be caused by RF connectors because they may have dissimilar metals or dirt and oxidation at their contacts, ferrite devices such as splitters and couplers, relays, attenuators, PIN diodes, carbon resistors, and even coaxial cable with an impure dielectric. The main problem is usually due to the center conductor, not the ground. You can minimize passive intermodulation by using the same metal for all conductors that make mechanical contact to each other.
