A servicing cassette for an inkjet printhead includes wiper blades which may be manually or automatically switched when worn or having reached the end of their intended service life without the necessity of replacing the entire servicing cassette. Copper diffusion barrier films in accordance with the invention are composed of one or more layers of silicon carbide, at least one of the silicon carbide layers having a composition of at least 40% carbon, for example, between about 45 and 60% carbon. The wavefield space is the space spanned by the channel parameters that characterize the multipath fading environment.