An apparatus and a system, as well as a method and article, may operate to transmit a first number of training symbols corresponding to a first number of communication chains to solicit a response including a second number of training symbols corresponding to a second number of communication chains. The main body is partially surrounded by a joining sleeve having chamber walls. Formed within the housing is an air pressure chamber which surrounds the atomizing barrel. Each pixel includes a source follower transistor that provides an output signal on a column output line for readout.