An example apparatus includes a connection module. The example connection module includes a connection interface and a connection matrix having a root transmission line to conduct signals to and from the connection interface. The connection matrix also includes branch transmission lines that are connectable electrically to the root transmission line to conduct the signals to and from the root transmission line. Each of the branch transmission lines is part of an electrical pathway between a device and the root transmission line. A housing encloses the connection matrix and enables access to the connection interface. The root transmission line and the branch transmission lines are each multi-conductor transmission lines that conduct the signals in transverse electromagnetic (TEM) mode.