A ladder drum for adjusting and regulating the angular orientation and closure of horizontal slats of a venetian blind, of the type incorporating ladder cords or tape ladders, having a polygonal profiled structure comprising a series of planar sidewalls defining a substantially hollow interior. The splint is provided with a contact portion for contacting opposed forward teeth to the forward teeth to which the splint is attached such that movement of the opposed forward teeth with respect to the contact portion maintains the spacing of the rearward teeth. A rectifier module is coupled with the secondary winding and configured to rectify the signal induced at the secondary winding. The substitution response functional unit 24 simulates message transmission between the home network and each of substitution response modules, and message transmission between each of substitution response modules by said network simulation module. An actuator is moved by the handle and has a lock position contact portion and an open position contact portion.