Abstract: A printed circuit board upon which are mounted a number of electronic components is provided with a connector strip for electrically coupling the components to respective components on a second circuit board located underneath. The strip comprises a body portion and pins projecting thereform. The pins have a stepwise configuration with a first end portion extending through apertures in the upper circuit board and connected to a second connector strip on the second circuit board, a second end portion extending through the body portion, and a middle portion which abuts the surface of the upper circuit board and by which the strip is connected to the upper circuit board by means of a solder joint. Components on the upper circuit board are electrically coupled by means of tracks which are connected to the components at one end by a solder joint and at the other end by a solder joint, via pins, to the second connector strip and tracks on the lower circuit board.

Abstract: An I/O unit has a fixed unit such as a housing provided with a multiplicity of connection terminals and an LED display module unit. A mounting/dismounting unit is provided with a terminal block including connection terminals to be coupled with the connection terminals of the fixed unit. The mounting/dismounting unit has a hinge disposed at an end thereof and the fixed unit has a pin and a grip capable of being engaged with the hinge. The grip is pulled out to a position to be used and then further pulled out, whereby the mounting/dismounting unit is forced out, drawing an arc about the pin and separated from the fixed unit. With this arrangement, an I/O module with a mounting/dismounting unit capable of being easily removed is provided.