An improved modular telephone-style jack featuring a guidance system positioned on the lower outer wall so that the guidance system maintains the position of the surface mount solder tails of the contacts of the jack in a controlled fashion. The block assembly includes a block comprising a front wall, a left side part and a right side part. During a transition interval, a relatively high frequency switching signal is used to lower the capacitance and increase efficiency. The sensor is adapted to sense a changed condition from a required parameter external to the housing, e.