High-speed digital transmission can be achieved with existing phone lines and HDSL chipsets. Two original ISDN signals [4,5] at a rate of 160 kbps are multiplexed by a MICS card [6] of a signal provider [1]. The resulting digital signal is transported over a twisted cable pair [2] which has an approximate maximum length of 16 kft. At a receiving end, the signal is demultiplexed and regenerated by a subscriber's MICS card [7]. The subscriber's MICS card is line-powered via the cable [2] to avoid dependence upon local power. The regenerated signals are transmitted over two ISDN cables to remote premises which can be as far as 18 kft away.