Abstract: A splitter/combiner configured to split and combine Plain Old Telephone Service (POTS) signals and data service signals. The splitter/combiner comprises a line terminal configured to receive wires of a local loop connection to a Central Office of a communications network; a phone terminal configured to connect to telephone equipment at a customer premise; a data terminal configured to connect to a modem at a customer premise; a POTS line low pass filter connected between the line terminal and the phone terminal, the POTS line low pass filter configured to attenuate frequencies above 25 kHz and including a POTS line side transformer; a surge arrestor connected between the POTS line side transformer and the phone terminal; and a data line transformer configured as a differential mode choke connected between the line terminal and the data terminal.