This disclosure relates to a range extender having a through transmission path, a voice transmission path including a repeater, a relay for transferring back and forth between paths and a dual mode, loop current detector. In the idle state, the current detector is in a ''''slow'''' mode for the purpose of preventing (spurious) operation of the detector, except in response to an off-hook current flow. The transfer relay connects the repeater to the loop immediately after an off-hook is detected and the current detector is switched to its ''''fast'''' mode in preparation for dialing pulsing. The repeater normally remains connected to the loop for the duration of the call, even over dial pulsing. Dial pulsing is therefore repeated via the repeater, and not shunt aided. The dial pulses are detected by the fast current detector and the office loop is opened and closed through the repeater, which, from the office side, looks like a low resistance (1K) to low frequencies.