Abstract: Telecommunications systems are often built by interconnecting similar subsystems, to enable the adaptation of the systems to different numbers of subscribers. Such a structure must fulfill the requirement that a subscriber with a cordless terminal can move freely within the area served by the telecommunications system without interrupting the call, regardless of which subsystem serves his radio cell at the moment. An uninterrupted hand-off requires the digital information to be frame synchronized. By measuring the time difference (.DELTA.t2) between the frame synchronization pulse (FR1) of a subsystem and the frame synchronization pulse (RFR2) which is recovered by an adjacent subsystem, a delay time interval can be calculated, taking the signal propagation time (.DELTA.T) between the subsystems into account, so that any frame offset is equalized. The method can be used for systems which operate according to the DECT standard.