Abstract: The receiver can e.g. be designed as a pager by means of which information subject to charge can be received. In a receiver control unit (2) the information to be processed and displayed is filtered. The information to be processed is selected by means of an input unit (5). For determining the charges of the selected information a charge counter 6 is arranged in the receiver. If these charges reach a certain limit, the selection of further information is disabled. If the limit is exceeded, the processing of information subject to charge is stopped. In this way the user can, within his credit limit, choose himself which information or services he wants to receive without having to contact the service provider or network operator. The credit limit can be modified upon demand.

Abstract: Method and apparatus for synchronizing radio transmitters in a paging network. A synchronization order of base stations is determined based in part upon the relative geographic locations of the stations, and is communicated to the base stations via a command signal transmitted by the paging network unit. A predetermined first base station transmits a synchronization signal to base stations to be synchronized. Subsequent sequences of synchronization signals may be transmitted from synchronized base stations until all base stations have been synchronized. The synchronization signals may be transmitted via radio waves, and the synchronization order is determined so as to minimize the number of synchronization sequences and maximize the number of base stations synchronized simultaneously in parallel. Transmitted synchronization signals are corrected to compensate for propagation delays caused by the distance between base stations and for delays which occur within an individual transceiver.

Abstract: In order to adjust the frequency of an oscillator in a substation of a network to a reference frequency of the network, a reference station is provided with a high precision oscillator which is connected to a clock input of a counter. If this counter has a defined counting state, a start signal is generated and transmitted to said substation. At another defined counting state a stop signal is generated and transmitted to said substation. In the substation the oscillator to be adjusted is connected to a local counter, which counts the pulses of the oscillator between said start and stop signals. The count of this counter then is used as a measure for the frequency deviation of the oscillator and can be used for generating a control signal to adjust the frequency of the oscillator of the substation.