Abstract: Disclosed is an underwater seismic exploration system utilizing a sonobuoy for the radio telemetry of seismic data signals to a remotely located receiver, the sonobuoy including circuitry for digitizing the analog signals generated by hydrophones suspended from the sonobuoy prior to the application of these signals to an RF antenna. The remotely located receiver includes an antenna for receiving the transmitted modulated digital signal information, and means for demodulating, demultiplexing, and appropriately converting the signals for either analog or digital recording of the received data.