Counting losses of multichannelized delay lines are calculated and a delayed coincidence spectrometer is designed. As the results of the calculation, 10 delay lines are prepared as a multichannelized delay line in the spectrometer. In order to set the delay times of 10 delay lines exactly the same, a digitally controlled system is employed. The experimental results of counting losses and delayed coincidence rates show good agreements with the calculated results. According to the investigation of the counting loss of the multichannelized spectrometer, it is noted that the counting efficiency of the 10 channelized spectrometer is about 400 times better than that of a single channel spectrometer.