PURPOSE: To transmit such a volume of information that can be identified and processed in a vague period by transmitting and detecting a larger amount of information than a combination capable of taking repeatedly r-piece of signal information out of n-piece of signal information.

CONSTITUTION: A pulse is inputted to a counter 1, and its output is outputted to either one of input terminals of respective gate circuits 2a∼2n, while a clock pulse CP is inputted to the remaining one of the input terminals of the gate circuits 2a∼2n. Accordingly, they take the AND of the output of the counter 1 and the clock pulse CP and output it to counters 3∼5. Their outputs are transmitted to an ROM 6, and the output conforming to nDr is delivered as the transmittable information volume from the ROM 6.