To provide an automatic correction device for switch error accompanied with range switching that can make an error of an amplification factor that a range switching device provided in a measuring instrument has in every range, to be almost zero.
This device automatically corrects an error of an amplification factor that range switching devices 4 and 5 of an acoustic measuring instrument 1 has in every range. It is provided with a reference signal oscillator 2 for generate a reference signal, correction quantity calculation means 6 and 9 that calculate a correction quantity by using the reference signal issued from the reference signal oscillator 2, according to an error of an amplification factor in every range of the range switching devices 4 and 5, a correction quantity holding memory that corresponds the correction quantity calculated by the means 6 and 9 with every range and stores it, and correction processing means 6 and 9 that read from the memory 8 the correction quantity corresponding with the range of the range switching device selected during actual measuring and add it to a measured value.
OYA MASAHARU
TAKEDA NOBUHIKO
KOBAYASHI KAZUYOSHI
