Kikushi Model 677A Wow & Flutter Meter is designed to measure variations in the running speed of various sound record/playback devices such as audio tape recorders, video tape recorders, disc record players, and cine sound recorders. Measurement can be made also in conformity with the JIS Standard, NAB Standard, and CCIR (DIN) Standard. The measuring sensitivity is very high and covers a range of 0.005 - Vfo being divided into three sub-ranges. Measurement can be made under the weighted mode as per the JIS, NAB, or CCIR (DIN) Standards, under the state that wow and flutter are mutually separated, and under the state that wow and flutter are mutually superimposed. The tape speed is digitally measured with a frequency counter and is indicated with a 4-digit readout. Due to the above features, the 677A is very convenient for research, development, manufacturing, inspection, and maintenance of record/playback devices. The 677A has output terminals for an oscilloscope and a recorder in order to facilitate analysis of wow and flutter by displaying or recording the waveform on such instruments.