Abstract: A tufting machine having belt and pulley drive system for driving the yarn feed rolls and backing fabric feed rollers from the main shaft has rotational speed sensors for determining the rotational speed of the main shaft, the yarn feed rolls, the input shaft to the fabric feed rollers, and the front and rear fabric feed rollers. Each sensor emits a pulse whenever a tooth of a gear on the shaft passes so that a pulse train is generated. The pulse trains are transmitted through selector switch to a speed ratio indicator and to a digital tachometer. The speed ratio indicator displays the ratio of the selected signals so that representations of pile height, density, stitches per inch of backing fabric can be monitored.