characteristic values required to realize an optimal production result these input data may be predetermined or modified both by the manufacturer of the quality control system and by the user of the quality control system this allows to achieve a far reaching adaptation of the process control to modified production procedures shown in fig2 is a typical arrangement for the production of a package of a synthetic fiber a yarn 23 is withdrawn by means of a godet arrangement 21 from an extrusion and spinning unit 20 and wound on an empty tube by means of a yarn traversing mechanism 27 in godet arrangement 21 the yarn receives by corresponding measures its desired physical properties such as tensile strength elasticity denier and others the yarn may be also advanced through texturing devices not shown so as to realize desired surface characteristics after this actual production and finishing of the yarn the latter is wound to a package in a takeup device shown in the lower portion of fig2 to this end the continuously withdrawn yarn 23 advances over an apex yarn guide 25 to a traversing mechanism 27 which reciprocates the yarn for winding initially over rotating empty tube 28 and thereafter on rotating package 29 a drive 30 necessary to rotate the yarn package is controlled via a control device 31 so that the circumferential speed on the package surface remains always constant the frequency of the yarn traversing mechanism is predetermined via a drive motor which is controlled by a control device 32 the adjustment between.