Loom weft feed

To change the outer dimensions of the yarn feedwheel (101) in the yarn feed to a textile machine, such as a measured length of weft for a loom where different feedwheel sizes are required for different yarn qualities, control signals (15) for separate adjustment units (107) are generated by a control system as affected by starting the function of the textile machine or weaving, a weft yarn change, a pressure change in the jet of a jet loom, and the like. The adjustment (107) positions the feedwheel surface or surface component (103) through the signal to develop a new circumference size for the yarn carrier (104) of the yarn supply (105), according to the signal value or the number of signals. The carrier (104) is fitted with the separators (103c) to keep the wound yarn coils apart are held as projections at whatever size of the circumference of the carrier (104) and during any adjustment movements.