Compact Designed Yarn Detector has the feature contact less sensing of yarn and hence no additional tension on yarn and has the feature of mechanical linkages and wear of moving parts as in electromechanical stop motion levers are eliminated. The Detector ensures trouble free operations over long periods, remains unaffected by dirt, yarn colours, yarn material and finish and has various optical sensors designed to suit different applications. The Detector has the control logic unit mounted in a convenient position and can be designed to suit specific requirements and is suitable for operating a wide range of devices including cutters, relays, solenoids, warning lamps, hooters etc. The Detector is designed to withstand vibrations and temperature ranging from -5 ° C to 50 ° C and has programmable sequence length/ production counter. The Detector has compact and rugged design. The Compact Designed Yarn Detector has the feature that detection can be achieved on all types of moving yarns such as traversing, ballooning or yarn moving in straight line and on detection appropriate control signal can be generated through allied circuitry to suit specific requirements.