Abstract: A method and device performing the method for estimation of cell count, such as sperm cell count, is disclosed. The device may be a kit including a cartridge configured to hold fluid, such as seminal fluid, and an instrument configured to centrifuge the cartridge. The cartridge and instrument are configured such that, during operation or centrifugation, they are securely attached to each other. The cartridge has a component with a defined cross-sectional volume. The defined cross-sectional volume is used to mark the component with markings, allowing a user of the device to read the markings and estimate cell volume and, thus, concentration. Various embodiments of the device are disclosed.

Abstract: In a control arrangement for driving a stepping motor through a digital frequency smoothing circuit, means are provided to supply the first input pulse to the smoothing circuit directly to the output circuit and to suppress the last output pulse from the frequency smoother to thereby obtain the advantages of frequency smoothing while at the same time speeding up the response of the system.

Abstract: In a control for a stepping motor which is stepped using a timing pulse generator and includes an on-off regulator means are provided to greatly reduce the average power loss of the motor when at a standstill by lowering the winding current from its nominal value to a substantially lower holding value when the motor is stopped.