Abstract: A method of preparing samples for testing, such as blood samples for photometric testing. A small quantity of the material to be tested, such as blood, is drawn into a capillary tube. The tube is then placed in a centrifuge and subjected to the action of centrifugal force which separates the test substance within the tube into a heavier component at one end of the tube and a lighter component at the other end. A second capillary tube, having an external diameter slightly less than the internal diameter of the first tube, is then introduced into the first tube and, by capillary action, picks up a definite measured quantity of the desired component from the first tube. The second tube, with the measured quantity of desired component therein, is placed in a cuvet previously provided with a predetermined quantity of a desired reagent liquid, and the cuvet is then shaken to disperse the contents of the second capillary tube into the reagent liquid in the cuvet.

Abstract: A zero-balancing arrangement incorporated into a pocket-type apparatus, which pocket-type apparatus is capable of being handled and operated by one hand of the user. The apparatus includes at least one battery to supply energy to a lamp which is used as a light source. A cuvet containing a liquid to be measured is placed into the path of a measuring light beam through an opening in the casing of the apparatus. A wedge-shaped filter is movable in the path of a second light beam by manual operation of a setting wheel. A measuring scale provided on the setting wheel can be inspected through a viewing window and the setting wheel can be adjustable relative to a mark fixedly located on the casing of the light beam paths provided in the apparatus, the first one travels through the liquid in the cuvet to a first photoelectric sensing device and the second light beam path travels unobstructed to a second photoelectric light sensing device.

Abstract: An automatic telephone answering apparatus having an announcement mechanism for playing an announcement message to a caller in response to a signal being received from the public telephone network indicating that the caller wishes to call the number to which the automatic telephone answering device is connected. The automatic telephone answering device has a housing containing circuitry for controlling the announcement text. The housing also has an empty space to receive a hand-operated dictating machine, which dictating machine has a tape mechanism therein for recording a message from the caller. Circuits are provided for controlling and sequencing the operation of the announcement text and the time period during which the caller can record information on the tape in the dictating machine.

Abstract: A sound recording and reproducing apparatus utilizing replaceable magnetic tape cassettes. The sound recording and reproducing apparatus includes an arrangement for the detection of a specified position of the tape utilizing a light detection unit which is installed in the apparatus. The light detection unit consists of a light emitting device together with a light receiving device. The casing of the cassette includes a reflective portion thereon which is placed in reflective alignment between the light emitting device and the light receiving device. Light can only be transmitted between the light emitting device and the light receiving device once a specified position of the tape is achieved.

Abstract: A cuvet is prepared for test analysis of a substance by placing a predetermined volume of a reagent liquid in a cuvet and then using a pipette or capillary tube for taking up a predetermined volume of the test substance by capillary action. Then the charged capillary tube is placed in the cuvet in the reagent liquid to permit the test substance to flow into the reagent liquid, and the substance is mixed with the reagent liquid in the cuvet so that the substance has a precise and predetermined ratio to the reagent liquid for speedily and accurately preparing the cuvet for a test analysis. A convenient kit is provided, containing a plurality of cuvets already charged with a measured quantity of a reagent liquid, and a plurality of capillary pipettes for use in adding measured quantities of some other liquid (e.g., blood) to the reagent liquid in a cuvet.

Abstract: A control device for an exposure factor of a photographic camera, such as the factor of shutter time or speed. A settable scale, settable to various values to control the exposure factor, is graduated logarithmically, and movement of the scale causes relative movement between a wiper or slider and a resistance serving as a potentiometer, the resistance of the potentiometer varying in a linear manner rather than logarithmically. The output of the potentiometer is connected to the input of a logarithmizer, the output of which is connected to a control element for controlling the exposure factor, the control being through an operational amplifier serving as an integrator, and through a threshold switch. An RC member associated with the amplifier is short circuited when the shutter is in its rest or closed position, the short circuit being interrupted at the beginning of the opening movement of the shutter.