Abstract: The magnetic shield preferably encloses circuitry connected to equipment in a high magnetic field (e.g., two transformers of a gas flow transducer in an MRI suite). The magnetic shield is preferably oriented so that its long axis is aligned with the axis of maximum magnetic sensitivity of the enclosed circuitry. The shield shunts external magnetic flux around the enclosed circuitry to protect the circuitry from saturation in the high magnetic field. The shield is preferably made from hot rolled low carbon steel which has relatively low permeability and saturates slowly. The physical size and construction of the shield reduces magnetic flux within the shield with a minimal amount of iron. In another embodiment, a magnetic field sensor is mounted within the shield to measure the magnetic field affecting the enclosed circuitry. The sensor is coupled to an external circuit which indicates when the magnetic flux is strong enough to affect the operation of the enclosed circuitry.

Abstract: The magnetic shield preferably encloses circuitry connected to equipment in a high magnetic field (e.g., two transformers of a gas flow transducer in an MRI suite). The magnetic shield is preferably oriented so that its long axis is aligned with the axis of maximum magnetic sensitivity of the enclosed circuitry. The shield shunts external magnetic flux around the enclosed circuitry to protect the circuitry from saturation in the high magnetic field. The shield is preferably made from hot rolled low carbon steel which has relatively low permeability and saturates slowly. The physical size and construction of the shield reduces magnetic flux within the shield with a minimal amount of iron. In another embodiment, a magnetic field sensor is mounted within the shield to measure the magnetic field affecting the enclosed circuitry. The sensor is coupled to an external circuit which indicates when the magnetic flux is strong enough to affect the operation of the enclosed circuitry.

Abstract: Apparatus for thermal printing of a color image includes a donor member that contains a set of color stripes for each pixel in a repeating pattern in the cross-scan direction and in continuous stripes in the page scan direction. As the printing beam is scanned across the donor, it addresses the sequence of color dyes and if the beam is of sufficient intensity at any one of the color stripes; it causes the dye to transfer to the receiver material. To compensate for variations in the scan rate of the beam, light reflected from the donor member is used to form color timing signals that correspond to the color stripes of the pattern scanned by the beam. The timing signals align the modulation of the beam to the color stripe pattern of the donor member whereby accurate color registration is obtained.

Abstract: Apparatus for directly recording television signals on a magnetic medium strips out sync and blanking information. Low frequency components of the television signals are time compressed, i.e. frequency shifted, and recorded as a substitute for the stripped-out sync and blanking information. Thus, high frequency components of each video line are recorded, followed by that line's low frequency components, thereby facilitating the playback of low frequency information. In time compressing the low frequency information, the video signal content of a line is sampled at a predetermined rate. Each sample is then quantized for purposes of improving the playback signal-to-noise ratio, i.e. the effect of tape modulation, and other, noise is nullified by sample quantization. And, to cut the bit rate resulting from sample quantization, a preferred form of the invention groups the quantized bits and records analog representations of the bit groups.