Abstract: An active flowchart label is provided for displaying information regarding the state of an instrument. A label is provided having transmissive regions positioned within a graphical representation of a circuit path or in relation to textual messages provided on the label. Light sources within the instrument are positioned to illuminate the transmissive regions when activated to communicate which circuit paths are active. Additional light sources within the instrument are positioned to illuminate transmissive regions associated with the textual messages to provide additional information regarding the operation of the instrument. Light channels may be provided to direct the light from the light sources to the transmissive regions.

Abstract: An apparatus for measuring Output Voltage characteristics on a dynamic logic signal at an output of a device under test (DUT) includes a comparator for comparing the voltage at the output with a threshold voltage to generate a control signal. The control signal is used to switch an appropriate current load to the output in response to the dynamic logic signal. A measurement of the voltage at the output provides the Output Voltage characteristics without requiring control of an input stimulus or a static logic level at the output.

Abstract: Apparatus for the inspection of the end surface of a cylindrical object including a device for irradiating the end surface of the object, a detector for detecting radiation reflected by the end surface substantially parallel to the axis of the object and a calculator for calculating the proportion of the end surface which has reflected radiation directly to the detector device, wherein the means for irradiating comprises a ring source the center of the ring being substantially co-incident with the axis of the object and being substantially transparent to reflected radiation so that light reflected to the detector passes unhindered through the ring, the ring source having associated therewith a device permitting substantially uniform irradiation across the said end surface.