Abstract: A digital oscilloscope in which the acquisition/data accumulation is decoupled from the display of the accumulated data in order to increase the speed at which new data may be accumulated and displayed. The invention also provides for variable persistence in the accumulated data so that the displayed image shows the changes in the sampled event over time. The decay, however, is proportional to population for each amplitude/time combination in the data. This maintains the statistical integrity of the data. Further, the data from each channel is assigned a different color and different populations within the channel's data is assigned a different shade of the color. These shades are dynamically updated as data from new acquisitions are accumulated. In order to highlight the population distributions in the rare events, population saturation levels may be specified.

Abstract: A signal probe apparatus having a probe tip, a grounding attachment, a main body portion and a connector for use with a signal measuring device. The probe tip and the grounding attachment are coupled by way of first and second signal lines to the connector for supplying signals therefrom to the signal measuring device. A plurality of circuit elements, such as resistors, are connected between the second signal line and a third line in the connector; and switch means located on the main body portion enables a predetermined circuit value, for example, the resistance between the second and third lines, to be selectively changed to a respective value which corresponds to a respective one of several predetermined functions which may be performed by the signal measuring device. The selected circuit value is detected by the signal measuring device and the corresponding function is thereafter implemented.