Hologic DISCOVERY A, Техническое руководство

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Discovery QDR Series Technical Manual
1-14
1.3.8 Maximum Deviation
The maximum deviation from the preindication given by labeled technique factor control
settings or indicators are as follows:
1.3.9 Measurement Criteria for Technique Factors
The measurement criteria of the technique factors is as follows:
Peak Potential: +/- 15%
Current: +/- 40%
Time: +/- 10%
Peak Potential: The voltage peak is measured with an oscilloscope. Voltage is a squarewave pulse.
Peak is defined as the peak voltage of the 4 millisecond pulse, discounting any initial
overshoot.
Current: Current is measured with an oscilloscope on the last millisecond of the 4 millisecond
pulse.
Time: Time of each pulse is measured with an oscilloscope and defined as the time between
50% rise and fall times of the peak potential pulse. Time of the scan is measured by
counting the number of AC line pulses from the start to the end. X-ray pulses are
synchronous with the AC line.