| 摘要 |
<p>A digital oscilloscope comprises a circuit for detecting inaccurate reconstructions of waveforms. The fundamental frequency of the input signal under test of the oscilloscope is determined by a frequency determining circuit (20,50) and compared with the sampling frequency. If the fundamental frequency is larger than a predetermined fraction of the sampling frequency, an alias flag signal is produced by a circuit (56) giving a warning to the user that inaccurate reconstruction of a waveform can occur. The sampling rate can be increased in response to the occurrence of the alias flag signal to ensure accurate reconstruction of the waveform on the display means of the oscilloscope. </p> |
