Tektronix VM700T, Руководство пользователя

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Waveform Mode
3- 14
VM700T Option 01 (NTSC) & Option 11 (PAL) User Manual
Sine-wave frequencies can be easily measured with cursors. The following
procedure produces the best accuracy using asynchronous sampling and with
averaging on to reduce the noise.
To Measure a Sine-Wave Frequency. Expand the desired sine wave (for example,
color burst) so two cycles fill the majority of the screen.
Position the sine-wave zero crossings to occur at the horizontal reference line.
Select the Cursors soft key and position a zero crossing on the cursors.
Select Lock Left and move the waveform to the left one full cycle (two zero
crossings) and position the zero crossing on the right cursor. Select Lock Right.
The sine wave frequency is now displayed in the Frequency (1/T) readout.
Compare this value with the freq (MHz) = value in the first cursor status line
(third line from the bottom in the status area).
The Cursors mode provides a quick tool to make amplitude measurements and
indicates measurement results in the same units as the vertical scale, to three
decimal places. The following example discusses the Vertical delta readout and
its use in measuring amplitude of the color burst.
Cursor readout
Figure 3- 4: Color burst aligned with horizontal reference line
Using Cursors to
Measure Frequency
Using Cursors to
Measure Amplitude
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