Philips PM3219/01 Notice D'emploi page 43

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4.2.1.
4.2.2.
4.2.3.
4.2.3.1.
4.2.4.
As the following procedure is identical for channels A and B only the procedure of channel A is described.
— Switch-on the oscilloscope with POWER S37 and check that the POWER indicator lights up.
— Set the INTENS control R17 and FOCUS contro! R16 to mid position.
Trace rotation
— Set the trace in the centre of the screen using the POSITION control R2.
— Check that the trace lies in parallel with the horizontal graticule lines; if necessary readjust the TRACE ROT
preset R15.
Use of probes
The 10:1 passive probes must be properly compensated before use, to avoid pulse distortion or amplitude
errors at high frequencies. For correct adjustment refer to chapter 1.4.
Vertical channels
— Connect the CAL output X1 to the channel A input X2 via the 10:1 passive probe (PM 8927).
— If necessary, compensate the probe. Refer to chapter 1.4.
— Check that the amplitude of the square-wave is 6 divisions on the screen.
Channel B only:
- Pull the POSITION control and check that the "PULL TO INVERT" switch inverts the signal.
- Push the control to its normal position.
— Release pushbutton AC/DC of the input coupling switch S26 to DC position.
— Check that the displayed signal shifts upwards because of the d.c. component.
— Depress the AC position again.
Vertical display mode switches
— Depress the ALT pushbutton S2b.
— Set the MTB TIME/DIV switch to 50 ms/div.
— Check that channel! A and B are alternately displayed.
— Depress the CHOP pushbutton S2C.
— Check that the channels A and B are simultaneously displayed.
— Set the TIME/DIV switch $23 to 0.2 ms/div.
— Apply the CAL output signal to both channel A and B inputs via two 10:1 probes (PM 8927).
— Set the AMPL/DIV controls of channel A and B to 50 mV/div.
— Set the signals from channels A and B in the vertical centre of the screen so that they completely overlap
each other. :
— Depress the ADD pushbutton.
— Check that the trace height is 4,8 divisions (A+B).
— Check that the POSITION controls of channels A and B influence the position of the added signal.
— Invert channel B by pulling "PULL TO INVERT" and check that a zero line is displayed.
— Check that by operating the POSITION controls a squarewave appears.
Time-base and triggering
-~ Set the controls as indicated in Section 4.2.
— Depress the DC pushbutton of the DTB trigger coupling switches.
— Pull the SLOPE switch of the MTB and check that the MTB is triggered on the negative-going slope of the
input signal.
:
,
~— Depress the SLOPE switch of the MTB to return to positive triggering.
— Set the MTB TIME/DIV switch to 0.5 ms/div.
— Pull the X MAGN switch combined with the X POS control and check that the horizontal deflection is
magnified by a factor of 10.
— Depress the X MAGN switch to its normal: position.
— Set the MTB TIME/DIV switch to 0.2 ms/div.
— Set the channel A AMPL/DIV switch to 50 mV/DIV.
— Set the DTB TIME/DIV switch to 50 ps/DIV and its continuous control to the CAL position.
— Set the DELAY TIME control to 0.
— Set the start of the sweep at the zero line of the first division.