Horizontal Deflection; Delayed Timebase Jitte R - Fluke PM3082 Service Manual

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6.3.28 Horizontal deflection; delay time multiplier
In this test the minimum and maximum delay time is checked.
test equipment:
None
settings/procedure and requirements:
1 - Press the AUTOSET key.
2 - Press the DTB menu key: select in the belonging menu DEL'D TB 'on' and MAIN TB 'on'.
3 - Set MTB to 0.5 ps.
4 - Set DTB to 50 ns.
5 - Adjust the vertical position of the MTB display with the CH1 POS control in the top half of the
viewing area.
6 - Adjust the vertical position of the DTB display with the TRACE SEPARATION keys (or the
TRACK control).
7 - Adjust the delay time to 500.0 ns by means of the DELAY control.
8 - Adjust the start of the MTB display exactly on the first graticule line by means of X POS.
9 - Verify that the difference between start of MTB and start of intensified part is between 0.9... 1.1
divisions.
10 - Adjust the delay time to 5.000 ps with the DELAY control.
11 - Verify that the difference between start of MTB and start of the intensified part is between 9.9
to 10.1 divisions.
6.3.29 Horizontal deflection; delayed timebase jitter
There is a certain instability in the starting point, the so called jitter, of the DTB. The maximum allowed
jitter is checked in this test.
test equipment:
Fluke 5500A mode: levsine (Alternative: function generator PM5136)
test set-up:
5500A
settings/procedure:
1 - Apply a 1 MHz sine-wave signal of 120 mV (pp into 50Q) to input CH1.
2 - Press the AUTOSET key and set for a trace-height of 6 divisions.
3 - Use a 50Q termination. For instruments with switchable 50Q input impedance it is
recommended to make use of this feature.
4 - Press menukey DTB and select in the belonging menu DEL'D TB 'on' and MAIN TB 'on'.
5 - Set MTB to 0.5 ms.
6 - Set DTB to 0.5 ps.
7 - Adjust the delay time to 0 s by means of the DELAY control.
OSCILLOSCOPE UNDER TEST
5 0 0 CABLE
PERFORMANCE TEST