To Test Time Measurement Accuracy - HP 54520 Series Service Manual

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To test time measurement accuracy
To test time measurement accuracy
This test uses a precise frequency source to check the accuracy of time measurement
functions.
Specification Delta-t accuracy
Repetitive (28 averages) +[(0.005% x delta-t) + (0.1% of full scale)+ 100 ps]
Real Time * +/(0.005% x delta-t) + (0.2 x sample period)]
* The specification applies to bandwidth limited signals (tr = 1.4 x sample period). The
sample period is defined as 1/(sample rate). The specification also applies to those automatic
measurements computing time intervals on identical slope edges (like pos-pos, neg-neg).
Equipment Required
Equipment Critical Specifications Recommended
Model/Part
Signal Generator 1-40 MHz, HP 8656B Opt. 001
timebase accuracy - 0.25 ppm
Pulse generator tr from 1.0 to 2.8 ns, 280 mVp-p,,externally HP 8161A
triggerable
Cable Type-N 24 inch HP 11500B
Cable BNC HP 10503A
Adapter Type N (f) to BNC (m) HP 1250-0077
Repetitive Mode Procedure
This test checks time measurement in repetitive mode with averaging.
Set the HP 8656B signal generator to 40 MHz (25.0 ns period) and 800 mVrms.
Connect the output of the signal generator to the EXT INPUT of the HP 8161A pulse
generator.
Connect the output of the pulse generator to the channel | input.
Set up the pulse generator.
Input Mode = TRIG
Ext Input = 50 ohm, Trig Level = centered
Delay = 0s
Width = 12.5 ns
Leading Edge = 1.3 ns
Trailing Edge = 1.3 ns
High Level = 0.14 V
Low Level = -0.14 V
Press Recall ,thenpress cir to set the oscilloscope to default conditions.
Press the channel 1 key (bottom row). Use the impedance soft key to select 50Q pe.
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