TB 9-6625-2274-40
Figure 2. Aberration waveform display.
(4) Perform Delta V measurement technique, using digitizing oscilloscope, by
placing one marker on the upper peak of the aberration and one marker on center graticule.
Digitizing oscilloscope Delta V (peak aberrations will indicate <3 percent of
amplitude recorded in 25 a (5) above.
(5) Adjust one Delta V marker of digitizing oscilloscope to the lower peak of the
aberration and one to center horizontal graticule.
(6) Digitizing oscilloscope Delta V (peak aberration) will indicate <3 percent of
amplitude recorded in 25 a (5) above.
(7) A d j u s t d i g i t i z i n g o s c i l l o s c o p e D e l t a V m a r k e r s t o t h e u p p e r a n d l o w e r
aberrations.
(8) Digitizing oscilloscope Delta V (peak-to-peak aberration) will indicate <4 percent
of amplitude recorded in 25 a (5) above.
(9) Maintain setup and continue with next performance check.
b. Adjustments
(1) Press OUTPUT ON pushbutton off and remove X10 attenuator. Connect
OUTPUT to digitizing oscilloscope INPUT/TDR OUTPUT using PULSE HEAD
and X5 attenuator.
(2) Press pushbuttons as listed in (a) through (g) below:
AMPLITUDE MODE AMPL MODE FAST EDGE.
(a)
AMPLITUDE MODE EDGE POLARITY .
(b)
AMPLITUDE MODE FREQ
to highlight l00 kHz.
(c)
VARIABLE ON off.
(d)
TRIGGER OUTPUT on.
(e)
TRIGGER NORM on.
(f)
OUTPUT ON on.
(g)
(3) Press and hold FAST EDGE pushbutton until display indicates dL.
(4) Set digitizing oscilloscope probe attenuation to 5 and acquire signal using
digitizing oscilloscope and set sensitivity to 10 mV/D and sweep speed to 5 ns/D.
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