22. Analog-To-Digital Converter Adjustments
A N A L O G - T O - D I G I T A L C O N V E R T E R
( B e n e a t h C o v e r )
4 .
Procedure without using Low-Noise DC Supply:
T P 4 T P 5
Figure 3-101.
Location of Analog-lb-Digital Converter Adjustments
a.
b.
C.
d.
e.
f.
h.
i.
k.
Press
Key in TRACE A
and SWEEP
Disconnect cable 0 (black) from sweep ramp input
Short
to
or connect SMB snap-on short to
Connect DVM to
and ground to
Set DVM
for V ac.
Adjust
OFFS until the level at
is at a
maximum ac voltage as indicated by the DVM (approximately
2.0 V ac). See Figure 3-101 for location of adjustment.
Remove short from
and
Reconnect cable 0
(black) to
Press
Connect DVM to
and ground to
Set DVM
for V dc.
Press SWEEP
Note DVM reading at end of the sweep.
The voltage will begin to drift immediately after the sweep
ends. Therefore, the first indication after the sweep ends is the
valid indication. It may be helpful to press
several times
to ensure a valid indication at the end of the sweep.
If DVM indication is + 10.020
V dc at the end of the
sweep, no further adjustment is necessary. Otherwise, adjust
GAIN and repeat step until the voltage at the end of
the sweep is + 10.020
V dc.
Adjustments
