HP 54501A - HP 54501 A Self Calibration; Section 4. Adjustments; Introduction; Equipment Required

4-1 . INTRODUCTION
This section
provides adjustment and self
calibration
procedures for the HP 54501A .
The
assemblies with adjustments are :
the power
supply, CRT monitor,
and the systemboard .
Figures
4-1 and 4-2 are the testpoint and ad-
justment
locations for the HP 54501A
.
4-2 . EQUIPMENT
REQUIRED
Equipment required
for adjustments is listed in
the
Recommended Test Equipment table in
section
1
of
this manual . Any equipment
that
satisfies
the critical specification listed
in the
table may be substituted
for the recommended
model .
4-3 .
CALIBRATION INTERVAL
The
recommended calibration
interval for the
HP 54501A is 2000
hours of operation (or two
years, whichever
comes first) . The adjust-
ments are
set
at
the factory on assemblies
when they are
tested . However, adjustments
may be
necessary after repairs have been
made to
the instrument . Usually the only as-
sembly that may require
adjustments is the as-
sembly that has
been replaced .
4-4 . HP 54501A
SELF CALIBRATION
The HP 54501A
has self-contained calibration
procedures that
are executed after manual ad-
justments
have been made to the System
Board Assembly
. The self-calibration routines
execute
automatic A/D, gain, offset, trigger,
and delay
calibration and store the resulting
factors to
non-volatile memory .
HP 54501A ADJUSTMENTS
SECTION 4
ADJUSTMENTS
Default values from system ROM are loaded to
non-volatile
memory as a starting reference
before
beginning adjustments on the System
Board Assembly .
When power is
applied to the HP 54501 A and
the message cal ramchecksum error re-cal in-
strument is displayed, the self calibration
procedures must be performed . Load
the
default cal factors as
instructed in paragraph
4-12, and then
perform the self calibration in
paragraph
4-17 .
If the
instrument does not pass the self calibra-
tion, perform all of the adjustment procedures
in this section . If the adjustments cannot be
made within the specified limits, one or more
of the replaceable modules must be replaced .
NOTE
An instrument warm-up of 15 minutes is
recommended before adjustment
procedures are
performed .
WARNING
Read the Safety
Summary
at
the begin-
ning of this
manual before performing
any adjustment procedures .
CAUTION
The
adjustment procedures are perform-
ed
with the top cover of the instrument
removed . Take care to avoid
shorting or
damaging internal parts of the instru-
ment .