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Model 4277A
SECTION III
iiCTIOM ill
opmAimn
3-1.
INTRODUCTION
3-2.
This section provides ail the information
necessary to operate the
Model
4277 A LCZ
Meter.
Included are descriptions of the front-
and rear-panels, displays, lamps and connectors;
discussions
on
operating
procedures
and
measuring techniques for various applications;
and instructions on the instrument's SELF TEST
function.
Warnings, Cautions, and
Notes are
given throughout; they should be observed to
insure
the
safety
of the
operator
and
the
serviceability of the instrument.
WARNING
BEFORE
THE
INSTRUMENT
IS
SWITCHED
ON,
ALL
PROTECTIVE
EARTH
TERMINALS,
EXTENSION
CORDS, AUTO-TRANSFORMERS AND
DEVICES
CONNECTED
TO
IT
SHOULD
BE
CONNECTED
TO
A
PROTECTIVE
EARTH
GROUNDED
SOCKET.
ANY INTERRUPTION
OF
THE
PROTECTIVE
EARTH
GROUNDING
WILL
CAUSE
A
POTENTIAL SHOCK HAZARD THAT
COULD
RESULT
IN
SERIOUS
PERSONAL INJURY.
ONLY FUSES WITH THE REQUIRED
RATED
CURRENT
AND
OF
THE
SPECIFIED TYPE SHOULD BE USED.
DO NOT USE REPAIRED FUSES OR
SHORTED FUSEHOLDERS. TO DO SO
COULD CAUSE A SHOCK OR FIRE
HAZARD.
CAUTION
BEFORE
THE
INSTRUMENT
IS
SWITCHED ON, IT MUST BE SET TO
THE
VOLTAGE
OF
THE
POWER
SOURCE (MAINS), OR DAMAGE TO
THE INSTRUMENT MAY RESULT.
3-3.
PANEL FEATURES
3-4.
Figures 3-1 and 3-2 identify and briefly
describe the purpose of each key, indicator, and
connector on the front panel and rear panel,
respectively. More detailed information on front
panel displays and controls is given starting in
paragraph 3-5.
3-5.
SELF TEST
3-6.
The self test function confirms correct
operation of the instrument's basic functions and
facilitates troubleshooting. It consists of three
parts: (1) ROM/RAM Test, (2) Display Test, and
(3) Analog Circuit Test.
Each is described in
paragraphs 3-7 through 3-11.
3-7.
ROM/RAM TEST
3-8.
The ROM/RAM Test is performed each
time the instrument is turned on.
During this
test, all ROMs and RAMs in the instrument's
digital
control
section
are
tested
using
a
cheek-sum test and a read/write test (RAMs
only). If a malfunction is detected, the test will
stop and an error-code will be displayed on
DISPLAY
A.
If
the
ROMs
and
RAMs are
functioning properly, the instrument will display
the HP-IB address (or output data format if the
HP-IB control.switch is set to TALK ONLY) on
DISPLAY A and the option annunciations on
DISPLAY
B and
the FREQUENCY/DC
BIAS
DISPLAY.
Error-codes
are
described
in
paragraph 3-20.
Note
If a ROM/RAM test error code, E61
through E68, appears on DISPLAY A
when
the
instrument
is
turned
on,
contact
the nearest Hewlett-Packard
Sales or
Service Office for repairs.
Note
ROM/RAM
test
error
code
E68
indicates
that
the
instrument's
continuous
memory
feature
is
not
functioning
properly.
All
other
instrument
functions,
including
measurement, are not affected.
3-9.
DISPLAY TEST
3-10.
All LED lamps and 7-segment displays on
the front panel are lit for approximately one
second when the instrument's self-test function
is initiated from the front panel or via the
HP-IB. This test is repeated until the self-test
function is turned off.
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