HP 4328A Service Manual

Section V
Paragraphs 5-11 to 5-22
5-11. MAINTENANCE
5-12. Service information m the form of trouble-
shooting, waveforms, schematics and component loca-
tions are given m Section VIII. Also, an overall sys-
tem block diagram is included which contains keyed
numbers correspondmg to the test points.
5-13. 4328A PERFORMANCE CHECKS
5 -14.. The performance checks presented here are
front panel operations designed to compare the Model
4328A wlth its published specifications These opera-
tions should be conducted before any attempt is made
at instrument calibration or adjustment During per-
formance tests, periodically vary the Une voltage sup-
plied totheModel4328A, ±:1000on eitherll5 or230 V
operation A 1/4 hour warm-up period should be al-
lowed before these tests are conducted.
5-15. MECHANICAL METER ZERO.
5-16. If necessary, mechanically zero the meter
movement as follows.
a.. With instrument turned off, rotate meter adjust-
ment screw clockwise until pointer approaches
zero mark from the left.
b. Continue rotatmg clockwise until pointer com-
cides with zero mark. If pointer overshoots,
continue rotating adjustment screw clockwise
until pointer once again approaches zero mark
from the Left.
c. Rotate adjustment screw about three degrees
counterclockwise to disengage itfrom the meter
suspension
5 -17.. LINEARITY CHECK
a.. Attach the Model16005A probe to the 4328A and
set the range switch to 100R
Table 5-2. Linearity Test
Standard HP Model
HP Model
Decade 4328A
4328A
Resistor Meter
Range
Settmgs
Readings
Settings
on
0
10
8 -
12
20 18 -
22
30
28 -
32
40 38 -
42
50 48 -
52
won
60
58 -
62
70
68 -
72
80
78 -
82
90 88 -
92
100
98 - 102
5-2
Model 4328A
b.. Connect the Model 4328A probe to the Decade
Resistance Box ( YEW Type 2792 or GR Model
1432T)
c.. Switch the Decade Resistor, providing 0 to 1 00&1,
in 10n steps.
d.. The Model4328A should read as shown in Table
5-2.
5-18 FULL SCALE CHECK
a Attach the Model 16007AiB Test Lead to the
Model 4328A.
b
Connect the Test Leads to Standard Resistor of
0 .. 001 to lOOn and check the full scale readings
of the Model 4328A. The Meter should read as
shown in Table 5-3.
5-19. COVER REMOVAL AND REPLACEMENT
5-20. The side covers can be removed and replaced
independently of the top and bottom cove r.s. Each side
cover 1s held in place by four screws retamed by nuts
whlch are fastened to the side frames.
5-21. TOP COVER REMOVAL
a. At the rear of the instrument, remove the screw
that retams the cover.
b. Grasp the cover from the rear, and slide it back
1 · 2 inch.. Then tilt forward edge of the cover
upward and hft the cover from the instrument ..
5-22 TOP COVER REPLACEMENT
a. Rest the cover flat on the cast guides projectlng
mward near the top of each side frame.
Table 5-3.. FuLl Scale Test
Standard HP ModeL HP Model
Resistor
4328A
4328A
Meter Range
Readings Settings
0 .. 001 f.!
0. 00098 -
0 ..
00102 r2 0 ..
001 n
t ( 0
003 0
00294 -
0 .. 00306
0 ..
003)
0 ..
01
0.0098
-
0 .. 0102 0 .. 01
0.03 0.0294
-
0.0306 0 .. 03
0
.. 1
0 .. 098
-
0.102
0. 1
0 .. 3
0.294
-
0 .. 306 0 .. 3
1
0 .. 98
-
1. 02 1
3
2. 94
-
3.06
3
10
9 .. 80
-
10 .. 2
10
30 29 .. 4
-
30.6 30
100 98.0 - 102 0
100
* YEW TYPE 2872 only.

HP 4328A Specifications

General

Brand	HP
Model	4328A
Category	Measuring Instruments
Language	English