Adjustment And Calibration Procedures; Output Noise Check; Mechanical Meter Zero - HP 3400A Operating And Service Manual

Section
V
Model 3400A
PULSE GENERATOR
hp2\4A
A/J3400A
RMS VOLTMETER
5400A-6-I45Z
BNC
"T"
hp\ZS0-007Z
ELECTRONIC
VOLTMETER
hpAiOC
ELECTRONIC COUNTER
A/J5233L
©
"
O
Figure
5-4.
Crest Factor Test
Setup
This corresponds
to
a crest factor of 10
where:
Erms
E
DD
VD(1-D)
where D=,
J
PP
Tl+T
2
PP.
T
E p =
Ep
P
(l-0)
C.F.
C. F.
T 2
H
E
P
E rms
E
pp
(1-D)
E
pp
yD(l-D)
C.F.
V
D
d.
The Model 3400A should
indicate
1 volt,
±4%
(includes the
±3%
accuracy
of
410C).
e.
Adjust pulse generator pulse rate
to
250 pps
as indicated on electronic counter.
This
corresponds
to
a crest
factor
of 20.
f.
Model 3400A
should indicate
0.
5 volt,
±4%
(includes the
±3% accuracy
of
410C.)
5-14.
OUTPUT
NOISE
CHECK.
a.
Connect 50
ohm
feedthru to
3400A INPUT.
b.
Connect another
RMS
Voltmeter
to
DC
output.
c.
Set
-hp-
Model 3400A
to
0.
001
volt
range.
d.
The reading on
the
RMS
Voltmeter
should not
exceed
1
mV.
5-15.
ADJUSTMENT
AND
CALIBRATION
PROCEDURES.
5-16. The following
is
a complete adjustment
and
calibration
procedure
for the
Model 3400A.
These
procedures
should be conducted
only
if it
has previously
been
established by
Performance Checks,
Paragraph
5-5 to 5-14,
that the
Model 3400A
is
out of
adjustment.
Indiscriminate adjustment
of
the internal controls to
refine settings
may
actually
cause
more
difficulty.
If
the
procedures
outlined
do not rectify
any maladjust-
ments
that
may
exist,
and you have
carefully
rechecked
your connections
and
settings,
refer
to
Paragraph
5-29,
Troubleshooting
Procedures
for
possible
cause and
recommended corrective action.
5-17.
MECHANICAL
METER
ZERO.
5-18.
The
mechanical meter zero screw
is
located
on
the
instrument front panel.
If
the
meter
pointer
does
not indicate
zero
when
the
instrument
power
has been
off
for
at
least
one minute, mechanically zero
the
meter
following the
procedure outlined below.
a.
Turn
instrument
power
off;
disconnect
input
signal
and any
cable
connected
to
J2
(DC
OUT)
at
rear
of
instrument and allow one
minute
for
meter
pointer
to stabilize.
b.
Rotate zero adjust
CW
until
pointer
is to left
of
zero,
moving up
scale.
Continue until
pointer
is
at
zero.
If
pointer
overshoots
zero, repeat operation.
v
%L
5-4