Agilent Technologies 339B Service Manual

P
ower
Supply
Section
Figure
4-6
shows
the
P
ower
Supply
Section
block
diagram.
Figure
4-6.
P
ower
Supply
Section
Block
Diagram
The
ac
line
power
is
connected to
the
A5
A
C
Inlet
Board
Assembly
,
which
consists
of
a
fuse
,
line
switch,
and
varistors
.
The voltage
selection
switch
selects
the
ac
line
voltage
from
230V
or
115V
.
A
ccording
to
the
selection, the
ac
line
power
is
connected
to
the
corresponding
primary
tap
of
the
transformer
.
V
aristor VR1
protects
the
circuit
from
surge
voltage
on
the
line
power
.
VR2
blows
fuse
F1
if
the
4349B is
turned on
with
the
wrong
line
voltage
setting
selection,
for
example,
115V
selection
when
using
a
230V
line
.
The transformer
secondary voltage
is
approximately
14
V
.
This
ac
voltage
is
rectied
and
ltered by
circuitry on
the
A1
Main
Board
Assembly
,
and
produces
approximately
14
Vdc
.
The
dc voltage
is applied
to
the
DC-DC
Converter
to
produce
regulated
+5V
,
+12V
,
and
0
12
Vdc
.
The dc
voltages are
supplied to
all
the
assemblies
,
either
directly
or
indirectly
via
the
A1
assembly
.
4-8 Troubleshooting

Agilent Technologies 339B Specifications

General

Brand	Agilent Technologies
Model	339B
Category	Measuring Instruments
Language	English