BK Precision 1405 User Manual

TIAINTENANCE
3.
Troubleshoot
the
oseilloseope for
eause
of
the blown
fuse and repair
malfunetioning
eireuit.
IINE YOLTAGE
CONVERSION
WARNING
Aluays
disconnect scope
from
ac antlet
bef ore startfng wlt-
age
conversion
AC line
volt-
age may be
present
on the
tronsformer
whenever
the
power
cord ts
ionne cted to a
live
ac
outlet,
even
if the
POWER switctr fs
OFF.
After
conversiorq replace
the
fuse
witlt
the
cotrect value
for
the new
line wltage:
0.5
A
f
or 100
V
or
777 Y.
0.3 A
for
230 V.
The
Model
1403A
and
1405
Oseilloseopes
are faetory
wired for Ll?
volt,
50/60 Hz ae
line voltage.
They m
ay
be
rewired for 1
00
volt
or 230 volt
50/60 Hz operation by
rewir-
ing
the
power
transformer
as
shown in Fig.
11.
Remove the ease
from the unit,
Remove the soeket from the CRT.
Completely
remove the two serews
whieh attaeh
the CRT
mounting
plate
to
the rear
of the ehassis
(Fig.
8).
Remove
the entire
CRT assembly from
ehassis, ineluding the
mounting
plate
and
CRT shield
(Fig.
12).
5. Loosen the two elamping
serews
from
the
CRT
band
(Fig.
12)
and
slide
the CRT
from
the
shield.
6.
To replaee the CRT,
reverse the
proeed-
ure. Adjust
traee rotation when
the
new
CRT
is installed; see ADJUSTMENTS
seetion.
FRONT PANBL
RETIOVAL
Handle the
pnel
carcfully.
Rough handlirry may berd or
cruck the
putel.
Remove the ease.
Loosen set serews and
remove
all
knobs.
Unserew the
mounting
nut from the
SWEEP RANGE seleetor
switeh shaft.
Remove the
blaek serew from between
the
EXT SYNC/HOR
INPUT
terminal and
J
terminal.
5. Remove
two
serews
from the lower
seetion
of the
front
panel
(bottom
of
seope).
6. Carefully
pull
the
panel
forward.
the
1.
the
2.
3.
7.
CRT
REUOVAL
AND BEPLACEiTENT
WARilING
Alwcys
lwndle
CRTts
crrne-
fully.
Tfl.e
CRT is under
high
wrcuum.
Cclsless handling
may
cruck or
weakqt
the
glass,
causfng
an
ttimplosfontt.
Resulting
flytng
glcss
f
rag-
ments could
cculp injurry'.
When replacing
the
tube,
be
careful
to
place
the tube in
the socket wrth
the key
posi-
tioned in
the
Wper
left direc-
tfon
(when
viewed
from
the
f
ace).
1.
2.
3.
7.
18
t/

BK Precision 1405 Specifications

General

Brand	BK Precision
Model	1405
Category	Test Equipment
Language	English