BK Precision 1403A User Manual

TROITBLESHOOT'ING
6.
OPEBATIONAL
CHECK
4. Rotate
<>POSITION
eontrol
to
both
extremes.
Dot
should
be adjustable
beyond. the
left and
right edges
of the
sereen.
Adjust
dot
to
horizontal eenter
of sereen,
5.
Set SWEEP
RANGE
switeh
to
10
k-100
k
position.
A traee
should
be displayed
on
the CRT.
A
sharp,
elear
traee
should
be
obtainable
by adjusting
the
FOCUS
and
INTENSITY
eontrols.
Rotate
V GAIN
eontrol
from
one
ex-
treme to
the
other.
The
traee
should
not
shift
more than
1 division.
Apply
40
mV
p-p
sine
wave
(14
mV rms)
at
100
Hz
to VERT
INPUT
jaek.
Set
V
ATT
switeh
to
rrlrt
(10
mV/DIV)'
V
GAIN
eontrol
to
maximum
(futly
eloekwise),
and
AC-DC
switeh
to AC.
There
should
be
approximately
4 divisions
of
vertieal
defleetion.
The
waveform
display
may
be unsynehronized.
Set
SWEEP
RANGE
switeh
to
10-100
position.
Set
SYNC
switeh
to
INT
and
adjust
SWEEP
VARI/EXT
GAIN eontrol
Synehronized
display
of waveform
should
be
obtainable.
Reduee
vertieal
deflee-
tion
to
1
division amplitude.
Synehron-
ized
display
should
still
be obtainable.
TROUBTESHOOIING
Non-eentered
or
laek
of
adjustment
range
indieates
horizontal
ehannel
problem. Meas-
ure
voltages
at
Q114,
Q115'
Q116.
No
traee
indieates
failure
of low
voltage
power
supply,
sweep
generator, or
horizontal
final
amplifier.
With
another
seope,
eheek
for
sawtooth
wave-
form
at
emitter
of
Q113.
If
no sawtooth'
eheek
voltages
at
Q112,
Q113.
If sawtooth
present
at
Q113'
eheek
sawtooth
waveform
at
Q115,
Q116
eolleetors.
Measure
voltages
at
Q114,
Q115'
Q116.
Improper
operation
indieates
failure
in
FOCUS
or
INTENSITY
eireuil
Cheek
VR103'
VR104'
R158-R166,
elzl,
e122.
Shift
of
traee
indieates
need
for DC
BAL
adjustm
ent
VRl01.
No
vertieal
defleetion
indieates
failure
in low
voltage
power
supply
or
vertieal
ehannel
With
another
seope,
eheek
presenee
of
sine
wave
signal at
Ql02-Q111.
Measure
voltages
at
Q101-Ql11.
If
display
eannot
be synehronized,
first
eheek
sawtooth
wavef
orm
at
Q
1 13 em
itter
with
another
seope.
Make
sure
sawtooth
is adjust-
able
from
about
10
Hz
to
100
Hz
with SWEEP
VARI/EXT
GAIN
eontrol
If
not,
eheek
C3'
VR104,
and
Ql12,
Q113
eireuit.
If
sawtooth
frequeney
is okay,
eheek
R131'
R132,
54,
C10?,
D101.
!7.
8.
9.
21

BK Precision 1403A Specifications

General

Brand	BK Precision
Model	1403A
Category	Test Equipment
Language	English