BK Precision 1405 - TROUBLESHOOTING (CONTINUED); TROUBLESHOOTING VERTICAL DEFLECTION CHECK; TROUBLESHOOTING SWEEP RANGE AND SYNCHRONIZATION; TROUBLESHOOTING SYNC SIGNAL APPLICATION

TROI'BLESHOOTING
OPERAIIONAL
CHECK
10. Apply
0.4
V
p-p
sine wave
(0.14
V rms)
at
1 kHz
to
VERT INPUT
jaek.
Set
V
ATT
switeh
to 1/10. Again
there
should
be
about
4
division
of vertieal
defleetion.
!4.
Synehronized
waveform
display should
be
obtainable
on 100-1
k
SWEEP
RANGE.
Apply
4 V
p-p
sine wave
(1.4
V rms) at
10 kHz to VERT
INPUT. Set
V
ATT
switeh
to
1/100. Again there
should
be
about
4 division of vertieal
defleetion.
Synehronized
waveform
display should
be
obtainable
on 1
k-10
k
SWEEP
RANGE.
Leave sine
wave applied
to the
VERT
INPUT
jack
and
also
apply
it to
the
EXT
SYNC/HOR
INPUT
jaek.
Set
SYNC
switeh
to EXT.
Reduee
signal
to
2 V
p-p.
Synehronized
waveform
display
should
be obtainablq
Set AC-DC
switeh
to
DC.
Apply
4
V
P-P
square wave
or sine
wave
with
+2
V de
offset to
VERT INPUT
jaek.
Waveform
display should
be
vertieally
eentered
about
+2
divisions
(extend
from 0
to
+4
divisions), Set
AC-DC
switeh
to AC.
Waveform should
be eentered
about
0.
Apply
3
V
p-p
sine wave
(1.05
V
rms)
at
60 Hz to EXT
SYNC/HOR
INPUT
jaek.
Return
SWEEP
RANGE switeh
to EXT
position.
Set SWEEP
VARI/EXT GAIN
eontrol
to
maximum
(fully
eloekwise).
There should
be approximately
10
divi-
sions
of
horizontal defleetion.
Apply
10 V
p-p
signal
between
V DIR
and
GND terminals. Set
NOR-DIR
switeh
to
DIR.
A waveform
of about
1 division
amplitude
should
be displayed.
TROI'BI,BSHOOIING
If
no or
ineomeet
vertieal
defleetion
eheek
I/n
attenuator
51,
R102,
R106,
C102'
TC102.
Cheek
C4,
52.
v
11.
L2.
If
no or ineorreet
1/100 attenuator
TC101.
vertieal
defleetion
eheek
sl,
R101,
Rl05,
Cl01,
13.
Cheek
C5, S2.
Cheek
R1, C2,
s4.
Cheek
S3, Cl.
Ineorreet
amount
of
horizontal
defleetion
indieates
need
for
HOR
GAIN
adjustment
vR102.
:
15.
16.
Ll.
22
Cheek
55, C6,
C7,
R2,
R3.
v