Teble 8-3. Output Circuit.
(Continued)
Indication: Function outputs missing
or
clipped when TTL sync output OK. Problem with triangle waveform.
Check
4.
Rotate
AMPLITUDE cw
(MAX).
DC OFFSET to OFF. and check 500 OUT
(HI)
for a 20V Pi>
(open circuit)
t
rian
g
le
.
5. Check for
excessive discontinu ities
at the triangle peaks near the
bottom
o
f
a
frequency range
(other than
x 1 to
x
100).
6. Check for nonllnearities in the triangle
slopes
near
the
bottom
of a fre
Quency range
(other
than
x
1 to
x
1 00).
7
.
Check for a waveform symmetry problem.
Tabl. 1-4. Sin. Conv.rslon
Indication: Sine waveform orab/em.
Check
1 . Set controls to initi
a
l
positions (refer
to paragraph
6
.
4
)
.
2. Check emitter al l for
a
4 kHz.
±
1 .2SV
triangle.
3.
Verify
that the
±
1 .25V triangle peaks at the emitter 01 01 agree within 3%
.
4
.
Select triangle function; check for
±
1 .25V triangle at U 1 3 pin 1 0.
5. Select sine
function;
check ror
±
1 .25V sine at U 1 3 pin
1 0.
6.
Check
sine distortion 500 OUT
(HI)
per
calibration
procedure (rerer
to
table 5.1 ).
7. Check sine amplitude
vs
frequency per
s
pe
cif
i
catio
n
s
.
(
refer to section 1 ).
Scans by ArtekMedia
=>
2011
Corrective Procedure
a.
Output
amplifier
circuit.
b. E1 5, E1 6
w
i
ring
.
a .
U5.
b
.
SOR signal at cathode
CR1 0
not ±
2 . 5V
.
a
.
Associated timing capacl·
tor or C36.
b. US. CR6
.
c.
09.
010
.
Go
to table
6-8
.
Corrective Procedure
Check for nOrmal ope
r
at
i
on
.
Go
to
table 6-2.
a.
R62. R63. R64. R6S.
R67. R68. R70.
b.
CRB. CR9, U7.
c. ±
1 5V supp
li
es
.
Go
to
table 6-3, step 3.
a
.
U1 2 ci rcuitry.
b. SWI 2.
a
.
R97. R1 1 4
adjustments.
b
.
Waveform
s
y
m
metry
.
R45
adjustment
and table 6-8.
c.
U1 2 circuitry.
C47. C55, C56, C57.
Summary of Contents for 188
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