Wavetek 188 Instruction Manual page 32

Indication: Function outputs missing
(open c i rcuit)
4. (HI) AM PLITU DE cw
Rotate
for a 20V Pi>
Check for
5.
excessive discontinu ities
f frequency ra nge
a
o
Check for nonllnearities in the triangle
6. (other
Quency range than
7 . Check for a waveform symmetry problem .
Indication: Sine wa veform orab/em.
Set controls to initi l
1 .
a
2.
Check emitter al l for
Verify
that the 1 .25V triangle peaks at the emitter 01 01 ag ree within 3%
3.
±
4. Select triangle function; check for
function;
5. Select sine check ror
Check
6. si ne distortion 500 OUT
table 5. 1 ).
7. Check s i ne amplitude
Teble 8-3. Output Circuit.
clipped when TTL sync output OK. Problem with triangle waveform.
or
Check
(MAX ) .
DC OFFSET to OFF. and check 500 OUT
triangle.
at the triangle peaks nea r the
(other than 1 00).
x 1 to
x
1 00).
slopes
1 to
x x
Tabl. 1-4 . Sin. Conv.rslon
Check
positions (refer
to paragraph
a
4 kHz. 1 .2SV
±
triangle.
1 .25V triangle at U 1 3 pin 1 0.
±
1 .25V si ne at U 1 3 pin
±
(H I)
per
calibration
specifications.
f requency per
vs
Scans by ArtekMedia
(Continued)
bottom
near bottom
the of a fre­
6.4).
.
1 0.
procedure (rerer
to
(refer to section 1 ).
201 1
=>
Corrective Procedure
amplifier
circuit.
a. Output
b. E1 5, E1 6
wi ring .
U5.
a .
b. SOR signal at cathode
CR1 0
not ±
2 . 5V.
Associated timing capacl·
a.
tor or C36.
b. US. CR6.
09.
0 1 0.
c.
Go
to table 6-8.
Corrective Procedure
Check fo r nOrmal operation.
to
Go table 6-2.
R62. R63. R64. R6S.
a.
R67. R68. R70.
CRB. CR9, U7.
b.
1 5V supplies.
c. ±
to
Go table 6-3, step 3.
U 1 2 ci rcuitry.
a.
b. SWI 2.
adjustments.
R97. R 1 1 4
a .
b. Waveform adjustment symmetry. R45
and table 6-8.
U 1 2 ci rcuitry.
c.
C47. C55, C56, C57.