Wavetek 188, Инструкция по эксплуатации

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2.
Opened capacitor can be
located (
but
not always)
by using
a
good capacitor connected
in parallel
with the capacitor
under
test
and
observing the
resu l ting
effect.
8.4 GEN ERAL INSTRUCTIONS
When encountering
a
problem,
it is advisable
to return
as many
of
the
front p
a
n
e
l
controls
as possible to
their
Initial
settings and
stil l
retain the problem. The trouble­
shooting
tables
in
this
section generally begin at these
initial settings and
specify
all subsequent setups.
Preset
the front panel
controls
as
follows.
Control
Position
Frequency
Dial
. . . . . . . . . . . . . . . . . . . . . . . . . . .
4.0
POWER
. . . . . . . . .
, . . . . . . ' , . . . . . . . . . . , . . . . ON
FREO M U LT
(Hzj
.
, . . . . . . . . . . . . . . . . . . . . . . . . 1
K
FUNCTION .
. .
. .
. .
.
. . . . .
.
.
.
. .
.
. .
.
. .
.
. .
. .
'"
DC OFFSET
. .
.
. .
. .
.
.
.
. .
.
. . .
.
. , . . . . . . . . . . OFF
AMPLITUDE
.
.
. .
.
. . . . . .
.
.
.
, . . . . . . . . . . . . . MAX
SWEEP
. .
.
, . . . . . . . . . . . . . . . . . . . CONT, STOP, LIN
CAUTION
To prevent damage to components, turn
unit off while removing
or
replacing
components, connectors
or
pc boards.
The suspected
ma lfunctioni ng
condi tion
should
be
double
checked to eliminate the
po.ssI bllltyof improper
settings
or connections.
Before
attempting
fau lt
isola­
tion ,
the unit should be checked for proper line
voltage selection
(refer to
Section
2).
A
good
visual in­
spection
of the boards and chassis wires for
damage
or overheati ng
often
saves
much time.
Once the
malfunction
is
defined,
begin the isolation
procedure by
selecti ng an
indication in
table
6-1
wh ich
best
describes
the
malfunction and
proceed
to
the referenced troubleshooting table.
Follow through the checks
in
the
troubleshooting table,
using schematics and
assembl ies
as a guide. When
positive
results
are not obtained, perform the in­
dicated corrective procedure.
Table 8-1 .
Faul� I.olallon
Incllcatlon
1 .
Fuse blown,
no
power
indication or no
Table
outputs. 6-2
2. Function
outputs
misSing or clipped 6-3
when TTL sync OK.
Triang le
problem.
3. Sine waveform problem.
4.
Square
waveform
problem.
5. TTL sync output
problem .
6. Generator frequency does not respond
correctly
to dial and VCG input.
7. Waveform symmetry
problem.
8.
Problem
on
bottom three ranges
only .
9.
Generator
trigger
and gate mode
prob-
lem .
10.
Sweep problem.
6-5
6-7
6-8
6-9
6-1 0
6-1 1
Table 8-2. Power Supplle. and Generator LOOp
Indication : Fuse blown,
no
power indication
or no
outputs.
Check
1 . Set all controls in their
initial positions
(refer to paragraph 6.4).
2. Ensure line voltage matches instrument configuration
(refer
to Section
2).
Check f u se .
3. Check C1
( + )
and C2
(
- )
for
±
20
to 26V unregulated
dc.
6-2
Scans
by
ArtekMedia
=>
2011
Correctl,e Procedure
Replace fuse; check for nor­
,mal
operation .
a.
CRl
-
CR4.
b. Cl , C2.
c.
SW1 .
d. Tl , RV1 ,
F1 (bracket
as­
sembly).