Operating instructions
Maintenance-71380
Transistor Tester
(Cont
.)
Multimeter
Recommended
Tektronix
types
:
576
Curve
Tracer,
577/177
Curve
Tracer
system,
7CT1
N
Curve
Tracer
unit
and
a
7000-series
oscilloscope
system,
or
a
5CT1
N
Curve
Tracer
unit
and
a
5000-series
oscillo-
scope
.
Description
:
Voltmeter,
10
megohm
input
impe-
dance
and
a
range
from
0
to
at least
50
volts
dc
;
accuracy, within
0
.1%
.
Ohmmeter,
0 to
20
megohms
.
Test
probes
should
be
insulated
to
prevent
accidental
shorting
.
Purpose
:
Check
voltage
and
resistance
.
Test
Oscilloscope
Description
:
Frequency
response,
do
to
100
mega-
hertz
minimum
;
deflection
factor,
5
millivolts
to
5
volts/division
.
A
10X, 10
megohm
voltage
probe
should
be
used
to
reduce
circuit
loading
.
Purpose
:
Check
operating
waveforms
.
TROUBLESHOOTING
TECHNIQUES
The
following
troubleshooting
procedure
is
arranged
to
check
the
simple
trouble
possibilities
before
proceeding
with
extensive
troubleshooting
.
The
first
few
checks
ensure
proper
connection,
operation,
and
adjustment
.
If
the
trouble
is
not
located
by
these
checks,
the
remaining
steps
aid
in
locating
the
defective
component
.
When
the
defective
component
is
located,
it
should
be replaced
using
the
re-
placement
procedure
given
under
Corrective
Maintenance
.
Troubleshooting Procedure
1
.
CHECK
CONTROL
SETTINGS
.
Incorrect control
set-
tings
can
indicate
a
trouble
that
does not
exist
.
If
there
is
any
question
about
the
correct
function
or
operation
of
any
control,
see
the
Operating
Instructions,
section
2
.
2
.
CHECK
ASSOCIATED
EQUIPMENT
.
Before
trouble-
shooting,
check
that
the
equipment
used
with
this instru-
ment
is
operating
correctly
.
Check
that
the
signal
is
pro-
perly
connected and
that
the
interconnecting
cables
are
not
defective
.
Also,
check
the
power
source
.
If
the
trouble
persists,
the
time-base
unit
is
probably
at
fault
.
3
.
VISUAL
CHECK
.
Visually
check
the
portion
of
the
instrument
in
which
the
trouble
is
located
.
Many
troubles
can be
located
by
visible
indications
such
as
unsoldered
connections,
broken
wires,
damaged
circuit
boards,
damaged
components,
etc
.
4
.
CHECK
INSTRUMENT
ADJUSTMENT
.
Check
the
ad-
justment
of
this
instrument,
or
the
affected
circuit
if
the
trouble appears
in
one
circuit
.
The
apparent
trouble
may
be
the
result
of
misadjustment
.
Complete
adjustment
instruc-
tions
are
given
in
the
Performance
Check
and Adjustment,
section
5
.
5
.
ISOLATE
TROUBLE
TO
A
CIRCUIT
.
To
isolate
trouble
to
a
circuit,
note
the
trouble
symptom
.
The
symp-
tom
often
identifies
the
circuit
in
which
the
trouble
is
located
.
When
trouble
symptoms
appear
in
more
than
one
circuit,
check the
affected
circuits
by
taking
voltage
and
waveform
readings
.
Incorrect
operation
of
all
circuits
often
indicates
trouble
in
the
power
supply
.
Check
first
for
correct
voltages
of
the
individual
supplies
.
However,
a
defective
component
elsewhere
in
the
instrument
can
ap-
pear
as
a
power-supply
trouble
and
may
also
affect
the
operation
of
other
circuits
.
Figure
4-6
provides
a
guide
for
locating
a
defective
circuit
.
Start
at
the
top
of
the
chart
and
perform
the
checks
given
on
the
left
side
of
the
page
until
a
step
is
found
that
does
not
produce
the
indicated
results
.
Further
checks,
or
the
circuit
in
which
the
trouble
is
probably
located,
are
listed
to
the
right
of the
step
.
The
shaded
blocks
on
the
Trouble-
shooting
Chart
indicate
circuit(s)
that
may
cause
instru-
ment
malfunction
.
The
circuit(s)
listed
in
shaded
blocks
are
discussed
in detail
in
the
Theory
of
Operation
section
of
this
manual
.
This
chart
does not
include
checks
for
all
possible
defects
;
use
steps
6
and
7
in
such
cases
.
After
the
defective
circuit
has
been
located,
proceed
with
steps
6
and
7
to
locate
the
defective
component(s)
.
6
.
CHECK
VOLTAGES
AND
WAVEFORMS
.
Often
the
defective
component
can
be
located
by
checking
for
the
correct
voltages
and
waveforms
in
the
circuit
.
Refer
to
the
diagrams
section
at
the
rear
of
the
manual
for
typical
vol-
tages
and
waveforms
.