Fluke 8050A Instruction Manual page 33

OPERATION
CONDUCTANCE
MEASUREMENT
2-68.
DIODE
LEAKAGE
TESTS
2-69.
Diode
leakage
(Ir) tests
require that the
diode
junction
be
reverse biased while being measured.
Connect
the
anode
of the
diode
to the
COMMON
input
connector
to
reverse bias a diode junction.
A
good
silicon
diode
will
produce an
in-scale
display reading
on
the 200
nS
range
when
reverse biased.
2-70.
TRANSISTOR TESTER
2-71.
The
transistor
tester
described
in
the following
paragraphs provides approximate
test
information. Beta
is
tested using a
Vce
of
2V
and an
Ic of about 200
/xA.
This transistor
tester
is
useful for
checking
the
proper
operation of
transistors
and approximate
beta values for
comparative measurements.
2-72.
The
transistor tester fixture
is
described
in
Figure
2-1
2.
When
assembled and connected
to
the
V
/
kfl/
S and
the
COMMON
input connector, the
8050A
can be used
to
determine
the
following information about
transistors:
»
Transistor type
(NPN
or
PNP)
®
Defective transistors (shorted or open)
®
Collector-to-emitter leakage
(Ices)
® Beta
from
10 to 1000
in
a
single range.
2-73.
Transistor type
is
determined by
setting the switch
on
the tester fixture to
BETA,
setting the
8050A
to the
2
mS
range,
and
observing the display
reading.
If
a
low
reading (<
0.0100)
is
displayed, reverse the
test fixture at
the input connectors.
If
the collector of the transistor
is
now
connected to the
COMMON
input connector
the
transistor
is
a
PNP
type.
An
NPN
type
will
have
its
collector
connected
to
the
V/kfl/S
input connector.
2-74, Defective Transistors
2-75.
If
the transistor
is
defective, the following
indications will
appear, regardless of
transistor type or
test
position:
1.
An
open
transistor
will
produce a display
reading of 0.0005 or
less.
SCHEMATIC
TRANSISTOR
UNDER
TEST
TEST FIXTURE
CONSTRUCTION
Si
TOGGLE
SWITCH
J1
TRANSISTOR
TRANSISTOR SOCKET
CONNECTOR
0.75"
SPACING
SWiTCHARM
GENERAL
RADIO TYPE
274
MB