TM 11-6625-539-14-4
7-17. Beta Measurement Test (Out-of-Circuit)
one germanium, covering beta ranges of 1 to 100,
100 to 1000, and 1000 to 10,000.
a. Test Equipment and Materials. Three good
transistors the beta values of which have been
b. Test Connections and Conditions, As indi-
tested on a standard transistor test set and whose
cated below.
values have been recorded. Selection should in-
c. Procedure.
clude at least one NPN, one PNP, one silicon, and
Control settings
Step
Test procedures
Performance
standard
Equipment
No.
Test
under test
equipment
a. Meter deflects to indicate to
a. Insert one transistor in panel-
1
N/A
POLARITY switch:
w i t h i n 3 percent of beta
N P N or PNP to
mounted test socket.
value recorded on standard
c o r r e s p o n d with
transistor tester. Record indi-
selected transisor.
cated value.
b. Meter deflects to indicate
FUNCTION switch:
b. Insert second and third tran-
within 3 percent of beta val-
BETA.
sistors in panel-mounted test
ues recorded on standard
socket.
RANGE switch: ap-
transistor tester. Record indi-
propriate for se-
cated value.
lected transistor.
7-18. Beta Measurement Tests (In-Circuit)
(2) 500-ohm, l-percent resistor.
b. Test Connections and Conditions. As indi-
a. Test Equipment and Materials.
cated below.
(1) Same three transistors used in previous
c. Procedure.
test.
Control settings
Step
Performance standard
Test procedures
Test
No.
Equipment
Equipment
under test
a. I n s e r t o n e t r a n s i s t o r i n
a. Record beta for transistor
1
POLARITY switch:
N/A
under test.
N P N or PNP to
panel-mounted test socket.
c o r r e s p o n d with
s e l e c t e d transis-
tor.
b. Check that beta for transis-
FUNCTION switch:
b. Connect 500-ohm resistor
tor under test is within fol-
BETA.
across emitter-base terminals
lowing ranges: 5 percent
of transistor.
RANGE switch: ap-
within 1 to 100 range when
propriate for se-
compared to out-of-circuit
lected transistor.
readings. 5 percent in 10 to
1000 range when compared to
out-of-circuit readings. 30
percent in 100 to 10,000 range
when compared to out-of-cir-
cuit readings.
c Performance standards must
c. Connect 500-ohm resistor
be same as above.
across collector-base termi-
nals of transistor under test.
Performance standards must
d
d. Connect 500-ohm resistor
be same as above.
across collector-emitter ter-
minals of transistor under
test.
2
a. Insert second and third tran-
N/A
a. Record betas for transistors
Same as above.
sistors in panel-mounted test
under test.
socket.
b. Connect 500-ohm resistor
b. Performance standards must
across transistor terminals
be within same limits as de-
s u c c e s s i v e l y as described
scribed above.
above.
7-11
