Operating instructions
Symptom
Probable
trouble
Correction
B:
voltage
not
proper
value,
\o
filament
voltage
at
pin
11
of
J101.
Defective
h-v
circuit;
defective
filter
circuit:
ot'
defective
voltage
control
circuit.
Defective
filarnent
voltage
vibrator
E102
and
associatecl
components.
Localize
tt'ouble
(b
below),
and
re-
place
defective
part.
Localize
tlonbÌe
(ó
below),
and
re-
place
clefective
part.
b.
Localizíng
T t'ouble.
Symptom
Probable
trouble
Correction
Relay
K101
does
not
trip
in
11b-
volt
a-c
operation.
No
input
voltage
to
power
supply;
open
fuse
shor,ted
capacitor
C11B
or
Cl14.
Defective
voltage
regulator
tubes;
R111,
R112,
or
R11B
open.
Shorted
capacitor
C118;
burned-out
resistor
R115
or
R116;
defective
V104.
Repair
or replace
defective
com_
ponent.
Replace
defective
vibrator
or
part.
Replace
defective
part.
Replace
defective
part.
Replace
defective
part.
Check
and
replace
V102,
R101,
R106,
C113,
or
C114.
Check
secondary
of T102.
resistor
Check
tubes.
Replace
rlefective
part.
Replace
defective
part.
F101
(110V.1A.)
;
open
coil
of relay
or
de_
fective
transformer
T101;
capacitor
C102
shorted
or
CR101
defective;
capacitor
C101
shorted.
Burned-out
fuse
F104;
defective
vibrator.
No
input
voltage
to
vibrator
contacts;
open
or
sholted
tut,ns
on
tlansformer
T10à
pri_
mary;
coil
L]01,
L]02,
L]03,
L104,
or Lì0b
open;
capacitors
C104
through
C109
or
C112
shorted.
Bnlned-out
fuse
F10B;
Defective
vibrator;
no
input voltage
to vibrator
EI0l;
shor.ted
ol
open
turns
of
transformer
T102 primary,
open
r.esistor
R104;
L104
or
L10b
open:
shorted
capacitor
C107
or
Cl0g.
Burned-out
fuse
F102;
defective
vibr.ator;
no
input
voltage
to
vibrator
E101;
shorted
or
open
turns
of
transfornrer
T102 primary;
open
resistor
R10il,
R10b,
or
R107:
L104
oi'
LI05
open;
capacitor
C107
or
C10g
shorted.
i
Defective
h-v
circuit;
defective
tube
or
filament
circuit;
defective
transformer:
No interrupted
voltage
at vibra-
tor
E101
for
6-volt
d-c
opera-
tion.
ì*o
inten'upted
voltage
from
vi-
bi'ator
E101
for 12-volt
opera-
tion".
\o inter.rupted
voltage
from
vi-
blator
E101
for 24-vo1t
opera-
tion".
\o
81
voltage
at
junction
of
R110
and
C114.
\o B1
output
voltage
after
pre-
vious
checks
have
been made.
\o voltage
at
cathode
(pin
b)
of
\'104
for
6-,
!2-,
or 24-volt
op-
elation
after
previous
cheeks
have
been
made.
Defective
'''iring;
defective
rectifier
cR102;
Repair
o'replace
defective
parts.
defective
tr,ansformer
secondary
of T10B:
defective
filament
filtel
circuit;
L106
or
Ll07
open
;
Cl10
or.
Cll
I
shorted.
'I'v
AN
EMERGENCy'
rot
72-
or
24-volt
d-c
operation
onlv,
shoull
corìtact
1
or ó
or
both
of
E10r
become
defective
and if
the vibrator
wi'
r:ilì
tibrate
and
thefe
are no
spares
on han<],
the
leads
on
terminals
1 and
2 ancl
terminals
4
and
b of E101
fiÌter
may
be interchangerì.
.{
tae
should
be
put
on
the
porver
supply
noting
the
changes
macle.
\o
filament
voltage
at
pin
11
of
J101
aftel
all
previous
checks
have
been
made.
78.
Trouble-Shooring
Chorrs
for
Rqdio
Receiver
R-174lURR
(figs.
38,
39,
and
4b)
fhe
following
charts
are
supplied
as
an
aid
ìocating
trouble
in
the
receiver.
These
charts
'
the
symptoms
which
the
operator
or
serv_
,r
jl13A
iceman
may
observe,
either
visually
or
aucìibl1,,
while
making
a few
simple
tests.
The
chet.ts
also
indicate
hou
to sectionalíze
trouble
qt,ir:l;ltl
to
the
particular
stage
or
cit,cttit.
The
si.snal
substitution
tests
ouilined
in
paraglaphs
g0
through
84
then
can
be
used
to
sr_rpplement
thls
59