INITIAL
TESTS
lf
you
have
a
VOM
(volt-ohm-milliammeter)
or a
VTVM
(vacuum
tube voltmeter)
,
refer
to
Figure
1
(fold-out
from
Page
40)
and
perform
the resistance
and
voltage
tests which
follow.
These
are to insure that
there are no
short
circuits
in
the
power
supply, and that
the correct voltage
is
present.
lf
you
do not
observe the
proper
meter readings when
you
make the checks,
turn to the
"ln
Case of Diff iculty"
section.
lf
you
do not have the meters,
proceed
directly to the
"Alignment"
section.
RESISTANCE
CHECK
(
)
Set
your
ohmmeter
on its R x
10 scale.
Clip the
common
(negative)
lead
of the ohmmeter
to the
chassis and the
positive
lead
to
lug
1 of
terminal strip
BF. The resistance reading should be not
less than 150
O.
lf
you
do
not obtain this minimum
reading,
DO
NOT
connect
the Receiver
to
the electric outlet
until
the difficulty is corrected,
(
)
Disconnect the ohmmeter.
VOLTAGE CHECK
(
)
With
the
Receiver
off, temporarily
push
the two
connectors
on the black and white twisted
pair
onto
the
two speaker
lugs.
()
()
()
()
()
()
()
Position
the knob
index marks
according to
Detail
25E.
Place the ANL switch
on the rear
panel
at OFF.
Set
your
voltmeter to the
proper
range
to read 15
volts.
Connect
the voltmeter
common
lead to the
chassis.
Connect
the
positive
lead to lug 1 of terminal
strip
BF.
Insert
the line cord
into the electric
outlet and
turn
the Receiver on by rotating
the VOLUME
knob
clockwise until a click is
heard.
The
two dial
lamps
should
light and the
voltmeter should
indicate 8
to
13
volts. lf
you
see any
evidence of short
circuits
or
overheated
components
(such
as wisps of
smoke),
turn
the
Receiver off immediately
and turn to
the
"ln
Case
of
Difficulty" section.
Disconnect the
voltmeter.
Turn the VOLUME
control so
the index
mark
is at the
12 o'clock
position.
Then touch the
exposed
lead of
C22,
the 10
frF
electrolytic
capacitor
mounted
vertically
on
the circuit
board.
A hum
should
be
heard.
This indicates the
audio stages are
working.
Turn the Receiver
off and disconnect
the
speaker
leads
and
the line cords.
HICATHI<IT'
43
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