Instruction manual
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In"n
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CONTILOL
ADJIISTMENTS
0) TheINPUTLEVELADJ.
conlloll.ln.ended
to protectthe
sPeaker
system
from"ubICllting"
should
lOIMOne
tum the
preampllfler-eontrol unit level control. to full, by pe
.....
milling
1""
to
attenuate.he
preampllfl.r
aulput
.Ignal by
OoY"'lrod
amount
at
.he
Inpu'
to.he
power amplifier
where It
can
not
be
"fiddled"
wlth~
Start
by
..
ttlng the
INPUT
LEVEL
maximum
ccxnter--cloclcwl
..
(maximum
at..
tenuatlon~
using a screwdriver. Set the LOUDNESS
con-
trol on your preamplifier to the
maxlmumclodk'Nl
..
1'011-
tion
and
the
LEVEL
control at the midpoint of Its range of
rotation. Tum your
phonograph
on
CIld
play on overage
orchestral record.
Then
slowlyortate the
JNPUT
LEVEL
ADJ.
control clockwise until the--muslc II
at
normal (or
concert) IIttenlng level.
This
complet.
the adJustment,
whleh need not
b.
repeated.
b)
ON-OFF
SWITCH.
Should be used In
ON
posltlan
when
unit
I. used with a preampllfter. It may
be
used
ell
a
pow.r
on-off
switch
when
the amplifier I,
accessible.
TROIlBLE.SHOOTlNG
PROCEDIIRES
YouraJnPlTfleuhouldrequire little Mrvlce exceptfor nor-
mal tube replacement. W. recommend no substitutIons
lar
.he
lube IypeI us.d In thl. ampllfl.r. The
EL84,
and
EZ81lypelare dl.tributed natlanallyby.heAmperex
El.c-
IIonlc Carporallan (230 Duffy
Ave.,
Hlcksvill.,
L.I.,
N.
Y.)and
MJllard Ltd. (lntematlonal ElectrOnlcsCorp.,
81
Spring 5••,
N.Y.
12,
N.
Y.)
If n
......
ry, repleee-
ments
CCII
be obtained directly from EICO.
To
facilitate
servicing, remedial andtrouble-shootlng
pro-
cedures have been p<avldedIn the
TROUBLE
SHOOTING
CHART
that
falla,...
A VOlTAGE AND
RESISTANCE
CHART
Is 01.0 provided as an
aid
In
locating
defective
components
and
to pennlta .corefu
I~
stage~y-stage
check
0'
the amplifier. DCoperating
voltagu
are
"Iv.,
both
at
no Ilgnal and
at
a
slpl
developing 14 wattsoutput as
~II
as
the
cormpondlng
1kc signal
voltages.
ToIsolate the sourceof unusual humor noise in your
system,
flnt
turnofftheACpOwerandthen
unplug
the
audio
cable
connecting to
the
amplifier input. Then
tum
th.AC power
on again and note whether
hum
or nol.e
has
decreased.
If It has, the fault Is in the preamplifier or associated
equipment
and
measures should be teken to
correct
It os
described in the servlce notes fo'r these units. If
it
Is de-
.ired to provide a good building ground for your
entire
system, run a
lead
from under speaker
connection
termInal
"Gil to a
cold
water
pipe.
Do
not
COM.ct such a ground
wire to
other
components in the s)'Item.
If
the
trouble Is no output or low
output
and
the
amplifier
is suspected, check AC signal
voltagn
stortlng at the
In-
put
and
working step"'by""Step
toward
the
output, using a
slne-wave
audio signal generator
and
0 VTVM. Set the
Inpu
••
Ignal to 1 vol.. The .arrespandlng grid
and
plate
slpoKll
voitaguforthllinput
are
Indicatedon theschematlc
dl_.
Thl. procedure .heuld
.ufflce
to locall
..
the
defectl.,.
Itage.
IF
the
trouble Is an' axcl!llllval)' distorted output, try tube
replacement, signal tracIng or
precede
directly
to
volt.
and
resistance
lnIIIQIUrements.
When the deFective
It
age Is
loCQUzecl,
procede
to a re-
sistance
and
voltage
check
of
the
stage,
using the dataIn
the
Resistance
and
Voltage
chart.
Disconnect
the
ampli-
fier
From
the
power
Itne
and
dlschargecopacltors
prior to
making any ....
I.tanc.
check
or
N1movlng
the
EL84
output
tubes:.
Do not tum the
ampllfl.r
on wIth anyof the output
tubes
removea.
CHECKING
A
TYPICAL
TIJ8I
STAGI
I.
Check
tUbe.
2. Check plate andcathade
resl._.
3. Check- coupling capacttol'l for
leakage
or short.
4. For
output
stoge,
check
dc resistance of trGNformer
windings.
s.
Check
grid leak real.tor for
open.
6.
Check
cathode by-pau
capoclton
For
short.
7.
IF
no or low 8+
voltage
on
tube,
check
decoupllng
path
for open or
defective
R14,
and
filter capacitor, C8
farthart.
8.
IF
wiring and
circuit
components Including the tube
check
O.
K. and B+
voltage
is excessive,
cheek
the
de-
coupling path for short or deFective R
14-
SERVICE
Iftrouble developes in your instrument whichyou can not
remedy )'OUrs.lf, write to our
service
de~nt
listing
011
possible indications
that
might
be
helpful. If desired
you
may return the Instrument to our factory where It will
be
placed
In operating conclltton for $5.00 plus the
cod
of ports replaced
due
to
their
being damaged in the course
of construction. NOTE: Before
retumlng
this unit,
be
sure on parts are securely mounted.
Attach
a tag to the
instrument, giving your home address and
the
trouble with
the unit. Pack very corefUlly in a
"",pc;ontdlner,
us-
ing sufficient packing material (cotton, shredded news-
paper, or excelsior), to make the
unit
cornpletelyimmov-
oble within the container. The original shipping carton
is satisfactory, providing
the
original inserts
are
used or
suFFicient packing moteriol inserted to
keep
the instru-
ment immovable. Ship by prepaid Railway Express,
iF
possible, to Electronic Instrument
Co.,
Inc.,
33-00
North-
em
8Ivd.,
long
Island
City
1,
New
York. Retum ship-
mentwlll bemode byexpress
collect.
Note
that
a carrier
cannot
be
held
liable For damages in transit iF packing
IN HIS
OPINION,
is InsufFicient.