Eico HF-85 - Page 33

where
you
con enjoy
a
normal
volume
level
and
are act-
ually
listening.
When the
situation
requires
a very soft
level,
or
you are
simply
providing
background
music,
in-
sertion
of
loudness
compensation
(IN
position)
will
elimi-
nate
a thin
"tinny"
sound
quality
by
boosting
lower
boss
tones
to
a more
audible
level.
The
reason
we prefer
that
you limit the
use
of loudness
compensation
is thot
compen-
sation
tends to
create
the
impression
that
you are sitting
close
to
an orchestra
that
is playing
softly.
This
carries
over
to
what would
normally
be
loud
orchestral
passages
and
may
therefore
be grossly
contradictory
to
the
sense
of
the
music.
When
no
compensation
is used
for
soft
listen-
ing
levels,
it
seems
merely that
you are
sitting
at
a greater
distance
from the
orchestra,
but the
sense
of
the
music
is
not
disturbed
except
for the
loss
of
audibility
mainly
at
the
extreme
low
frequencies.
However,
many
people
pre-
fer
the
pleosure of
hearing
the full
frequency
range
even
at
very
low listening
levels
and
they
will
employ
loudness
compensation
more often.
LISTENING
TO
PHONOGRAPH:
Set
the
SELECTOR
switch to
PHONO if
you
have
a magnetic
cartridge
or a
ceramic
cartridge
with
adaptors
interposed
between
the
cartridge
outputs
and the
MAG.
PHONO
1
and
2
Inputs.
(The
RIAA
equalization
provided at
the PHONO
position
is now the
intemotionalstondard
In
the
recording
industry
for both
monophonic
and
stereophonic
records
and
is
olso
a very good
compromise
For the
most
importontof
the
older
monophonicrecording
characteristics.)
Set the
SELECTOR
switch
toAUX
A or
AUX B If
you are
using
a stereophonic
crystal
cartridge
(Ronette)
connected
to
either
AUX
A
or
AUX
B inputs.
To play
a stereophonic
record.
Initially
set
the
MODE switch
to
MONOPHONIC
PHONO
ond
balance
the two
channels
as
described
obove
in
"LEVEL
BALANCE
BETWEEN
CHANNELS".
When
this
Is done,
set the
MODE
switch
to one
of the
STEREOPHONIC
posi-
tions for
stereo
listening.
To
ploy a
monophonic
record,
the
procedure
Is
exactlythe
same,
only the
MODE switch
remains
set
at the
MONOPHONIC
PHONO position,
pro-
viding the
identical
signol in
both
channels
with
mixing
of
the
inputs for
vertical
rumble
cancellation.
If it
is
desired
to listen
to the
monophonic
record
on
one channel
alone,
set the
MODE
switch
to
the
CHECK
AMPLIFIER
1
orCHECK
AMPLIFIER
2
position
depending
on which
chan-
nel is
desired.
Note
that in the
latter
case
there
is no
mixing
of the
Inputs
and vertical
rumble
is
not
cancelled.
The useofthe
LOUDNESS
switch,
ond the
BASS
and TREBLE
controls,
is
described
above.
LISTENING
TO TAPE
DECK
(direct
connection
to tape
head):
Set the
SELECTOR
to
TAPE.
NARTB
tape
equali-
zation
is
provided
in both
channels
for
the tope
speed
selected
with the
TAPE switch
on
the front
panel.
One
position
Is for
7
1/2
Ips
tapes
and the
other for
3
3/4 ips
tq>es.
These
equalizations
are the
industry
standard
for
pre-recorded
stereophonic
and
monophonic
topes.
The
remainder
of
the
procedure
is the
same
os "Listening
to
Phonograph"
described
obove,
listening
TO
AMONOPHONIC
source
CONNECT-
ED
TO
AUXILIARY
Al,
AUXILIARY
fll,
TO
MONO-
PHONIC
AM
BROADCAST,
OR
TO
MONOPHONIC
FM
BROADCAST
: Set
the
SELECTOR
to
AUX
A, AUX
B,
AM-
FM,or
FM-MULTI.
respectively
and
the
MODE
switch
to
MONOPHONIC
TUNER,
AUX. Use
the
BASS
and
TREBLE
controls
as
described
previously.
LISTENINGTOA
STEREOPHONIC
SOURCECONNECT-
ED
TO
AUXILIARY
Al ond
A2,
AUXILIARY
Bl and
B2,
AM
and FM,
FM
ond
FM
MULTIPLEX:
Set the
SELECTOR
to AUX
A,
AUX
B,
AM-FM, or
FM-MULTI
respectively.
Set
the
MODE
switch
ot
STEREO
NORMAL
or
STEREO
REVERSE.
The
LEVEL,
BASS
ond TREBLE
controls
ore
set
os
described
previously.
MAKING
RECORDINGS:
Tape
recordings
may be
made
by
connecting
the
recorder
to the
TAPE
OUTPUT
jacks.
Pleose
note that
recordings
cannot
be
made
on tape
decks
unless those
decks
are
equipped
with
the
electronics
re-
quired for
recording.
maintenance
Your
preamplifier
should
require
little
service
except
for
normal
tube
repiocement.
To facilitate
servicing,
remediol
and
trouble-shooting
pro-
cedures
have been
provided
in the
TROUBLE
SHOOTING
CHART
that
follows.
VOLTAGE
andRESISTANCE
CHARTS
ore
also provided
os
an aid to
locating
defective
com-
ponents.
On the
schematic
diagram,
AC mid-frequency
(1 kc)voltage
sensitivities
are
shown
at
most of
the grids
for
full
2 volt
output in
order
to
permit
a careful,
stoge-
by-stoge
check
of the
operation.
TROUBLE-SHOOTING
PROCEDURES
Connect
the
leads from
the stereo
cartridge
and from
the
two
speakers
to the
amplifier.
These
connections
are made
os described
in the
section
"Electrical
Installation".
Set
the
SELECTOR
switch
at
PHONO
and
the
MODE
switch
at
STEREO
NORMAL
or
REVERSE.
Play
a known
high
quality
stereo
recording
on the
phonogroph.
if
there
is
no
oufout to the
speaker
or if the
output
is low or
audibly
distorted,
precede
to the
checks
for
those
symptoms.
If
there
is
excessive
hum
In the
output,
disconnect
the
phono
input
cable
from
the
amplifier
ond
short
the
phono input
jack
to chassis.
If
the
hum
disappears,
the
trouble
is not
In the
amplifier
but in the
phonograph
or in the
connection
to the
amplifier.
In
each case,
check
for the
trouble
in
the
amplifier
which
seems
defective.
If both
amplifiers
ore defective,
check the
power supply.
Each
channel
can
be dealt
with
separately
by
setting
the
MODE
switch
to
CHECK
AMPLIFIER
I or
2
as desired.
The
causeof
phonograph hum
maybe
a metal pick-up
arm
or motor
not
grounded to the
preompi
if ier chassis
(run these
ground leads directly
to the
preamplifier
chassis, not to