McIntosh C20 - Page 10

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I
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pHoNo
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J-TApE
XTAL
MAGNEIIC
.
XTAL
MAGNFTrc
CERAMIC
2-lOr'rv
lO'7Omv
CERAl,llC
2-l0uv
lo-7omv
2-'l0nv
The fir
s
t
group
is rrlarked
'r
XTAL-
CERAMIC
I
and ie to
be
us
e
d
with a
c
ons tant arnplitude
c
ar
-
tridge
such as a
cr
ystal,
ceramic,
or
frequency
rnodulated
device. The
imput
sensitivity
for
full
output
is
0.
I
volt. The
input te
rrnination is
a
?,20
rnrnf
capacitor
in
series with 47,
000 ohms.
This
arrangernent
allows the record
corrrpensator
switche s
to
be used
with
the
se type
s
of cartridge
s .
The
second
group
is
rnarked 'ilow'
'
or"Z to
l0
MV'f
and
is de
signed
to
be
us ed
with rnagnetic car
-
tridge
s having
an
output
of
le
s s than
I
0
MV.
The
input
s
ens
itivity
f or f ull output
i s
Z
MV. The
in-
put
impedance
is
47,000 ohrns.
The
third
group
is rnarked
"High'r
or
'f
I0
to 70
MV"
to
be us ed
with
rnagnetic cartridge
s having
relatively
high output. The
input
sensitivity for
f ull
output is
l0
MV. Maximurn
inpr"t
voltage for
this
input
is 7
0
MV. The
input
impedance is
47
,
00 0 ohrns
.
If
a
cartridge
reguires other than
47,000
ohrns load irnpedance,
a re sistance
can
be added
acros
s
the
terrninals
of the cartridge to
achieve
the
correct
terrnination.
The following chart
rnay
be
used
as a guide:
Desired Irnpedance:
47,000
ohrns
(47K1
37,000
ohrns
(37K)
?,7
,000
ohrns
(Z7Kl
I
5,000
ohms
(
I
5K)
6,800
ohrns
(6.8K)
Resistor
Across Input:
No
Resistor
180,000
ohrns
(I80K)
62,
000
ohrns
(62K1
ZZ,00O
ohrns
(ZZKI
8,200 ohms
(8.2K)
Each
phono input
has
been
arranged
to
play
either stereo or rrronophonic.
In
the rnonophonic
position of the input
selector switch the two channels
of a stereo
cartridge
are
in paralleI
to
cancel
all vertical output. Vertical
output
results in objectionable noise
generated
when play-
ing
a rnonophonic recording
with a stereo cartridge.
If both
a 6tereo and
a
monophonic cartridge
are to be used
in the system, the
stereo
car-
tridge
can be
plugged into Phono
1 and the rnonophonic cartridge
into Phono
2,
either
left
'or
right
channel.
When
listening to the monophonic
cartridge turn the
selector switchto
Phono
2M
to
reproduce the
prograrn frorn both
speakers.
Not
that the
sarne
effect
could be achieved
by switching the
rnode selector to M
left or M right depending
on the channel used.
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