Tone Amplifier; Circuit Description - Sharp OPTONICA SM-3000H Service Manual

EQUALIZER AMP
R33! pess
LR IK
c319
IOOOPFG
C320
ICOOPFG
0018
310
R332
1K
cA
8
R318
22k
Figure 4
TONE AMPLIFIER
5 LJ
C312 C3i SO35-4
SP 1 /IGOV LR
C30
5P R330
Oo) 2.7K IW
TUS '
CIRCUIT DESCRIPTION
Passing through
C301 and R303,
the output of cartridge enters
Notes:
VR301A
C439LR
+ 35/25V
56K
4 IN . me | 437] 8447
< i ; LR] + age 47OP] 220
+ meas
R430
Phe NY ett atts
O f) () 6033 T aet|
t) es .
To eeB oer | | el
E lawaoz
: PBE 4 |
R444
ue 470K
1
(
R407 Pos-6U
22K
R401
270P
c440 33s
425V
Figure 6
CIRCUIT DESCRIPTION
FILTER CIRCUIT
There are two type of filter circuit, one; 7kHz, —6 dB/oct.
and another; 30 Hz, —12 dB/oct.
CIRCUIT DESCRIPTION
The high cut
filter consists
of R461 and C450, and
the cutoff
frequency
is 7kHz
and the attenuation,
6 dB/oct.
The low cut
filter is a filter of NF (including C443
and R449) type making
use of the emitter follower, and the cutoff frequency is 30 Hz and
the attenuation 12 dB/oct.