1)
2l
3t
4l
RECEIVER
SECTION
Antenna Switching
circuit
The
signal
from the antenna
J301
isfed to L101 through the
low-
pass
filter
since
both
D301
and
D302 are OFF.
HF Amplrlret
The signal from L10l
is ampli{ied by
0101
,
and applied
to the
bandpassfilter
consisting of
L102, L103and
Ll04.
Mixer circuit
The
signal
is fed to Q102 to
be mixed with
oscillator
frequency
from
the
PLL, and the
lst lF of 10,695
i\AHz is derived
from L105.
FM lF Amplif
ier
The
lst
lF of 10.695
l\lHz isappliedto
FL'i01 crystal
filter,when
C8101 is ON, and amplified
by
0103. The signal
is
then
mixed
with the PLL standard oscillator
frequency oI 1O.24l\,4H2 at
1C101
to convert to the
2nd lF of 455
KHz
and
applied to FL-103
and
FL-104. ICl01 consists of
limiter amp,
quadrature
detector, active
filter
and squelch
circuit. The detected
AF singal
comes out
at
pin
I.
SSB
lF
Amplif
ier
'
The
lF irequency
of
10.695
l\,4H2 from L105
isfed to FL102
crystal filter, when
CR102 is ON, and
amplified by
4104, A2A4
and Q205.
The
signal
from the secondary
side of
L203 is detected
by CR205,2a6,2Oi
and 208 diode.
AF Amplif ier
The detect€d AF signal
is amplified by
1C103 via
RV101 audio
volume to drive the
loudspeaker.
Squelch
circuit
ln FM mode, the squ€lch
is controlled by
pin
2
of lci01 .
The
AGC
voltage is used to control the squ€lch
in
SSB.
In both cases,
squelch voltage is adjusted
by RV202 to
control 0105, 106
and
107 AF
amplif
ier lC's.
6)
7l
-
13
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