Yaesu FT-902DM, Инструкция по эксплуатации

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When
02 1 0 7
i s groun ded,
0 2 1 0 2 ( 2SA 73 3 )
turn s
O N ,
and t h e vol tage appeari n g a t t h e collector of
Q 2 1 0 2
is fed th rough
D
2
1
0
9
( 1 S 1 5 5 5 ) to
D 7 0 1
on PB-
I
7 06A to a c tiva te the CW carri er oscilla tor.
I n the SSB m o d e , the SSB carrier oscillator is
d isabled by reverse vol tage.
COM MON CI RCUITS
VFO UNIT ( PB- 1 440B-3 3 3 0 )
A
modified Col p i t ts-type oscilla tor is used to
generate a 5 . 0 - 5 . 5 MHz signal, producing a
5 00 kHz tuning range . The frequency is vari e d
b y
vc 8 0 1 ,
wh ich is geared to a precision-buil t
dial tuning mech anism. VC 8 0 1 consists of two
sec tion s. The sub-blades c ompensate for th e
capacitance v a ri a tion o f the main blades wh ich
may resul t from e x treme temperature change .
V aractor d iod e 08 0 1
( 1 S2236) is in series with
C 8 0 7 ,
and the combin ation o f the two is in p a rallel
with TC8 0 1 . By closing the C L A R I FIER swi tch,
the VFO frequency may be varied ± 2. 5 kHz with
the CLARI F I E R control on the front panel .
The oscillator output signal is fed through the
amplifier/buffer s tage
Q 8 0 2
( 2 SK 1 9GR) and
Q 8 0 3 ( 2SC3 72Y ) , and then passes through the
l ow-pass filter to the ou tput terminal.
XTAL UNIT (PB-2 1 65 )
Crystal oscill ator
0 1 3 0 1 - Q 1 3 1 2
(all 2SC 1 8 1 5Y )
produces a heterod yne sign al for the
PLL
(Phase
Locked Loop ) mixer. The oscillator frequency
i s selec ted by the BAND switch, and the ou tpu t
signal is fed through diode switch
D 1 3 0 1 - D 1 3 1 2
(all
1 S 1 5 5 5 )
to the PLL UNIT. The frequency
o f each crys tal is sh own in Table
I .
- 3 1 -
VCO UNIT (PB-2 1 66)
The VCO (Vol tage Controlled Oscillator) gen erates
a h e te rodyne signal which is 8 . 9 8 7 5 kHz h ighe r
than the operating frequency. The frequency i s
locked b y the voltage d e te c te d b y t h e
PLL
UNI T.
Q 1 2 0 1 - Q 1 2 1 0
(all
2SK 1 9B L)
oscilla te at the
frequency given in Table
I .
The frequency is
locked by varactor diodes
0 1 2 0 1 - D 1 2 · 1 0
(all
MV
1 04 )
,
which are con trolled by the VCV vol tage
supplied from the
PLL
UNIT. The oscillator ou t­
put signal is amplified by
Q 1 2 0 9 ( 3 SK40
M
)
and
fed to the buffer/ampl i fie r c onsisting o f Q1
2
1
o
and
Q
1 2 1 1
(both
2SC 1 81 5 Y ) .
The ou tput fro m
Q 1 2 1 0 i s fed to t h e transceiver mixer in t h e
RF
UNI T ; the output · from Q 1
2 1 1 is fed to the PLL
UNIT as
a
sa m p le signal.
BAND CRYS TAL
1 6 0 m X 1 J O !
8 0 m X 1 Jo2
4 0 m
X 1 J O J
3 0 m
X1 Jo•
2 0 m
X1 los
1 7 m
X 1 Jo6
1 5 m
X 1 Jo 1
1 2 m X 1 3os
I
O rn
A
X1 309
! O m B X 1 J ! O
! O m C
X1 J 1 1
! O m lJ
X 1 J 1 2
g
x c o
v c o
F r eq u e n c y
F r e q u e n c y
1 5 . 9 87 5 M H z
1 0 . 4 8 7 5 - 1 0 . 9 87 5 M H z
1 7 . 9 87 5 M H z
1 2 . 4 8 7 5 - 1 2 . 9 87 5 M H z
2 1 . 4 87 5 M H z
1 5 . 9 8 7 5 - 1 6 . 4 87 5 M H z
2 4 . 4 87 5 M H z 1 8 . 9 8 7 5 - 1 9 . 4 8 7 5 M H z
28 . 4 8 7 5 M H z 22 . 9 87 5 - 2 3 . 4 87 5 M H z
3 2 . 4 87 5 M H z
26 . 9 8 7 5 - 2 7 . 4 8 7 5 M H z
3 5 . 4 87 5 M H z 2 9 . 9 8 7 5 - 30 . 4 87 5 M H z
38 . 9 87 5 M H z
3 3 . 4 8 7 5 - 3 3 . 9 87 5 M H z
4 2 . 4 8 7 5 M H z
36 . 9 8 7 5 - 3 7 . 9 87 5 M H z
4 2 . 9 87 5 M H z
4 3 . 4 8 7 5 M H z
3 7 . 9 87 5 - 38 . 9 8 7 5 M H z
4 3 . 9 87 5 M H z
Table 1