Bpf Unit - Icom IC-9100 Service Manual

1ST TX IF CIRCUITS
• HF BAND (RF-A UNIT)
The 1st TX IF signal from the 2nd TX IF circuits is passed
through the 1st TX IF filter (FI911) to remove unwanted
signals. The fi ltered signal is amplifi ed by the IF AMP (Q611),
and then applied to the 1st TX mixer (D651), through the LPF.
The 1st TX IF signal is mixed with the 1st TX LO signal from
the PLL UNIT, resulting in the TX signal (TX frequency itself).
• 1ST TX IF CIRCUITS (HF BAND)
RF-A UNIT
FI911
From the
64.455 MHz(BW=15 kHz)
2nd TX IF
Q611
circuits
XTAL IF
AMP
BPF
• VHF BAND (RF-B UNIT)
The 1st TX IF signal from the 2nd TX IF circuits is passed
through the tree-staged BPF (L361–L363, C362–C364) and
BPFs (L332, C333 and FI331) to remove unwanted signals,
and then and amplified by the 1st TX IF AMP (Q1521).
The amplifi ed signal is applied to the 1st TX mixer (Q1551,
Q1552). The 1st TX IF signal is mixed with the 1st TX LO
signal from the PLL UNIT, resulting in the TX signal (TX
frequency itself).
The converted TX signal is passed through the BPF (D1611,
D1612, L1611, L1612, C1612–C1615), and then applied to
the YGR AMP (IC1651). The amplifi ed TX signal is applied
to the PA-B UNIT, through the BPF (D1671, D1672, L1671,
L1672, C1672–C1675).
• 1ST TX IF CIRCUITS (VHF/UHF BAND)
VHF TX IF
V1Lo
PLL
From the 2nd
UHF TX IF
TX IF circuits
BPF
71.25 MHz
I C2582
U1Lo
PLL
LO
BPF BPF
AM P
Q811
LO
LPF LPF
AMP
64.485~ LPF
124.455 MHz
IC601 To the
BPF
circuits
IF
LPF LPF
AMP
D651
FI331 Q1521
XTAL IF
BPF
BPF AMP
10.85 MHz
10.85 MHz
Q1471
125.15~
163.15 MHz
LO
HPF LPF
AMP
Q2521
FI731
XTAL
IF
LPF
BPF
AMP
71.25 MHz
Q2471
LO
HPF LPF HPF
AMP
348.75~408.75MHz
The converted TX signal is passed through the LPF, and
amplifi ed by the AMP (IC601), and then applied to the BPF UNIT.
The TX signal from the 1st TX IF circuits is passed through an
LPF or one of BPFs, depending on the transmitting frequency,
to remove unwanted signals contained in the TX signal.
The filtered TX signal is amplified by the YGR AMP (BPF UNIT;
IC201), and then applied to the PA-A UNIT.
1.6-2.0 MHz
BPF
2.0-4.0 MHz
BPF
4.0-8.0 MHz
BPF
8.0-11.0 MHz
BPF
11.0-15.0 MHz
BPF
15.0-22.0 MHz
BPF
22.0-30.0 MHz
BPF
1st TX LO 50.0-54.0 MHz
BPF
30.0-50.0 MHz
54.0-60.0 MHz
BPF
HPF
0.03-1.6 MHz
LPF
• UHF BAND (RF-B UNIT)
The 1st TX IF signal from the 2nd TX IF circuits is passed
through the BPFs (L761–L763, C762–C764 and FI731) to
remove unwanted signals, and then and amplifi ed by the 1st
TX IF AMP (Q2521). The amplifi ed signal is applied to the 1st
TX mixer (D2551), through the LPF (L2551, C2551–C2553).
The 1st TX IF signal is mixed with the 1st TX LO signal from
the PLL UNIT, resulting in the TX signal (TX frequency itself).
The converted TX signal is passed through the HPF (L2611,
C2612, C2615, C2616) and passed through or by-pass
the BPF (FI2611, F2612), depending on the operating
frequency, and then applied to the YGR AMP (IC2651). The
amplified TX signal is passed through or by-pass the BPF
(FI2711), depending on the operating frequency, and then
applied to another YGR AMP (Q2801).
The amplifi ed TX signal is applied to the PA-B UNIT, through
the LPF (L2831, C2831–C2833).
Q1551/Q1552
RF-B UNIT
FI2611/FI2612
BPF
D2551
HPF
ATT
LPF
3 - 6

BPF UNIT

IC201
To the TX AMP circuits
YGR
BPF
AMP
I C1651
YGR
BP F BPF
AMP
FI2711
Q2801
I C2651 BPF
YGR YGR
LPF
AMP AMP
ATT
To TX AMPs
LPF