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3 - 2
• TX AMPLIFIER CIRCUITS
3-2 TRANSMITTER CIRCUITS
2ND TX IF CIRCUITS (RF-C and MAIN-B UNITs)
The 10.95 MHz 2nd TX IF signal from the MAIN-B UNIT
of IC-9100 is passed through the BPF (L401–L403, C401,
C403, C404) and BPF (FI451) and amplified by the IF
AMPs (Q501). The amplified 2nd TX IF signal is applied to
the MAIN-B UNIT.
The amplified 2nd TX IF signal from the RF-C UNIT is
amplified by the IF AMP (Q81), and then applied to the 2nd
TX IF mixer (D82), through the LPF (L82, L83, C80, C85–
C89), to be mixed with the 2nd TX LO signal from the PLL
circuits, resulting in the 243.95 M Hz 1st TX IF signal.
The 1st TX IF signals applied to the 1st TX IF circuits.
1ST TX IF CIRCUITS (MAIN-B UNIT)
The 1st TX IF signal from the 2nd TX IF circuits is passed
through the LPF (L121, L122, C121–C125), amplified by the
IF AMP (IC111), and then passed through the BPF (FI101).
The filtered 1st TX IF signal is applied to the 1st TX IF mixer
(IC131) to be mixed with the 1st TX LO signal from the PLL
circuits, resulting in the TX signal (TX frequency itself).
The TX signal is passed through the BPF (FI141) and LPF
(L141, L142, C142–C146), and then applied to the TX
amplifier circuits.
TX AMP CIRCUITS (MAIN-B UNIT)
The TX signal from the 1st TX IF circuits is applied to the
YGR AMP (IC141). The amplified TX signal is passed
through the BPF (FI1), and amplified by the pre-drive AMP
(Q36) and power AMP (IC21).
The amplified TX signal is passed through the TX/RX SW
(RL51), power detector circuit (D502, D503), and then
applied to the antenna connector (J1).
LPF
BPF
XTAL
10.95 MHz
FI451
IF
AMP
AMP
Q501
MAIN-B UNIT
D82
To the 1st
TX IF circuits
233 MHz
RF-C UNIT
From the MAIN-B
UNIT of IC-9100
Q81
2Lo
2nd TX IF
10.95MHz
LPF
BPF
IF
AMP
IC111
FI101
996.1-1076.1 MHz
1st TX IF
To the TX
AMP circuits
From the 2nd TX
IF circuits
243.95 MHz
IC131
1LO
DRV
PRE
BPF
FI141
BPF
FI1
LPF
LPF
YGR
AMP
PWR
AMP
PWR
DET
D503
IC141
D502
From the 1st TX
IF circuits
Q36
IC21
TX/RX SW
To the RX circuits
RL51
• 2ND TX IF CIRCUITS
• 1ST TX IF CIRCUITS