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Part 2 : Transmitter
Fig.5:TRX -The TX IF Modulator W2013 (IC100)
TIF Filter
270MHz
To IC101
TR106
To IC102
TIF Filter
180MHz
The TX IF Modulator
The TX I & Q signals from IC27 #86-89 are fed to #4-7 of the W2013 TX
modulator (IC100), where they are then modulated onto either a TX IF of 270Mhz
(for GSM- TX) or 180Mhz (for PCN-TX) by the quadrature mixer inside IC100.
The signal TX LO IF (180-270Mhz) is input on #9 of IC100 (W2013) from (IC300)
#24. This signal is produced by the internal 540Mhz oscillator within IC300, which
has been divided down by a factor of 2 for GSM-TX or 3 for PCN-TX. This division
factor is set by the control signal GSM_TX from IC27 #23.
The TX modulated IF signal of 270Mhz is output on #2 of IC100 for GSM or a
modulated IF signal of 180Mhz is output on #3 of IC100 for PCN.
Pre-amp transistors TR106 and TR107 amplify the signal and then pass it through
to BPF's: FL100 or FL101 for filtering and then after to the RF Mixer's (IC101 or
IC102).
PMB2410 (IC300)
540Mhz Osc
3V_G_TX
9
2
GND
3V_P_TX
3
W2013
TR107
GND
32
Div2/3
180 - 270Mhz
5
TIPI
4
TINI
6
TQPI
7
TQNI
2v85_rf3
(1,16,20)
IF-PLL
GSM_TX
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