Pantech PG-1400, Руководство по обслуживанию

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PG-1400 Service Manual
These passive components are adopted for PAM to operate in a stable output power.
B. ASM (Antenna Switch Module / built in LPF)
These filters pass through the signals of which frequency band of 880~915MHz,
1710MHz~1785MHz which is the transmit frequency of GSM, DCS system terminal, and it
suppresses other images and spurious frequencies when the terminal transmits GMSK
modulated frequencies.
C. Power AMP Module (PAM)
This device amplifies signals ahead of transmiting them through the antenna to provide a sufficient
RF power. It has amplification factor of 28dB and efficiency of about 49% typically in GSM900 band
and amplification of 20dB and efficiency of about 53% typically in DCS band.
4.2.5 VC-TCXO(Voltage Controlled Temperature Compensated Crystal Oscillator)
This is the mobile station’s reference frequency source. Its frequency is 26MHz, this signal is
applied to the XOUT Buffer in Si4210 and the XOUT Buffer provides the 13MHz system reference
clock.
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