Samsung SCH-i830 Service Manual

Also see for SCH-i830 Series: User guide Phone guide Pocket guide User guide Service manual

SAMSUNG Proprietary-Contents may change without notice2-3-2. TransmitterAntenna(ANT1)Antenna(ANT1) sends signal to the base station and receives the signal from the base station.It is a multi-band Antenna and covers PCS band, CDMA band DCS band, GSM Tx band and GPS band.RF Switch(U1201)It(U1201) is used to switch the PCS path, the CDMA path the GPS path and the GSM path, The RFsignal pass through PCS path when PCS_SW is high.PCS_SW, CDMA_SW, GPS_SW and GSM_SW are digital signals from MSM6500 via Decoder(U1200).Duplexer(DUF1107)Duplexer(DUF1107) allows Rx frequency range(881.49 ±12.5 MHz) and Tx frequency range(836.49 ±12.5 MHz) from the antenna to pass through LNA. It also matches LNA input inreceiving part and PAM(PAM1104:CX77105) output in transmitter part with the antenna.Power Amp(PAM1104)Power amplifier module(PAM1104:CX77105) amplifies signal to be sent to the base stationthrough the antenna.RF Band Pass Filter(Tx RF SAW Filter)The RF BPF(F901) pass only specific frequency(836.49 ±12.5MHz) to send it to poweramp(U903:CX77105).Direct Conversion Transmitter(U1102)The Direct Conversion Transmitter(U1102: RTR6300) allows the signal to be inputted to thepower amp(PAM1103) as a specified level from I, Q base band signals.Automatic Gain Control AmpThe TX AGC amp in RTR6300 controls gain of AGC to deliver power level to be neededat Driver amp. Its control voltage varies from 0.2V to 2.5V.