Panasonic KX-TCD430GC, Service Manual

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20.4.2. Receiver Block
The signal of 1.9 GHz band (1.881792 GHz ~ 1.897344 GHz) which is input from antenna is input
to IC3 as shown in
BLOCK DIAGRAM (BASE UNIT) ().
In IC3, the signal of 1.9 GHz band is demoduleted, and goes to IC2 as GAP (Generic Access P
rofile) standard DECT frames. It passes through the decoding section burst switch controller
where it separates out the frame information and performs de-encryption and de-scrambling as
required. It then goes to the DSP section where it is turned back into analog audio. This is
amplified by the analog front end, and goes to the TEL LINE Interface.
20.5. Metering Pulse Detection
In the talk mode, the metering pulse is transferred as follows;
- A R81 IC2 (AD2) [METERING PULSE]
- B R53 IC2 (AD3)
21. BLOCK DIAGRAM (HANDSET)
22. CIRCUIT OPERATION (HANDSET)
22.1. Outline
Handset consists of the following ICs as shown in BLOCK DIAGRAM (HANDSET) ().
- DECT BBIC (Base Band IC): IC1
- All data signals (forming/analyzing ACK or CMD signal)
- All interfaces (ex: Key, Detector Circuit, Charge, DC/DC Converter,
EEPROM, LCD)
- RF Module: IC3
- PLL Oscillator
- Detector
- Compress/Expander
- Amplifier for transmission and reception
- EEPROM: IC2
- Temporary operating parameters (for RF, etc.)
Note:
Refer to 33.
EEPROM LAYOUT (HANDSET) .
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