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KX-FT937LA-B
6.6.
Modem Section
6.6.1.
Function
The unit uses a 1 chip modem (IC5) that serves as an interface between the control section for FAX transmission and reception
and the telephone line. During a transmitting operation, the digital image signals are modulated and sent to the telephone line.
During a receiving operation, the analogue image signals which are received via the telephone line are demodulated and con-
verted into digital image signals. The communication format and procedures for FAX communication are standardized by ITU-T.
This 1 chip modem (IC5) has hardware which sends and detects all of the necessary signals for FAX communication (DTMF).
It can be controlled by writing commands from the CPU (IC1: inside ASIC) to the register in the modem (IC5).
This modem (IC5) also sends DTMF signals, generates a call tone (from the speaker), and detects a busy tone and dial tones.
Overview of Facsimile Communication Procedures (ITU-T Recommendation):
1.
ON CCITT (International Telegraph and Telephone Consultative Committee)
The No. XIV Group of CCITT, one of the four permanent organizations of the International Telecommunications Union (ITU),
investigates and make recommendations on international standards for facsimiles.
2.
Definition of Each Group
• Group I (G1)
Official A-4 size documents without using formats which reduce the band width of a signal are sent over telephone lines.Deter-
mined in 1968.
Transmission for about 6 minutes at a scanning line density of 3.85 lines/mm.
• Group II (G2)
Using reduction technology in the modulation/demodulation format, an A-4 size document is sent at an official scanning line den-
sity of 3.85 lines/mm for about 3 minutes.
Methods to suppress redundancy are not used.
Determined in 1976.
• Group III (G3)
Method of suppressing redundancy in the image signal prior to modulation is used. An A-4 size document is sent within about
one minute.
Determined in 1980.
• Group IV (G4)
Transmission is via the data network. A method is provided for suppressing redundancy in signals prior to transmission, and
error-free reception of transmission is possible.
The scope of these facsimile applications is not limited simply to transmission of written statements. Through symbiotic linkages
with other communication methods, it can be expected to expand to include integrated services.
Содержание KX-FT937LA-B
Страница 11: ...11 KX FT937LA B 6 Technical Descriptions 6 1 Connection Diagram ...
Страница 21: ...21 KX FT937LA B 6 4 2 Block Diagram ...
Страница 23: ...23 KX FT937LA B ...
Страница 35: ...35 KX FT937LA B b Redundancy Compression Process Coding Mode This unit uses one dimensional MH format ...
Страница 66: ...66 KX FT937LA B The unit is too hot Stop using the unit for a while and let the unit cool down ...
Страница 68: ...68 KX FT937LA B ...
Страница 69: ...69 KX FT937LA B CROSS REFERENCE Test Mode P 54 ...
Страница 70: ...70 KX FT937LA B CROSS REFERENCE Test Mode P 54 ...
Страница 71: ...71 KX FT937LA B CROSS REFERENCE Test Mode P 54 ...
Страница 72: ...72 KX FT937LA B CROSS REFERENCE Test Mode P 54 ...
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Страница 75: ...75 KX FT937LA B CROSS REFERENCE Test Mode P 54 ...
Страница 102: ...102 KX FT937LA B NG Wave pattern Note Refer to NG Example P 107 ...
Страница 104: ...104 KX FT937LA B I O and Pin No Diagram ...
Страница 106: ...106 KX FT937LA B ...
Страница 107: ...107 KX FT937LA B 12 5 5 3 NG Example ...
Страница 111: ...111 KX FT937LA B 12 5 7 2 Troubleshooting Flow Chart ...
Страница 115: ...115 KX FT937LA B 12 5 10 CIS Contact Image Sensor Section Refer to Scanning Block P 24 CROSS REFERENCE Test Mode P 54 ...
Страница 116: ...116 KX FT937LA B 12 5 11 Thermal Head Section Refer to Thermal Head P 22 ...
Страница 117: ...117 KX FT937LA B 13 Service Fixture Tools ...
Страница 120: ...120 KX FT937LA B 14 2 Disassembly Procedure 14 2 1 How to Remove the Paper Stacker ...
Страница 121: ...121 KX FT937LA B 14 2 2 How to Remove the Operation Panel Block ...
Страница 122: ...122 KX FT937LA B 14 2 3 How to Remove the Operation Board LCD and Platen Roller ...
Страница 123: ...123 KX FT937LA B 14 2 4 How to Remove the Separation Holder and Document Feed Support ...
Страница 124: ...124 KX FT937LA B 14 2 5 How to Remove the Image Sensor CIS and Feed Roller ...
Страница 125: ...125 KX FT937LA B 14 2 6 How to Remove the Cutter Unit ...
Страница 126: ...126 KX FT937LA B 14 2 7 How to Remove the Lock Lever and Thermal Head ...
Страница 127: ...127 KX FT937LA B 14 2 8 How to Remove the Bottom Frame ...
Страница 128: ...128 KX FT937LA B 14 2 9 How to Remove the Analog Board Digital Board Power Supply Board and Power Cord ...
Страница 130: ...130 KX FT937LA B 14 2 12 Installation Position of the Lead Wires ...
Страница 138: ...138 KX FT937LA B 15 2 3 4 Copying CROSS REFERENCE Sensor Section P 114 ...
Страница 142: ...142 KX FT937LA B 16 1 4 Power Supply Board ...
Страница 146: ...146 KX FT937LA B Refer to Analog Board Section P 108 ...
Страница 147: ...147 KX FT937LA B 16 3 Test Chart 16 3 1 ITU T No 1 Test Chart ...
Страница 148: ...148 KX FT937LA B 16 3 2 ITU T No 2 Test Chart ...
Страница 155: ...155 KX FT937LA B MEMO ...
Страница 165: ...165 KX FT937LA B 20 1 2 Upper Cabinet Section ...
Страница 166: ...166 KX FT937LA B 20 1 3 Lower Cabinet Section ...
Страница 167: ...167 KX FT937LA B 20 1 4 Gear Block Section ...
Страница 168: ...168 KX FT937LA B 20 1 5 Screws ...
Страница 169: ...169 KX FT937LA B 20 1 6 Accessories and Packing Materials ...