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SERVICEMANUAL

Published in July 992AN70761Revision 1

LDC-850

LDC-870

LDC-850

LDC-870

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Service

M anual

LDC-850

LDC-870

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CAUTION : DANGER OF EXPLOSION IF BATTERY IS INCORRECTLY RE-PLACED. REPLACE ONLY WITH THE SAME OR EQUIVALENT TYPE REC-OMMENDED BY THE MANUFACTURER. DISPOSE OF USED BATTERIESACCORDING TO THE MANUFACTURER'S INSTRUCTIONS.

CAUTION : DOUBLE-POLE / NEUTRAL FUSING

ATTENTION : IL Y A DANGER D'EXPLOSION S'IL Y A REMPLACEMENT IN-CORRECT DE LA BATTERIE. REMPLACER UNIQUEMENT AVEC UNEBATTERIE DU MME TYPE OU D'UN TYPE RECOMMAND PAR LECONSTRUCTEUR. METTRE AU RBUT LES BATTERIE USAGESCONFORMMENT AUX INSTRUCTIONS DU FABRICANT.

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Safety Precautions

This booklet provides safety warnings and precautions for our service

personnel to ensure the safety of their customers, their machines as wellas themselves during maintenance activities. Service personnel areadvised to read this booklet carefully to familiarize themselves with thewarnings and precautions described here before engaging inmaintenance activities.

R

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Safety warnings and precautions

Various symbols are used to protect our service personnel and

customers from physical danger and to prevent damage to their

property. These symbols are described below:

DANGER : High risk of serious bodily injury or death may result frominsufficient attention to or incorrect compliance with warningmessages using this symbol.

WARNING : Serious bodily injury or death may result from insufficient

attention to or incorrect compliance with warning messagesusing this symbol.

CAUTION : Bodily injury or damage to property may result frominsufficient attention to or incorrect compliance with warningmessages using this symbol.

Symbols

The triangle ( ) symbol indicates a warning including dangerand caution. The specific point of attention is shown insidethe symbol.

General warning.

Warning of risk of electric shock.

Warning of high temperature.

indicates a prohibited action. The specific prohibition isshown inside the symbol.

General prohibited action.

Disassembly prohibited.

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indicates that action is required. The specific actionrequired is shown inside the symbol.

General action required.

Remove the power plug from the wall outlet.

Always ground the copier.

1. Installation Precautions

WARNING

Do not use a power supply with a voltage other than that specified.Avoid multiple connections to one outlet: they may cause fire or electricshock. When using an extension cable, always check that it isadequate for the rated current. ...............................................................

Connect the ground wire to a suitable grounding point. Not groundingthe copier may cause fire or electric shock. Connecting the earth wireto an object not approved for the purpose may cause explosion orelectric shock. Never connect the ground cable to any of the following:gas pipes, lightning rods, ground cables for telephone lines and waterpipes or faucets not approved by the proper authorities.........................

CAUTION:

Do not place the copier on an infirm or angled surface: the copier maytip over, causing injury. ...........................................................................

Do not install the copier in a humid or dusty place. This may cause fireor electric shock. .....................................................................................

Do not install the copier near a radiator, heater, other heat source or

near flammable material. This may cause fire. .......................................

Allow sufficient space around the copier to allow the ventilation grills tokeep the machine as cool as possible. Insufficient ventilation maycause heat buildup and poor copying performance. ...............................

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Always handle the machine by the correct locations when moving it. ....

Always use anti-toppling and locking devices on copiers so equipped.Failure to do this may cause the copier to move unexpectedly ortopple, leading to injury. ..........................................................................

Avoid inhaling toner or developer excessively. Protect the eyes. If toneror developer is accidentally ingested, drink a lot of water to dilute it inthe stomach and obtain medical attention immediately. If it gets into theeyes, rinse immediately with copious amounts of water and obtainmedical attention. ....................................................................................

Advice customers that they must always follow the safety warnings andprecautions in the copiers instruction handbook. ...................................

2. Precautions for Maintenance

WARNING

Always remove the power plug from the wall outlet before startingmachine disassembly. ............................................................................

Always follow the procedures for maintenance described in the servicemanual and other related brochures. ......................................................

Under no circumstances attempt to bypass or disable safety featuresincluding safety mechanisms and protective circuits. .............................

Always use parts having the correct specifications. ...............................

Always use the thermostat or thermal fuse specified in the servicemanual or other related brochure when replacing them. Using a pieceof wire, for example, could lead to fire or other serious accident............

When the service manual or other serious brochure specifies a

distance or gap for installation of a part, always use the correct scaleand measure carefully. ...........................................................................

Always check that the copier is correctly connected to an outlet with aground connection. .................................................................................

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Check that the power cable covering is free of damage. Check that thepower plug is dust-free. If it is dirty, clean it to remove the risk of fire orelectric shock. .........................................................................................

Never attempt to disassemble the optical unit in machines using lasers.Leaking laser light may damage eyesight...............................................

Handle the charger sections with care. They are charged to highpotentials and may cause electric shock if handled improperly. .............

CAUTION

Wear safe clothing. If wearing loose clothing or accessories such asties, make sure they are safely secured so they will not be caught inrotating sections. .....................................................................................

Use utmost caution when working on a powered machine. Keep awayfrom chains and belts..............................................................................

Handle the fixing section with care to avoid burns as it can beextremely hot. .........................................................................................

Check that the fixing unit thermistor, heat and press rollers are clean.Dirt on them can cause abnormally high temperatures. .........................

Do not remove the ozone filter, if any, from the copier except forroutine replacement. ...............................................................................

Do not pull on the AC power cord or connector wires on high-voltagecomponents when removing them; always hold the plug itself. ..............

Do not route the power cable where it may be stood on or trapped. Ifnecessary, protect it with a cable cover or other appropriate item. ........

Treat the ends of the wire carefully when installing a new charger wireto avoid electric leaks. ............................................................................

Remove toner completely from electronic components. .........................

Run wire harnesses carefully so that wires will not be trapped ordamaged. ................................................................................................

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After maintenance, always check that all the parts, screws, connectorsand wires that were removed, have been refitted correctly. Specialattention should be paid to any forgotten connector, trapped wire andmissing screws. ......................................................................................

Check that all the caution labels that should be present on the machineaccording to the instruction handbook are clean and not peeling.Replace with new ones if necessary. ......................................................

Handle greases and solvents with care by following the instructionsbelow: ..................................................................................................... Use only a small amount of solvent at a time, being careful not to

spill. Wipe spills off completely.

Ventilate the room well while using grease or solvents. Allow applied solvents to evaporate completely before refitting the

covers or turning the main switch on. Always wash hands afterwards.

Never dispose of toner or toner bottles in fire. Toner may causesparks when exposed directly to fire in a furnace, etc. .........................

Should smoke be seen coming from the copier, remove the power

plug from the wall outlet immediately. ..................................................

3. Miscellaneous

WARNING

Never attempt to heat the drum or expose it to any organic solvents

such as alcohol, other than the specified refiner; it may generate toxicgas. .........................................................................................................

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CONTENTS

I THEORY AND CONSTRUCTION SECTION

1-1 Specifications1-1-1 Specifications ................................................................................ 1-1-1

1-2 Handling Precautions1-2-1 Consumables ................................................................................ 1-2-11-2-2 Precaution for Operation ............................................................... 1-2-11-2-3 Document ...................................................................................... 1-2-21-2-4 Paper ............................................................................................. 1-2-3

1-3 Mechanical Construction1-3-1 Names of machine parts and their functions ................................. 1-3-11-3-2 Machine cross section ................................................................... 1-3-6

1-3-3 Drive system ................................................................................. 1-3-71-3-4 Mechanical construction .............................................................. 1-3-11

II ELECTRICAL SECTION2-1 Electrical Parts Layout

2-1-1 Layout of electrical parts ............................................................... 2-1-12-2 Detection of Paper Misfeed

2-2-1 Paper jam detection ...................................................................... 2-2-12-2-2 Paper jam detection conditions ..................................................... 2-2-2

2-3 Operation of the PCBs

2-3-1 Configuration of electrical circuits ................................................. 2-3-12-3-2 Power source PCB ........................................................................ 2-3-22-3-3 Control PCB .................................................................................. 2-3-32-3-4 Network control unit PCB .............................................................. 2-3-42-3-5 Operation unit PCB ....................................................................... 2-3-5

III SET UP AND ADJUSTMENT SECTION3-1 Installation

3-1-1 Unpacking and installation ............................................................ 3-1-13-1-2 Setting and registering data ........................................................ 3-1-143-1-3 Installing the RS-232C board (Option) ........................................ 3-1-173-1-4 Installing the GDI (Printer) board (Option) .................................. 3-1-203-1-5 Installing the Dual line kit (Option) .............................................. 3-1-233-1-6 Memory (memory board) expansion ........................................... 3-1-32

3-2 Maintenance Mode3-2-1 Outline of service mode and test mode......................................... 3-2-13-2-2 Service mode ................................................................................ 3-2-23-2-3 Test mode ................................................................................... 3-2-47

3-3 Assembly and Disassembly3-3-1 Precautions for assembly and disassembly .................................. 3-3-13-3-2 Outer covers .................................................................................. 3-3-23-3-3 Paper feed section ........................................................................ 3-3-53-3-4 Document feed/image reading sections (ADF) ........................... 3-3-133-3-5 Optical section ............................................................................. 3-3-233-3-6 Fixing section .............................................................................. 3-3-243-3-7 Eject section ................................................................................ 3-3-32

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CONTENTS

1-1 Specifications

1-1-1 Specifications ...................................................................................... 1-1-1

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1-1-1

1-1-1 Specifications

Type ............................................... Desktop transceiverPower source ................................. 120 V AC, 60 Hz, 5.4 A

Power consumption ....................... Rated: Approx. 700 W (120 V AC)In the auto shut-off mode: 30 W or less (120 V AC)Dimensions .................................... 425 mm (W) 505 mm (D) 436 mm (H)

163/4" (W) 197/8" (D) 173/16" (H)Weight ............................................ 21 kg (463/16lbs)Option ............................................ Handset, Paper feed unit, Memory board (2 MB,

4 MB, 8 MB), GDI board, RS-232C board,Dual line kit

Facsimile function

Applicable line ................................ Subscription telephone lineCompatibility .................................. Group 3 (standard modem speed 14400 model)Super Group 3 (standard modem speed 33600

model)

Communication system .................. Half-duplexModulation ..................................... TCM, QAM, PhMEncoding system ............................ MMR, MR, MH (standard modem speed 14400

model)

MMR, MR, MH, JBIG (standard modem speed

33600 model)

Error Correction ............................. ITU-T ECMModem speed ................................ Standard modem speed 14400 model

14400/12000/9600/7200/4800/2400 (bps) (withautomatic fallback)

Standard modem speed 33600 model

33600/31200/28800/36400/24000/21600/19200/

16800/14400/12000/9600/7200/4800/2400 (bps)

(with automatic fallback)

Minimum transmission rate ............ Standard modem speed 14400 model10 ms/line (nomal mode), 5 ms/line (fine mode)

Standard modem speed 33600 model5 ms/line (nomal mode), 5 ms/line (fine mode)

Transmission time .......................... Standard modem speed 14400 modelApprox. 7 sec. (14400 bps, Memory transmission,MMR (ECM), ITU-T #1 chart)

Standard modem speed 33600 model

Approx. 3 sec. (33600 bps, Memory transmission,

JBIG (ECM), ITU-T #1 chart)

Memory capacity ............................ Standard modem speed 14400 model : 1.25 MB(standard)Standard modem speed 33600 model : 3.25 MB(standard)

Resolution mode ............................ Normal mode, Fine mode, Super fine mode, Halftone mode

Gray-scale ...................................... 64 levelsFeatures ......................................... Refer to Table 1-1-1 on page 1-1-2and Table 1-1-2

on page 1-1-2-1.

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1-1-2

Operation features One-touch dialing (45 destinations)Abbreviated number dialing (100 destinations)

Program dialing *1Group dialing *1Chain dialing (45 destinations)Auto redialingManual redialing *2Remote reception *2Auto FAX/TEL switching *2D.R.D. (Distinctive ring service) reception *2TAD reception *2Duplex fax transmission/reception

Standby transmissionPolling communication (Polling transmission, Pollingreception, Continuous polling reception)F-code based confidential transmissionF-code based relay broadcast transmissionAuto clear functionAuto shut-off function

Reliability features TTI transmission (Transmit Terminal Identifier)ECM communicationPassword check communication

Memory back-up (10min.)Encryption communicationRemote diagnosis

Report features Activity report Transmission reportReception report Restricted access reportDelayed communication report Confirmation reportUser setting list Confidential box reportRelay box report Encryption key listDepartment list

Memory features Memory receptionBroadcast transmission (145 destinations)F-code based confidential communication (10 confidentialboxes)Restricted Access (department code: 50)Dual accessBatch transmissionFax forwarding

Telephone features Directory

*1: It is possible to register under one-touch keys. Each of the 20 keys can bedesignated to function as either a program key or a group dial key.

*2: When the optional dual line kit is attached to the machine and two lines are used,those functions will be unavailable.

Table 1-1-1 (Standard modem speed 14400 model)

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1-1-2-1

Operation features One-touch dialing (70 destinations)

Abbreviated number dialing (170 destinations)

Program dialing *1Group dialing *1

Chain dialing (70 destinations)

Auto redialing

Manual redialing *2

Remote reception *2

Auto FAX/TEL switching *2

D.R.D. (Distinctive ring service) reception *2

TAD reception *2

Duplex fax transmission/reception

Standby transmissionPolling communication (Polling transmission, Polling

reception, Continuous polling reception)

F-code based confidential transmission

F-code based relay broadcast transmission

Auto clear function

Auto shut-off function

Reliability features TTI transmission (Transmit Terminal Identifier)

ECM communication

Password check communication

Memory back-up (10min.)Encryption communication

Remote diagnosis

Report features Activity report Transmission report

Reception report Restricted access report

Delayed communication report Confirmation report

User setting list Confidential box report

Relay box report Encryption key list

Department list

Memory features Memory reception

Broadcast transmission (200 destinations)

F-code based confidential communication (20 confidential

boxes)

Restricted Access (department code: 50)

Dual access

Batch transmission

Fax forwarding

Telephone features Directory

*1: It is possible to register under one-touch keys. Each of the 20 keys can be

designated to function as either a program key or a group dial key.

*2: When the optional dual line kit is attached to the machine and two lines are used,

those functions will be unavailable.

Table 1-1-2 (Standard modem speed 33600 model)

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This page is intentionally left blank.

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1-1-3

Copy functionCopy speed .................................... 8 sheets/min. (A4R/81/2" 11"R, equal

magnification)Resolution mode ............................ Normal mode, Fine mode, Super fine mode,

Half tone modeCopy mode ..................................... Sort copy, Group copyMagnification ratios ........................ In the normal mode, the fine mode, and the half-

tone mode; 50 - 200% (1% increments)In the super fine mode; 70-200% (1% increments)

Continuous copying ....................... 1 - 99 sheets

Document image reading section (ADF)Scanning system ............................ Flat bed scanning by the contact image sensorAuxiliary scanning line density ....... Horizontal/Vertical (600 600 dpi max.)

Normal (8 dots/mm

3.85 lines/mm)Fine (8 dots/mm 7.7 lines/mm)Super fine (8 dots/mm 15.4 lines/mm)

Document reading system ............. Document moving systemLight source ................................... LEDDocument set position ................... Width adjustable with the document centered on the

contact image sensorDocument feed ............................... Automatic feed

(Up to 50 documents (75 - 80g/m2) can be set atone time. However, paper of any thickness other

than 75 - 80g/m2

or paper of a size of smaller than51/2" - 41/2" should be fed one sheet at a time.)Document type ............................... SheetMaximum document size ............... A4R/81/2" 14"RDocument width ............................. 140 - 216 mm, 51/2" - 81/2"Document length ............................ 105 - 1000 mm, 41/8" - 393/8"Document thickness ....................... 50 - 160 g/m2

Paper type ...................................... Plain paper, Special paper (color paper, thermalpaper, art paper, letterhead) (Special paper shouldbe fed one sheet at a time.)

Effective scanning width ................ A4R: 202 mm or more, 81/2" 11"R: 208 mm ormore

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1-1-4

Printing sectionPrinting system .............................. Laser diode and electrophotographyWarm-up time ................................ 30 sec. or less (at 20C/68F, 65% RH)Paper feed system ......................... Automatic feeding from the paper cassette

Paper capacity ............................... Paper cassette: 500 sheets (75 - 80g/m2

)Paper size ...................................... A4R, Folio/81/2" 14"R, 81/211"RPaper type ...................................... Plain paper (75 - 80g/m2)Drum charging system ................... Single positive corona chargeExposure light source .................... Laser diodeScanning ........................................ Polygon mirrorPhotoconductor .............................. OPC (drum, 30 mm in diameter)Developing system ......................... Dry non-magnetic reverse developing

(1) Developer: Single-component(2) Toner replenishment: Toner cartridge

replacementImage transfer system ................... Transfer rollerSeparation system ......................... Curvature separationCleaning system ............................ Blade cleaningToner disposal system ................... Toner disposal tankCharge erasing system .................. Exposure by the cleaning lampFixing system ................................. Heat roller

(1) Heat source: Halogen heater (550 W: 120 V AC)(2) Control temperature: 185-170C/365-338F(3) Abnormally high temperature preventive

measure: 140C/284F (Thermostat)(4) Fixing pressure: 51 N (one side: 25.5 N)

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CONTENTS

1-2 Handling Precautions

1-2-1 Consumables ...................................................................................... 1-2-1(1) Paper ........................................................................................... 1-2-1(2) Imaging unit ................................................................................. 1-2-1(3) Toner cartridge ............................................................................ 1-2-1

1-2-2 Precaution for Operation ..................................................................... 1-2-11-2-3 Document ............................................................................................ 1-2-2

(1) Type of documents ...................................................................... 1-2-21-2-4 Paper .................................................................................................. 1-2-3

(1) Type of paper .............................................................................. 1-2-3

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1-2-1

1-2-1 Consumables

(1) Paper

Keep paper in a cool and dry place away from direct sunlight. If the machine is not

going to be used for a long period, remove the paper from the paper cassette and sealin the wrapping paper it was originally supplied in.

(2) Imaging unit

Keep the imaging unit in a cool and dry place away from direct sunlight. Always store ithorizontally. Storing it upside down or on its side may result in poor printing or leakingtoner.

(3) Toner cartridge

Keep the toner cartridge in a cool and dry place away from direct sunlight. Always store

it horizontally. Do not store it on its side.

1-2-2 Precaution for Operation

1. Do not open the machine while printing is in progress; it will cause a jam. 2. Attach the paper cassette correctly. A jam may otherwise occur. 3. Do not open the ADF cover while document reading is in progress; it will cause a

jam. 4. Adjust the position of the width guides to match the width of a document to be

used. A jam may otherwise occur.

5. Do not set documents of different sizes on the document table at one time. A jammay otherwise occur.

6. Replace the toner cartridge when the message of ADD TONER appears on themessage display to keep the printed image clean and clear.Once the toner cartridge is attached, do not remove it until the message of ADDTONER appears.

7. Replace the imaging unit when the message of REPLACE IU appears on themessage display to keep the printed image clean and clear.

8. Always keep the imaging unit horizontally. 9. While checking the laser scanning unit, PROTECT yourself from the laser, which

is invisible and cam harm the eyes.

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1-2-2

1-2-3 Document

(1) Types of documents

This machine can use the following types of documents

Type: Sheet Size: A4R, Folio/81/2" 14"R, 81/2" 11"R(Width: 140 mm - 216 mm, 51/2" - 81/2", Length: 128 mm - 1000 mm, 51/16" - 391/4")

Thickness: 50g/m2 - 160g/m2

Capacity: Up to 50 sheets(However, paper of any thickness other than 75 - 80 g/m2or paper of a size of smallerthan 51/2" - 41/2" should be fed one sheet at a time.)

Material: Plain paper, Special paper (color paper thermal paper, art paper, letterhead)(Special paper should be fed one sheet at a time.)

[Precautions] The areas within 10 mm from top and bottom or 4 mm from right and left sides of a

document may not be transmitted. The size of paper printed at a destination party may differ from that of paper which

was used for transmitting. When a document of a length of longer than the maximum length is set on the ADF,

this is treated as a document jam and DOCUMENT JAM appears on the messagedisplay.

Very low density characters may not be printed at a destination unit. Do not transmit hand-written or stamped documents until they are completely dry.

Remove clips and staples from documents before transmitting. (After removingstaples, fan documents to ensure they do not stick together.)

Documents that do not meet size and thickness requirements described above maynot be transmitted successfully.

Do not feed different-size documents through the ADF simultaneously or jams mayoccur.

If some documents are crinkled, bent, or curled, make those documents flat, and becareful to insert them.

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1-2-3

1-2-4 Paper

(1) Types of paper

This machine can use the following types of paper.

Size: A4R, Folio/81

/2" 14R, 81

/2" 11"R(Note that the size of paper which can be received with the facsimile is onlyA4R/81/2" 14"R and 81/2" 11"R.)

Thickness: 75g/m2 - 80g/m2

Material: Plain paper (75g/m2 - 80g/m2) Capacity: Up to 500 sheets

[Precautions]

Do not use the following paper; otherwise paper jams or machine problems may occur. Sheets with punched holes, perforations, tears, folds, or creases.

Damp or curled sheets. Sheets with staples or clips. Sheets that have already been passed through copiers or printers. Sheets with glue or adhesive on them.

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CONTENTS

1-3 Mechanical Construction

1-3-1 Parts names and their functions ......................................................... 1-3-1(1) Main body .................................................................................... 1-3-1(2) Operation panel (Standard modem speed 14400 model) ........... 1-3-3

(3) Operation panel (Standard modem speed 33600 model) ........ 1-3-5-1

1-3-2 Machine cross section ........................................................................ 1-3-61-3-3 Drive system ....................................................................................... 1-3-71-3-4 Mechanical construction ................................................................... 1-3-11

(1) Document feed/image reading sections (ADF) ......................... 1-3-11(2) Paper feed section ..................................................................... 1-3-13(3) Laser scanning unit .................................................................... 1-3-16(4) Imaging unit ............................................................................... 1-3-19(5) Transfer/charge erasing sections .............................................. 1-3-24(6) Fixing section ............................................................................ 1-3-25(7) Duplex/eject sections ................................................................ 1-3-27

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1-3-1

1-3-1 Names of machine parts and their functions

(1) Main body

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8

5

9

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Figure 1-3-1

1 Operation panel ...................... Use to operate the machine.2 Document table ....................... Set documents to be transmitted and copied here.3 Document guides .................... Adjust to match the width of documents.

4 ADF (Automatic Document Feeder)cover ....................................... Open when a document jams.

5 Main body release button ........ Press to open the machine.6 Document eject tray ................ Once ejected, documents are stacked on this tray.7 Paper eject table ..................... Once ejected, received faxes and copies are stacked

on this table.8 Paper eject table extensions ... Fold open when receiving faxes or making copies.9 Paper cassette ........................ Up to 500 sheets of plain paper (75 g/m2-

80 g/m2) can be set here.0 Cover plate.............................. One cover plate (Standard modem speed 14400

model) or two cover plates (Standard modem speed33600 model) are attached to the one-touch keys.

Flip the attached cover plate up or down in order toaccess the desired one-touch key number.

! Duplex unit .............................. Open if a paper jam occurs during print out of aDuplex fax reception or when making Duplex copies.

(Front view)

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1-3-2

%

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*

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#

(

)

Figure 1-3-2

@ Imaging unit ............................ This unit plays a major role in creating the image onreceived faxes and copies. When a message isdisplayed which tells you to replace the imaging unit,

replace the old unit with a new one.# Toner cartridge ........................ When a message telling you to replace the toner

cartridge is displayed, replace the old unit with a newone.

$ Toner cartridge release lever ... Use this lever when replacing the toner cartridge.% Fax moving handles ................ Hold these handles when moving the machine.^ Telephone jack ........................ Use this jack to connect a separately purchased

telephone.& Line jack .................................. Use this jack to connect the machine to a telephone

line with the supplied modular cord.

* Power receptacle .................... Connect the supplied power cord here.( Memory slot cover (M1) ........... Open this cover when the optional memory board is

installed.) Memory slot cover (M2) ........... Open this cover when the optional memory board is

installed while the optional dual line kit is installed.

(Rear view)

(Internal view)

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2AN-1

1-3-3

(2) Operation panel (Standard modem speed 14400 model)

1

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Copy/Space

Darker

Lighter

Half-Tone

Super Fine

Fine

TAD

Auto Rx.

Documentin Memory

Error

PC-On Line

Pause/Redial

Abbr./Directory

MemoryTx.

Clear/On-Hook

StopReset /

Send

Enter

A4 A4812 812

26 27 28 29 30

21 22 23 24 25

31 32 33 34 35

36 37 38 39 40

41 42 43 44 45

1 2 3 4 5

6 7 8 9 10

11 12 13 14 15

16 17 18 19 20

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Caps Lock

AlternateDisplay

PrintReports Duplex

DelayedTx. Function

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With the cover plate flipped down

Figure 1-3-3

1 Reset/Stop key ............ Press to stop operations in progress, revert to the initialmode, or eject documents from the ADF (AutomaticDocument Feeder).

2 Copy/Space key .......... Press in order to make copies or to change a character intoa space during input of the other partys name or faxnumber.

3 Send key ...................... Press to start fax transmission, manual fax reception orother operations.

4 Clear/On-Hook key ...... Press to dial without the need to pick up the telephonereceiver or to erase a registered fax number or other datawhen registering and canceling data under a given function.

5 On-Hook indicator ....... Lit when the Clear/On-Hook key has been pressed whilethe telephone receiver is still on the hook.

6 Pause/Redial key ......... Press to redial the last number dialed. Press also whileregistering a fax number under an abbreviated number orone-touch key in order to insert a pause of a few secondsat that point in dialing.

7 Abbr./Directory key ..... Press to dial with abbreviated numbers or to search thedirectory for names that are registered under abbreviatednumber.

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1-3-4

1

#

3DEF

5JKL

6MNO

4GHI

8TUV WXYZ

97PQRS

0OPER

*

2ABC

Copy/Space

Darker

Lighter

Half-Tone

Super Fine

Fine

TAD

Auto Rx.

Documentin Memory

Error

PC-On Line

Pause/Redial

Abbr./Directory

MemoryTx.

Clear/On-Hook

StopReset /

Send

Enter

A4 A4812 812

26 27 28 29 30

21 22 23 24 25

31 32 33 34 35

36 37 38 39 40

41 42 43 44 45

(

With the cover plate flipped up

Figure 1-3-4

8 Message display ................... Displays the present date, time, operationprocedures and trouble, etc.

9 Resolution select key ........... Press to select the degree of resolution most suitableto the documents being transmitted or copied.0 Resolution indicators ........... The uppermost indicator is for the Half-Tone mode,

the middle indicator is for the Super Fine mode, andthe lowermost indicator is for the Fine mode. Pressthe resolution select key to light the resolutionindicator corresponding to the desired mode. Whenall of the indicators are out, the machine is in theNormal mode.

! Reception mode select key ..... Press to select the desired reception mode.@ Reception mode indicators ..... The upper indicator is for the TAD reception mode.

The bottom indictor is for the auto fax reception mode.When using a separately purchased telephone withanswering machine capabilities in conjunction with themachine, press the reception mode select key until theTAD indicator light. When using the auto fax receptionmode, make sure the Auto Rx. indicator is lit. Whenusing the manual fax reception mode with aseparately purchased telephone connected to themachine, both indicators should be out.

# Function key .......................... Press to select one of the machines functions orregistration procedures.

$ Enter key ................................ Press during registration and setting procedures toregister the currently entered data under a givenfunction.

% PC-On line indicator ............. Lit when the machine is to be used as a printer orscanner.

^ Error indicator ....................... Lit when a communications error or mechanicalproblem has occurred.

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1-3-5

& Document inMemory indicator ........ Lit when there are documents stored in memory.

* Numeric keys ............... Use to enter fax numbers.* Even if your telephone service is for pulse dialing, press the

key after connecting to the other party and any keypressed on the key pad after that will transit the relatedtone signal.

( One-touch keys ........... Press to dial the fax number registered under the(No.1-45) corresponding one-touch key, as well as to enter one of the

characters marked under that key. Each of these keys canbe also designated to function as either a program key, a

group dial key or a chain dial key. Flip the cover platedown to access one-touch keys No.1-20, and flip it up toaccess one-touch keys No.21-45. When enteringcharacters, flip the cover plate down and press the one-touch key (No.1-15) marked with the desired character.One-touch key No.19 serves as the Caps Lock key.

) Memory Tx. indicator .. Lit in the Memory transmission mode. When this indicatoris out, the machine is in the Direct Feed transmissionmode.

Alternate Display key .. When carrying out 2 operations simultaneously (Dualaccess function), the display can be switched for theduration this key is held down to allow monitoring of thebackground operation currently in progress. If the Reset/

Stop key is pressed while this key is held down, it ispossible to cancel that background operation. Print Reports key ........ Press to print out a desired report or list. Delayed Tx. key ........... Press to perform procedures for communications which use

the timer. Memory Tx. key ........... Press to select between the Memory transmission and

Direct Feed transmission modes.fi Cursor keys (O) (P) ... Press to scroll through the message display and select the

desired function and/or setting. When entering characters,the (P) cursor key is also used to register the selected

character.fl Duplex key ................... Press this key when transmitting 2-sided documents ormaking Duplex (2-sided) copies.

Contrast select key ..... Press to select the level of contrast most suitable to thedocuments being transmitted or copied.

Contrast indicators ..... Press the contrast select key to light the contrast indicatorcorresponding to the desired mode. Make sure theDarker indicator is lit in order to increase the contrast oflighter documents and the Lighter indicator in order toreduce the contrast of darker documents. When both of the

indicators are out, the machine is in the Normal mode.

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1-3-5-1

(3) Operation panel (Standard modem speed 33600 model)

1

#

3DEF

5JKL

6MNO

4GHI

8TUV WXYZ

97PQRS

0OPER

*

2ABC

Copy/Space

Darker

Lighter

Half-Tone

Super Fine

Fine

TAD

Auto Rx.

Documentin Memory

Error

PC-On Line

Pause/Redial

Abbr./Directory

MemoryTx.

Clear/On-Hook

Reset /Stop

Send

Enter

A4 A4812 8

12

51 52 53 54 55

46 47 48 49 50

56 57 58 59 60

61 62 63 64 65

66 67 68 69 70

26 27 28 29 30

21 22 23 24 25

31 32 33 34 35

36 37 38 39 40

41 42 43 44 45

1 2 3 4 5

6 7 8 9 10

11 12 13 14 15

16 17 18 19 20

ABC DEF GHI JKL MNO

PQR ST UVW XYZ

Caps Lock

AlternateDisplay

PrintReports Duplex

DelayedTx. Function

* # 0~9@ /. : ( )&

? [ ] % ! =

%

@! 231)54 67

^& 90 8 * $ fi fl # (

With both cover plates down

Figure 1-3-4-1

1Reset/Stop key............ Press to stop operations in progress, revert to the initialmode, or eject documents from the ADF (Automatic

Document Feeder).

2Copy/Space key.......... Press in order to make copies or to change a character intoa space during input of the other partys name or fax

number.

3Send key...................... Press to start fax transmission, manual fax reception orother operations.

4Clear/On-Hook key...... Press to dial without the need to pick up the telephonereceiver or to erase a registered fax number or other data

when registering and canceling data under a given function.

5On-Hook indicator....... Lit when the Clear/On-Hook key has been pressed whilethe telephone receiver is still on the hook.

6Pause/Redial key......... Press to redial the last number dialed. Press also whileregistering a fax number under an abbreviated number or

one-touch key in order to insert a pause of a few seconds

at that point in dialing.

7Abbr./Directory key..... Press to dial with abbreviated numbers or to search thedirectory for names that are registered under abbreviated

number.

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1-3-5-2

Copy/Space

Pause/Redial

Abbr./Directory

MemoryTx.

Clear/On-Hook

Reset /Stop

Send

Enter

A4812

51 52 53 54 55

46 47 48 49 50

56 57 58 59 60

61 62 63 64 65

66 67 68 69 70

26 27 28 29 30

21 22 23 24 25

31 32 33 34 35

36 37 38 39 40

41 42 43 44 45

(

Copy/Space

Pause/Redial

Abbr./Directory

MemoryTx.

Clear/On-Hook

Reset /Stop

Send

Enter

A4812

51 52 53 54 55

46 47 48 49 50

56 57 58 59 60

61 62 63 64 65

66 67 68 69 70

(

With one cover plate up With both cover plates up

Figure 1-3-4-2

8Message display ................... Displays the present date, time, operationprocedures and trouble, etc.

9Resolution select key........... Press to select the degree of resolution most suitableto the documents being transmitted or copied.

0Resolution indicators........... The uppermost indicator is for the Half-Tone mode,the middle indicator is for the Super Fine mode, andthe lowermost indicator is for the Fine mode. Pressthe resolution select key to light the resolutionindicator corresponding to the desired mode. Whenall of the indicators are out, the machine is in theNormal mode.

!Reception mode select key..... Press to select the desired reception mode.@Reception mode indicators..... The upper indicator is for the TAD reception mode.

The bottom indictor is for the auto fax reception mode.When using a separately purchased telephone withanswering machine capabilities in conjunction with themachine, press the reception mode select key until theTAD indicator light. When using the auto fax receptionmode, make sure the Auto Rx. indicator is lit. Whenusing the manual fax reception mode with aseparately purchased telephone connected to themachine, both indicators should be out.

#Function key.......................... Press to select one of the machines functions orregistration procedures.

$Enter key................................ Press during registration and setting procedures toregister the currently entered data under a givenfunction.

%PC-On line indicator ............. Lit when the machine is to be used as a printer orscanner.

^Error indicator....................... Lit when a communications error or mechanicalproblem has occurred.

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1-3-5-3

&Document inMemory indicator........ Lit when there are documents stored in memory.

*Numeric keys...............Use to enter fax numbers.* Even if your telephone service is for pulse dialing, press the

key after connecting to the other party and any key

pressed on the key pad after that will transit the related

tone signal.

(One-touch keys........... Press to dial the fax number registered under the(No.1-70) corresponding one-touch key, as well as to enter one of the

characters marked under that key. Each of these keys can

be also designated to function as either a program key, a

group dial key, or a chain dial key. Flip both cover plates

down to access one-touch keys No.1-20, flip the top plate

up to access one-touch keys No.21-45 and flip both plates

up to access one-touch keys No.46-70. When entering

characters, flip both cover plates down and press the one-

touch key (No.1-15) marked with the desired character.

One-touch key No.19 serves as the Caps Lock key.

)Memory Tx. indicator.. Lit in the Memory transmission mode. When this indicatoris out, the machine is in the Direct Feed transmission

mode.

Alternate Display key.. When carrying out 2 operations simultaneously (Dualaccess function), the display can be switched for the

duration this key is held down to allow monitoring of the

background operation currently in progress. If the Reset/Stop key is pressed while this key is held down, it is

possible to cancel that background operation.

Print Reports key........ Press to print out a desired report or list.Delayed Tx. key........... Press to perform procedures for communications which use

the timer.

Memory Tx. key........... Press to select between the Memory transmission andDirect Feed transmission modes.

fiCursor keys (O) (P)... Press to scroll through the message display and select thedesired function and/or setting. When entering characters,

the (P) cursor key is also used to register the selectedcharacter.

flDuplex key................... Press this key when transmitting 2-sided documents ormaking Duplex (2-sided) copies.

Contrast select key..... Press to select the level of contrast most suitable to thedocuments being transmitted or copied.

Contrast indicators..... Press the contrast select key to light the contrast indicator

corresponding to the desired mode. Make sure the

Darker indicator is lit in order to increase the contrast of

lighter documents and the Lighter indicator in order to

reduce the contrast of darker documents. When both of theindicators are out, the machine is in the Normal mode.

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1-3-6

1-3-2 Machine cross section

Paper conveying path

Laser beam path

Document conveying path

1

7

7

2

3 4

6

5

Figure 1-3-5 Machine cross section

1 Document feed/image reading sections (ADF) (Page 1-3-11)2 Paper feed section (Page 1-3-13)3 Laser scanning unit (Page 1-3-16)4 Imaging unit (Page 1-3-19)5 Transfer/charge erasing sections (Page 1-3-24)6 Fixing section (Page 1-3-25)7 Duplex/eject sections (Page 1-3-27)

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1-3-7

1-3-3 Drive system

) *&

( ^%

$

12

3

# @! 0

45

6 7

8

9

Figure 1-3-6 Drive system 1 (Printing section)

1 Main motor gear2 IU gear 138/273 Paper feed gear 54/30

4 Paper feed gear 52/305 Paper feed gear 416 Paper feed gear 307 Paper feed gear 468 Paper conveying roller gear9 Paper feed gear 310 Registration clutch gear

! Drum gear 62@ Drum drive gear# Idle gear 59

$ Paper feed drive gear% Fixing drive gear 46/16^ Fixing joint gear& Heat roller gear* Fixing gear 25/17( Developing gear 24) Middle roller gear 14/20

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1-3-8

@!09

8765

4

3

1

2

Figure 1-3-7 Drive system 2 (Duplex/eject sections)

1 Eject roller gear2 Developing spiral gear3 Feedshift drive gear 18/224 Idle gear 525 Eject drive gear 116/34

6 Duplex motor gear

7 Duplex gear 112/508 Idle gear 379 Idle gear 300 Duplex roller gear A! Idle gear 58

@ Duplex roller gear B

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1-3-9

#@ !0

98 7

65

4321

Figure 1-3-8 Drive system 3 (Document feed section (ADF)

1 ADF eject pulley 362 ADF paper conveying belt3 ADF motor gear4 ADF paper conveying pulley 36

5 ADF paper conveying gear 296 Idle gear 407 ADF forwarding gear

8 ADF paper feed gear 599 ADF paper feed gear 180 ADF paper conveying belt pulley! Idle gear 56

@ Idle gear 53/25# ADF paper conveying belt pulley

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1-3-10

234 7

8

90!

5

6

1 @

Figure 1-3-9 Drive system 4 (Imaging unit)

1 Drum flange left gear2 Spiral gear 133 Idle gear 134 Drum idle gear5 Coupling gear 336 Coupling gear 35/35

7 Agitation gear 358 Agitation idle gear9 Replenishment roller gear 160 Developing idle gear 14! Developing roller gear 14@ Drum drive gear (machine main body)

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1-3-11

1-3-4 Mechanical construction

(1) Document feed/image reading sections (ADF)

The document feed/image reading sections consist of the components shown in Figure

1-3-10. Those sections convey documents set on the document table to the contactimage sensor (CIS) and read the document images.When the document detection switch (DDSW) is turned on by placing documents on thedocument table, the ADF motor (ADFM) starts rotating, and the set documents are fedand stacked between the forwarding retainer and the ADF forwarding pulley for thestandby condition of sending faxes or making copies (ADF standby operation). Whenthe ADF standby operation is complete, the ADF motor (ADFM) stops rotating.Pressing the Send key or Copy/Space key makes the ADF motor (ADFM) start rotating,and starts feeding the set documents one by one in the direction of the arrow shown inFigure 1-3-11 by the ADF forwarding pulley, ADF paper feed roller, ADF paper

conveying roller, and ADF eject roller. The ADF pad prevents multiple documents frombeing fed at a time.The images of the fed documents are read by the contact image sensor (CIS) when thedocuments passed on it.

6

876 54 3 2 1

^

%$#@!09

Figure 1-3-10 Document feed/image reading sections

1 Document table2 ADF upper housing3 Forwarding retainer4 ADF pad5 Pad retainer6 ADF upper pulley7 CIS upper sheet8 CIS retainer

9 ADF eject roller0 Contact image sensor (CIS)! ADF timing switch (ADFTIMSW)@ ADF paper conveying roller# ADF paper feed roller$ Document detection switch (DDSW)% ADF forwarding pulley^ ADF lower housing

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1-3-12

DDSW

ADFTIMSW

CIS

ADFM

CPCB

CN5-15

CN5-12

CN5-1

~CN5-10

CN8-1

~CN8-6

Figure 1-3-11 Document feed/image reading sections block diagram

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1-3-13

(2) Paper feed section

The paper feed section consists of the components shown in Figure 1-3-12. Thismechanism conveys the paper set in the paper cassette into the imaging unit and thetransfer/charge erasing sections in sync with the timing of image writing.

@ !

09

87

65

4

3

2

1

Figure 1-3-12 Paper feed section

1 Paper cassette2 Cassette guide3 Paper switch (PSW)4 Paper feed roller5 Middle paper conveying roller

6 Middle paper conveying pulley

7 Paper feed turn over pulley8 Registration switch (RSW)9 Registration lower roller0 Registration upper roller! Transfer front guide plate

@ Transfer front guide

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1-3-14

CN2-7

CN2-5

CN2-2

CN4-5

CN7-1

~ CN7-6MM

CPCB

FCL

PSW

RSW

RCL

Figure 1-3-13 Paper feed section block diagram

Feeding paper

FCL

MM

RSW: ON PRINT signal: sent RSW: OFFMM: ON

RCL

RSW

460 ms

470 ms

20 ms

Approx. 430 ms

1000 ms

A B

CD

E

Timing chart 1-3-1 Feeding paper

A 460 ms after the laser scanning unit of the machine has entered into the readinessof writing images and the main motor (MM) has started rotating, the feed clutch(FCL) is turned on to rotate the paper feed roller, starting the primary paper feed.

B 470 ms after the leading edge of the fed paper has turned on the registration switch(RSW), the feed clutch (FCL) is turned off to complete the primary paper feed.

C 20 ms after the feed clutch (FCL) has been turned off, the registration clutch (RCL)

is turned on to rotate the registration upper and lower rollers, starting the secondarypaper feed.

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1-3-15

D Approximately 430 ms after the registration clutch (RCL) has been turned on, thePRINT signal is sent, starting the operation of printing images.

E 1000 ms after the trailing edge of the paper has passed and turned off the

registration switch (RSW), the registration clutch (RCL) is turned off to complete thepaper feed. The paper is subsequently conveyed into the developing, transfer, andfixing sections and the operation of printing images is completed.

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1-3-16

(3) Laser scanning unit

The laser scanning unit consists of the components shown in Figures 1-3-14 and 1-3-15.The laser scanning unit forms a static latent image on the drum surface by repeatedly

turning the laser on and off depending on the laser control signals (LD signals) sentfrom the control PCB.

12

3

4

5

6

89

0

!

@

7

Figure 1-3-14 Laser scanning unit (1)

1 Polygon motor control board2 Polygon mirror3 Polygon motor (PM)4 Mirror5 Lens6 Cylindrical correcting lens

7 Laser diode board (with BD sensor)8 Cylindrical lens9 Lens0 Mirror! BD sensor mirror@ Cover

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1-3-17

To drum

09

6

9

4

32

1

8

7

5

!

Figure 1-3-15 Laser scanning unit (2)

1 Laser diode: Generates the laser beam which forms a static latentimage on the drum.

2 Collimator lens: Collimates the diffused laser beam emitted form the laser

diode to convert it into a cylindrical beam.3 Cylindrical lens: Shapes the collimated laser beam to suit the printingresolution.

4 Mirror: Reflects the laser beam onto the polygon mirror.5 Polygon mirror: Six-facet mirror that rotates at approximately 11338 rpm

with each face reflecting the laser beam toward the drumfor one horizontal scan.

6 BD sensor mirror: Reflects the laser beam to the BD sensor to generate thehorizontal synchronous signal (HSYNC).

7 Cylindrical correcting lens: Corrects for the deviation of the laser beam reflected by

the BD sensor mirror to the BD sensor.8 BD sensor: Detects the beam reflected by the BD sensor mirror,

outputting a signal to the control PCB (CPCB) to providetiming for the horizontal synchronous signal (HSYNC).

9 Lens: Corrects for non-linearity of the laser beam scanningspeed on the drum surface, keeps the beam diameterconstant and corrects for the vertical alignment of thepolygon mirror to ensure that the focal plane of the laserbeam is on one plane as it moves.

0 Mirror: Reflects the laser beam onto the drum surface.

! Drum

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1-3-18

The dimensions of the laser beam are as shown in Figure 1-3-16.

100 m

80 m

Figure 1-3-16

Scanning in the horizontal direction is provided by the rotating polygon mirror, whilescanning in the vertical direction is provided by the rotating drum, forming a static latentimage on the drum.The static latent image of the letter A, for example, is formed on the drum surface asshown in Figure 1-3-17. Electrical charge is dissipated on the area of the drum surface

irradiated by the laser.The focal point of the laser beam is moved line by line, and adjacent lines slightlyoverlap each other.

Horizontal scanning

Vertical scanning

: laser beam is on

Figure 1-3-17

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1-3-20

Drum/cleaning sections

The drum/cleaning sections consist of the drum and the cleaning section shown inFigure 1-3-19.

123

45

Figure 1-3-19 Drum/cleaning sections (1)

2

1

Figure 1-3-20 Drum/cleaning sections (2)

Cleaning the drum

The drum is cleaned by the cleaning blade.The cleaning blade removes the residual toner from the drum surface after transfer.The residual toner removed by the cleaning blade is conveyed to the toner disposaltank by the rotating cleaning spiral.

1 Drum

2 Cleaning blade3 IU housing4 Cleaning spiral5 Housing lower blade

1 Toner conveying pipe2 Toner disposal box

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1-3-21

Main charger assembly

The main charger assembly consists of the components shown in Figure 1-3-21. Byapplying a high voltage (+DC) from the high voltage transformer PCB (HVTPCB) to thecharger wire (tungsten wire) of the main charger assembly, positive corona is

discharged and the drum OPC layer is positively charged.The charger grid is installed on the main charger assembly so that the drum becomescharged evenly by the charger wire.The main charger turns on and off in sync with the main motor (MM).

1

2

3

4

5

6

Figure 1-3-21 Main charger assembly

1 Main charger housing2 Charger cleaner3 Main charger pin

4 Charger grid5 Main charger spring6 Main charger (charger wire)

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1-3-22

Main charger

Drum

Developing rollerToner supplyroller

CPCB

CN13-2

CN13-4

CN6-2

CN1-2

CN1-4

MC/DB REM

DB1 CHG

CN13-5CN1-5DB2 CHG

CN13-6CN1-6LEAK

HVTPCB

TEDS

Figure 1-3-22 Imaging unit block diagram

Operation of the imaging unit

MM

ESW

DB1 CHG

DB2 CHG

MC/DB REM 2300 ms

200 ms

50 ms75 ms

50 ms

500 ms

400 ms

360 ms

OFF

Forward

MSYNC signal: sent ESW: OFF

A

B

CD

E

Timing chart 1-3-2 Operation of the imaging unit

A 300ms after the laser scanning unit of the machine has entered into the readiness ofwriting images and the MSYNC signal has been sent, developing bias changingsignal 1 (DB1 CHG) goes low. At this time, non-image area voltage 1 ( 200V) (thedeveloping bias voltage) is output.

B 360 ms after the main motor (MM) has started rotating, developing bias changingsignal 1 (DB1 CHG) goes high and the main charger/developing bias signal (MC/DBREM) goes low. During this time, the developing bias voltage is switched to non-image voltage 2 (0V) in order to switch between the non-image area and the imagearea.

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1-3-23

C 50 ms after the main charger/developing bias signal (MC/DB REM) has gone low,developing bias changing signal 2 (DB2 CHG) goes low. 50 ms after that,developing bias changing signal 1 (DB1 CHG) goes low, and the developing biasvoltage is switched into the image voltage (+400V).

D 2300 ms s after the paper has been ejected after print out and the eject switch(ESW) has been turned off, the main charger/developing bias signal (MC/DB REM)goes high. 400 ms after that, the main motor (MM) stops rotating and developingbias changing signal 1 (DB1 CHG) goes high.

E75 ms after the main motor (MM) has stopped rotating, developing bias changingsignal 2 (DB2 CHG) goes high.

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1-3-24

(5) Transfer/charge erasing sections

The transfer/charge erasing sections consist of the components shown in Figure 1-3-23.

Transfer roller

The transfer roller is installed under the drum and electrically transfers the toner imageson the drum surface to the paper.A high voltage ( DC) is applied to the transfer roller (conductive urethane rubber roller)so that the transfer roller becomes more negatively charged than the drum surface.The transfer roller thus transfers the toner on the drum surface to the paper.1028 ms after the registration clutch (RCL) has turned on, transfer charging starts(charging the transfer roller), and 168 ms after the registration clutch (RCL) has turnedoff, transfer charging stops.

Cleaning lamp

The cleaning lamp (CL) removes the residual charge from the drum surface by lightingthe drum and collects the residual toner on the drum surface after transfer and send itinto the imaging unit (developing section).The cleaning lamp (CL) turns on when the main motor (MM) turns on, and then it turnsoff when the main motor (MM) turns off.

2 3

1

Figure 1-3-23 Transfer/charge erasing sections

CN13-3 CN1-3

CN2-16

CPCB

HVTPCBTC1 REM

CN13-8 CN1-8TC2 REM

CL

Drum

Transfer roller

Figure 1-3-24 Transfer/charge erasing sections block diagram

1 Transfer roller2 Cleaning lamp3 Drum

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1-3-25

(6) Fixing section

The fixing section consists of the components shown in Figure 1-3-25.The fixing section uses heat and pressure to fuse the transferred toner image to thepaper. The heat roller is heated by the fixing heater (FH) located inside of the fixing

section. During printing, the heat roller temperature is controlled to be 165

C/329

F-166C/330.8F (From the power on to the end of the initial stabilization control: 185C/365F-186C/366.8F) by switching the fixing heater on/off depending on the heat rollersurface temperature detected by the fixing thermistor (TH). When printing ends, thefixing heater (FH) turns off.If the temperature rises abnormally high, the fixing thermistor (TH) detects thetemperature abnormality, and the power to the fixing heater (FH) is cut off by the fixingthermostat (FTH).The press roller is pressed against the heat roller by the press springs at both ends ofthe press roller. The pressure between the press roller and the heat roller is

approximately 51 N (25.5 N for one side).

Separating paper from the heat roller

There are two separation claws on the fixing housing. When paper passes the fixingsection, those claws prevent the paper from sticking to the heat roller and wrappingaround it. The separation claws are constantly pressed toward the heat roller by theseparation claw springs.

1 2 34 5

6

7

Figure 1-3-25 Fixing section

1 Fixing housing2 Fixing thermistor (TH)3 Fixing heater (FH)4 Heat roller5 Fixing thermostat (FTH)6 Separation claw7 Press roller

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1-3-26

AC input

Fixing heatercontrol circuit

CN3-7CN3-5

H LIVE H NEUTRAL

CN3-1

CN3-3

CN1-7

CN1-1

CN1-2

FTH FH

TH

CPCB

CN2-14

CN1-2

CN1-7H REM

FuseFuse

Fuse

HRY

PSPCB

PG

CN1-124V

Noisefilter

Figure 1-3-26 Fixing section block diagram

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1-3-27

(7) Duplex/eject sections

The duplex/eject sections consist of the components shown in Figure 1-3-27.Those sections switch the paper conveying path depending on the copy mode, ejecting

paper and conveying into the duplex section.After printing out on the back side of the paper, in the duplex copy mode, the paper isconveyed into the duplex section by the operation of the feedshift section. Theconveyed paper is turned over in the duplex section and is fed again for printing on thefront side of paper.

7

$

#@!0

6

5

43

29

1

%

8

Figure 1-3-27 Duplex/eject sections

1 Feedshift A roller2 Feedshift roller3 Eject switch (ESW)4 Feedshift switching guide5 Middle eject lower roller6 Feedshift guide plate7 Eject pulley8 Eject roller

9 Middle eject upper roller0 Reverse switch (REVSW)! Duplex guide@ Duplex B roller# Duplex pulley$ Duplex A roller% Duplex turn over guide

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CONTENTS

2-1 Electrical Parts Layout

2-1-1 Layout of electrical parts ..................................................................... 2-1-1

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4

7

6

11

5 8 9

10

12

1

Machine right side Machine inside Machine left side

Figure 2-1-2 Layout of electrical parts: switches and sensors

1. Document detection switch (DDSW) ........... Detects the presence of documents onthe document table.

2. ADF timing switch (ADFTIMSW) .................Detects paper jams in the ADF section. 3. Contact image sensor (CIS) ........................Reads document images. 4. Eject switch (ESW) ......................................Detects the timing of feedshifting, and

paper jams in the feedshift and eject

sections. 5. Fixing unit thermistor (TH) ...........................Detects the surface temperature of theheat roller.

6. Reverse switch (REVSW)............................ Detects paper jams in the duplex unit. 7. Duplex switch (DUPSW)..............................Detects the presence of the duplex unit. 8. Toner empty detection sensor (TEDS) ........Detects the presence of toner in the

imaging unit. 9. Safety switch (SSW) .................................... Breaks the safety circuit when the

machine is opened, and resets paperjam detection.

10. Toner cartridge detection switch .................. Detects the presence of a toner(TCDSW) cartridge.

11. Registration switch (RSW) ...........................Detects paper jams in the paper feedsection.

12. Paper switch (PSW) ....................................Detects paper in the paper cassette.

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4

3 6

52

7

1


Figure 2-1-3 Layout of electrical parts: motors, clutches, and solenoid

1. ADF motor (ADFM)......................................Drives the ADF section. 2. Duplex motor (DUPM) .................................Drives the duplex and eject sections. 3. Main motor (MM) .........................................Drives the printer sections. 4. Cooling fan motor (CFM) .............................Exhausts heat out of the machine

interior and the fixing section. 5. Registration clutch (RCL) ............................Controls the rotation of the registration

upper and lower rollers. 6. Feed clutch (FCL) ........................................Controls the rotation of the paper feedroller.

7. Feedshift solenoid (FSSOL) ........................Operates the feedshift switching guide.

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1

3

7

6

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Figure 2-1-4 Layout of electrical parts: other electrical parts

1. Laser scanning unit (LSU) Polygon motor (PM) ..................................Drives the polygon mirror. Laser diode (LD) ........................................ Generates laser beam.

2. Cleaning lamp (CL) ......................................Removes residual charge from thedrum surface.

3. Fixing heater (FH) ........................................Heats the heat roller.

4. Fixing thermostat (FTH) ...............................Prevents overheating in the fixingsection. (breaks the safety circuit of thefixing heater.)

5. Speaker (SP) ...............................................Sounds an alarm and monitors thetelephone.

6. Heater relay (HRY) ...................................... Turns off and on the AC power for thefixing heater.

7. Backup battery (BT) .....................................Protects memory data during the poweroff.

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CONTENTS

2-2 Detection of Paper Misfeed

2-2-1 Paper jam detection ............................................................................ 2-2-12-2-2 Paper jam detection conditions ........................................................... 2-2-2

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2-2-1 Paper jam detection

Paper jams are detected by on and off timing of the switches located on the paper ordocument conveying path of the machine.

When a paper jam occurs, pull out the paper cassette or open the machine to remove thejammed paper.When a document jam occurs, open the ADF cover to the removed jammed document.

In order to reset paper jam detection, open and close the machine (turning off and on thesafety switch).In order to reset document jam detection, open the ADF cover to remove the jammeddocument (turning off and on the document detection switch (DDSW) and the ADF timingswitch (ADFTIMSW)).

When the paper jam detection is reset, the error indicator goes out and the message on themessage display disappears.

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2-2-2

2-2-2 Paper jam detection conditions

ADFTIMSW

ESW

FSSOL

REVSW

FCL

RCL

RSW

Figure 2-2-1 Paper jam detection

Paper jam at power supply onWhen the power supply is on (the power plug is connected or the safety turns off and on),any of the registration switch (RSW), eject switch (ESW), reverse switch (REVSW) orADF timing switch (ADFTIMSW) turns on.

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Paper jams in the fixing, eject, and duplex sections (JAM C)1The eject switch (ESW) does not turn off in 5.85 s after the registration clutch (RCL)

has turned off.

RCL

ESW5.85 s

OFF

OFF

ON

ON

Timing chart 2-2-4

2 While the duplex motor (DUPM) rotates forward, the eject switch (ESW) does notturn off in required time B after the eject switch (ESW) has turned on.

ESWB

OFF

ON

Timing chart 2-2-5

3 While the duplex motor (DUPM) rotates backward, the eject switch (ESW) does

not turn on in 320 ms after the eject switch (ESW) has turned off.

ESW

320ms

OFF

ON

Timing chart 2-2-6

Paper size

A4R

FOLIO

8-1/2"11"

8-1/2"14"

Required time B

6.69 s

7.375 s

6.315 s

7.915 s

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4 While paper is conveyed to the duplex section, the reverse switch (REVSW) doesnot turn on in 1.5 s after the eject switch (ESW) has turned on.

ESW

REVSW

1.5 s

OFF

OFF

ON

ON

Timing chart 2-2-7

5 While paper is fed from the duplex section, the registration switch (RSW) does notturn on in 3 s after the reverse switch (REVSW) has turned on.

RSW

REVSW

3 s

OFF

OFF

ON

ON

Timing chart 2-2-8

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Paper size error (JAM F)1The registration switch (RSW) turns off within required time C after the registration

clutch (RCL) has turned on. (The length of paper is too short.)

RCL

RSWC

OFF

OFF

ON

ON

Timing chart 2-2-9

2 The registration switch (RSW) does not turn off in required time D after theregistration clutch (RCL) has turned on. (The length of paper is too long.)

RCL

RSWD

OFF

OFF

ON

ON

Timing chart 2-2-10

3 The registration switch (RSW) does not turn off in 5 s after the feed clutch (FCL)has turned on.

FCL

RSW5 s

OFF

OFF

ON

ON

Timing chart 2-2-11

Paper size

A4R

FOLIO

8-1/2"11"

8-1/2"14"

Required time C

5.44 s

6.07 s

5.03 s

6.59 s

Paper size

A4R

FOLIO

8-1/2"11"

8-1/2"14"

Required time D

6.07 s

6.695 s

5.65 s

7.21 s

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Paper jams in the document feed section (ADF)1A document of a length of longer than the specified length (set with Memory switch

No.51) has passed the document feed section (ADF).2 The ADF timing switch (ADFTIMSW) does not turn on in 10 s after the ADF motor

(ADFM) has started rotating.

ADFTIMSW

ADFM

10 s

OFF

OFF

ON

ON

Timing chart 2-2-12

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CONTENTS

2-3 Operation of the PCBs

2-3-1 Configuration of electrical circuits ....................................................... 2-3-12-3-2 Power source PCB.............................................................................. 2-3-22-3-3 Control PCB ........................................................................................ 2-3-3

(1) Standard modem speed 14400 model ......................................... 2-3-3

(2) Standard modem speed 33600 model ...................................... 2-3-3-1

2-3-4 Network control unit PCB .................................................................... 2-3-42-3-5 Operation unit PCB ............................................................................. 2-3-5

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2-3-1 Configuration of electrical circuits

HRY

DDSW

ADFTIMSW

TDDSWREVSW

PSWDUPSW

ESW

TEDS

RSW

TH

ADFMDUPM

MMCFM

RCLFCL

FSSOL

CL

SSW

AC input Power sourcePCB (PSPCB)

Operation unitPCB (OPPCB)

BT

SP

Memory board(OPTION)

GDI board

(OPTION)

RS-232C board

(OPTION)

Sub-FAX board(OPTION)

Paper feed unit PCB

(PFUPCB)(OPTION)

LINE

TEL

Modular PCB

(MODPCB)

Control PCB

(CPCB)

Network control

unit PCB

(NCUPCB)

Laser scanning

unit (LSU)

High voltage

transformer PCB(HVTPCB)

Contact image

sensor (CIS)

H

Figure 2-3-1 Electrical circuit block diagram

The electrical circuit of the machine consists of the power source PCB (PSPCB), the controlPCB (CPCB), the network control unit PCB (NCUPCB), the modular PCB (MODPCB), thehigh voltage transformer PCB (HVTPCB), the operation unit PCB (OPPCB), the laserscanning unit (LSU), the contact image sensor (CIS), the loads and the switches.

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2-3-2 Power source PCB

H REM

AC input

DC24 V

DC5 V

DC12 V

DC-12 V

Noise filter

SSW

DC power

source

circuit

Control

PCB

(CPCB)

Fixing heatercontrol circuit

Heater relay

(HRY)

FH

Figure 2-3-2 Power source PCB block diagram

The power source PCB consists of the components shown in Figure 2-3-2 and eachcircuit operates as follows;

Noise filter

The noise filter prevents high-frequency noise peculiar to the switching regulator fromescaping out of the machine via the AC line input and also protects the internal circuits fromthe adverse effects of external noise.

DC power source circuitThe DC power source circuit rectifies and smoothes the AC input through the noise filterand generates 24 V DC, 5 V DC, 12 V DC and -12 V DC outputs that are supplied to thecontrol PCB (CPCB) using the switching regulator circuit.

Fixing heater control circuitThe fixing heater control circuit turns on or off the AC voltage that is applied to the fixingheater (FH) according to the fixing heater control signal (HREM) from the control PCB(CPCB).

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2-3-3

2-3-3 Control PCB(1) Standard modem speed 14400 model

I/O1(IC20)

CPU(IC17)

I/O2

(IC5)

SPADFTIMSW

DDSW

MODEM IC(IC28)

FIP(IC19)

I/O3(IC3)

REVSWPSW

DUPSWTH

TEDS

TCDSW

ESW

RSW

FSSOL

CL

DUPMMMCFM

ADFM

FCLRCL

PFUFMPFUFCL

CDSW

PFUPSW

A

B

C

ABC

ABC


Contact imagesensor (CIS)

RS-232C

board (OPTION)

GDI board

(OPTION)


Memory board(OPTION)

Resetcircuit

(IC21)

ROM(IC31)

RAM(IC30,IC39)

Network controlunit PCB

(NCUPCB)

High voltagetransformerPCB (HVTPCB)

Laser scanningunit (LSU)

Paper feed unitPCB (PFUPCB)(OPTION)

Figure 2-3-3 Control PCB block diagram (Standard modem speed 14400 model)

The control PCB (Standard modem speed 14400 model) consists of the components shown

in Figure 2-3-3.

The CPU (IC17) on the control PCB, according to the program in the ROM (IC31), controlsthe overall machine, receives the signals from the ADF timing switch (ADFTIMSW), thedocument detection switch (DDSW), and the contact image sensor (CIS), controls the input/output of the operation unit PCB (OPPCB), outputs audio-frequency signals to the speaker(SP), and controls the input/output of the optional RS-232C board, GDI board, and sub-FAX

board. The CPU (IC17) also controls the input/output of the optional memory board, RS-232C board, GDI board, and sub-FAX board via I/O1 (IC20) and I/O2 (IC5). I/O2 (IC5)receives the signals from the toner empty detection sensor (TEDS), the toner cartridgedetection switch (TCDSW), the eject switch (ESW), and the registration switch (RSW), andcontrols the output of the feedshift solenoid (FSSOL) and the cleaning lamp (CL). I/O3 (IC3)receives the signals from the reverse switch (REVSW), the paper switch (PSW), the duplexswitch (DUPSW), and the fixing unit thermistor (TH), controls the drive of the duplex motor(DUPM), the main motor (MM), the ADF motor (ADFM), the cooling fan motor (CFM), theregistration clutch (RCL), the feed clutch (FCL), controls the outputs of the high voltagetransformer PCB (HVTPCB) and the laser scanning unit (LSU), and controls the drive of the

optional paper feed unit.The modem IC (IC28) emits and receives the image signals into and from the networkcontrol unit PCB (NCUPCB).

The FIP (IC19) conducts A/D conversion of the image signals from the contact image sensor(CIS), enlargement/reduction of the image data, and shading process.

The reset circuit (IC21) outputs reset signals to the CPU if there is a CPU error, when thepower is switched on, or when the power supply voltage drops.

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(2) Standard modem speed 33600 model

I/O1(IC22)

CPU

(IC18)

I/O2

(IC6)

SPADFTIMSW

DDSW

MODEM IC

(IC29)

FIP(IC20, 7)

I/O3

(IC3)

REVSW

PSWDUPSW

TH

TEDS

TCDSW

ESW

RSW

FSSOL

CL

DUPMMMCFM

ADFMFCLRCL

PFUFM

PFUFCL

CDSWPFUPSW

A

B

C

ABC

ABC


Contact imagesensor (CIS)

RS-232C

board (OPTION)

GDI board(OPTION)


Memory board

(OPTION)

Reset

circuit(IC21)

ROM(IC32)

RAM

(IC31, 38)

Network controlunit PCB(NCUPCB)

High voltagetransformerPCB (HVTPCB)

Laser scanningunit (LSU)

Paper feed unitPCB (PFUPCB)(OPTION)

Figure 2-3-3-1 Control PCB block diagram (Standard modem speed 33600 model)

The control PCB (Standard modem speed 33600 model) consists of the components shown

in Figure 2-3-3-1.

The CPU (IC18) on the control PCB, according to the program in the ROM (IC32), controls

the overall machine, receives the signals from the ADF timing switch (ADFTIMSW), the

document detection switch (DDSW), and the contact image sensor (CIS), controls the input/

output of the operation unit PCB (OPPCB), outputs audio-frequency signals to the speaker

(SP), and controls the input/output of the optional RS-232C board, GDI board, and sub-FAX

board. The CPU (IC18) also controls the input/output of the optional memory board, RS-

232C board, GDI board, and sub-FAX board via I/O1 (IC22) and I/O2 (IC6). I/O2 (IC6)

receives the signals from the toner empty detection sensor (TEDS), the toner cartridge

detection switch (TCDSW), the eject switch (ESW), and the registration switch (RSW), and

controls the output of the feedshift solenoid (FSSOL) and the cleaning lamp (CL). I/O3 (IC3)

receives the signals from the reverse switch (REVSW), the paper switch (PSW), the duplex

switch (DUPSW), and the fixing unit thermistor (TH), controls the drive of the duplex motor

(DUPM), the main motor (MM), the ADF motor (ADFM), the cooling fan motor (CFM), the

registration clutch (RCL), the feed clutch (FCL), controls the outputs of the high voltage

transformer PCB (HVTPCB) and the laser scanning unit (LSU), and controls the drive of the

optional paper feed unit.

The modem IC (IC29) emits and receives the image signals into and from the networkcontrol unit PCB (NCUPCB).

The FIP (IC20, 7) conducts A/D conversion of the image signals from the contact image

sensor (CIS), enlargement/reduction of the image data, and shading process.

The reset circuit (IC21) outputs reset signals to the CPU if there is a CPU error, when the

power is switched on, or when the power supply voltage drops.

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2-3-4 Network control unit PCB

LINE

TEL

Pulse dialgeneration circuit

Ringing sounddetection circuit

Polarity detectioncircuit

Line transformer/Analog switch

External telephoneconnection controlcircuit

Control PCB(CPCB)

Modem IC(IC28*1)(IC29*2)

Figure 2-3-4 Network control unit PCB block diagram

The network control unit PCB consists of the components shown in Figure 2-3-4 andeach of them operates as follows;

Polarity detection circuitThe polarity detection circuit detects the line polarity and outputs the data of the linepolarity to the control PCB (CPCB).

Line transformerThe line transformer forms a closed circuit with the line and do inputs/outputs of imagedata.

Analog switchThe analog switch outputs image data from the line to the control PCB (CPCB).

Pulse dial generation circuit The pulse dial generation circuit outputs dial pulses to the line according to the pulse dial control signals from the control PCB (CPCB).

Ringing sound detection circuitThe ringing sound detection circuit detects the ringing sound from the line and notifies thecontrol PCB (CPCB) that there is an incoming call.

External telephone connection control circuitThe external telephone connection control circuit controls the connection with the externaltelephone.

The network control unit PCB is controlled by the modem IC (IC28*1/IC29*2) on thecontrol PCB (CPCB).

*1: Standard modem speed 14400 model

*2: Standard modem speed 33600 model

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2-3-5

2-3-5 Operation unit PCB

CPU

(IC17*1)

(IC18*2) CPU

(IC1)

Control PCB(CPCB)

Keyboardinput circuit

LED lighting

circuit

LCD

Figure 2-3-5 Operation unit PCB block diagram

The operation unit PCB consists of the components shown in Figure 2-3-5.

The operation unit PCB consists of the keyboard input circuit, the LED lighting circuit, andthe liquid crystal display device LCD, which are controlled by the one-chip CPU (IC1).The CPU (IC1) on the operation unit PCB has programmable I/O terminals and a clockoscillation circuit, and controls the input of the keyboard, the lighting of the LED, and themessage display on the LCD according to the program stored in the CPU.The input data from the keyboard and the displayed data on the LED and LCD are outputand input as serial data in sync with the clock signal from the CPU (IC17*1/IC18*2) on thecontrol PCB (CPCB).

*1: Standard modem speed 14400 model*2: Standard modem speed 33600 model

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CONTENTS

3-1 Installation

3-1-1 Unpacking and installation .................................................................. 3-1-1(1) Installation environment .............................................................. 3-1-1(2) Installation procedure .................................................................. 3-1-2

3-1-2 Setting and registering dat