Okidata fax 1000 schematic

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Service Guide OF1000

Chapter 0 About This Manual

OKIFAX 1000

Facsimile Product

Adobe Acrobat printable reference

copy of the OKIDATA Service Training Manual.

09/17/97

Note: This Adobe Acrobat version of the Okidata Service Training Manual was built with the

pictures rendered at 300 dpi, which is ideal for printing, but does not view on most displays well.

Table of Contents Page

Service Guide OF1000

0 About This Manual

Front Cover 1 Manual Copyright 2

1 Product Specifications

1.1.01 General Information 3

1.2 General Facsimile Specifications 4

1.3 Communications 5

1.4 Printer Specifications 6

1.5 User Functions 7

1.6 Scanner Specifications 8

1.7 Consumable Items 9

1.8 Options 10

1.9 Agency Approvals 11

1.10 Reliability Data 12

2 Principles of Operation

2.1 Principles Of Operation 13

....2.1.01 Compatibility 14

....2.1.02 Communications Mode 15

....2.1.03 Modem Operation 16

....2.1.04 Automatic Fall-Back Mode 17

....2.1.05 Telephone Line Connection 18

....2.1.06 Error Correction Mode (ECM) 19

....2.1.07 Major Assemblies 20

........Okifax 1000 Cross-Sectional View 21

........Copy Function Block Diagram 22

........Report Print Function Block Diagram 23

2.2 Transmitter Theory Of Operation - Typical Transmission 24

....300 bps Transmit Handshake Operation Diagram 25

....300 bps Receive Handshake Procedure Diagram 26

....G3 Transmit Functional Block Diagram 27

....2.2.02 Operator Panel 28

....2.2.03 Automatic Document Feeder (ADF) 29

....2.2.04 Scanner Assembly 30

....2.2.05 Encoder 31

....2.2.06 Modem 32

....2.2.07 Network Control Board (NCU) 33

....2.2.08 Line Board 34

2.3 Receiver Theory Of Operation 35

....G3 Receive Operation Block Diagram 36

2.4 LED Printer - Principal Components 37

....2.4.02 Printer Control Board (PCNT-150) 38

....2.4.03 Power Supply Board (PWU-150) 39

Table of Contents Page

........Power Supply Block Diagram 40

....2.4.04 Sub-Power Supply Board (PSUB-150) 41

........Sub-Power Supply Board Block Diagram 42

....2.4.05 Fuser Unit 43

....2.4.06 Main Motor (Drum Motor) 44

....2.4.07 LED Array 45

....2.4.08 DC Fan 46

....2.4.09 Registration Motor 47

2.5 Printing Process - General Information 48

........Printing Process Diagram 49

....2.5.02 Hopping 50

....2.5.03 Feeding 51

....2.5.04 Charging 52

....2.5.05 Exposing 53

....2.5.06 Developing 54

....2.5.07 Transfer 55

....2.5.08 Fusing 56

....2.5.09 Cleaning 57

....2.5.10 Printing 58

2.6 Sensors And Switches 59

....Sensor Location Diagram (Top View) 60

........Detail of Sensor / Lever 61

........Paper Inlet Jam 62

........Paper Feed Jam 63

....2.6.02 Toner Low Sensor 64

3 Maintenance & Disassembly

3.1 Maintenance - General Information 65

3.2 Disassembly/Assembly Procedures 66

....3.2.01 Preliminary Items 67

....3.2.02 LED Head 68

....3.2.03 Terminal Cover Cap, Rear Cover, and Fan 69

....3.2.04 Line Board (LINE-JU) 70

....3.2.05 Package Shelf Assembly 71

....3.2.06 Network Control Unit (NCU-U) 72

....3.2.07 Main Control Board (MCNT-150) 73

....3.2.08 Printer Control Board (PCNT-150) 74

....3.2.09 Left Side Cover 75

....3.2.10 Hook Switch Board (Hook-SW) 76

....3.2.11 Power Supply Unit (PWU) 77

....3.2.12 Gear Frame Assembly 78

....3.2.13 Transmit Stepper Motor 79

....3.2.14 Gear Frame and Gears 80

....3.2.15 Memory Card (Option) 81

....3.2.16 Right Side Cover 82

Table of Contents Page

....3.2.17 Document Guide Assembly 83

....3.2.18 Speaker 84

....3.2.19 Separation Rubber Assembly 85

....3.2.20 Control Panel Assembly 86

....3.2.21 Upper Paper Guide Assembly 87

....3.2.22 Upper Feed Roller Assembly 88

....3.2.23 Pinch Roller 89

....3.2.24 Sub Pinch Roller Guide Assembly 90

....3.2.25 Paper Table Guide 91

....3.2.26 Sensor Roller Assembly 92

....3.2.27 Sub Roller Assembly 93

....3.2.28 ADF Roller Assembly 94

....3.2.29 Pinch Roller 95

....3.2.30 Document Detect Assembly (PC1) 96

....3.2.31 Read Station Sensor Assembly (PC2) 97

....3.2.32 Exit Guide 98

....3.2.33 Lower Feed Roller Assembly 99

....3.2.34 Image Sensor Assembly 100

....3.2.35 ADF Idle Gear 101

....3.2.36 Scanner Frame Assembly 102

....3.2.37 Release Guide Assembly 103

....3.2.38 Second Tray Interface Board 104

....3.2.39 Registration and Main Stepper Motors 105

....3.2.40 Eject Roller Assembly 106

....3.2.41 Manual Feed Guide Assembly 107

....3.2.42 Face-Down Stacker Cover Assembly 108

....3.2.43 Fuser Unit Assembly 109

....3.2.44 Lower Base Assembly 110

....3.2.45 Reduction and Stepper Motor Idle Gears 111

....3.2.46 Reset Levers and Pressure Roller 112

....3.2.47 Transfer Roller 113

....3.2.48 Registration Roller 114

....3.2.49 Hopping Roller Assembly 115

....3.2.50 Inlet Sensor Plates 116

....3.2.51 Outlet Sensor Plate 117

....3.2.52 Toner Sensor Plate 118

....3.2.53 Contact Assembly and Sub-Power Supply Board

(PSUB)

....3.2.54 Left and Right Cassette Guides and Base Assembly 120

....3.2.55 Paper Supply and Cassette Sensor Plates 121

3.3 Adjustments And Service Settings 122

........LED Intensity Rating / Dip Switch Settings Table 123

3.4 Cleaning 124

3.5 Lubrication 125

119

Table of Contents Page

4 Failure & Repair Analysis

4.1 Failure & Repair Analysis - Introduction 126

4.2 Troubleshooting Updates 127

4.3 Reporting Problems 128

4.4 Troubleshooting Tips 129

4.5 Repair Analysis Procedures 130

....4.5.02 RAP Index 131

........RAP 01: No LCD Display 132

........RAP 02: Alarm LED is Lit 133

........RAP 03: Local Copy Problem 134

........RAP 04: Auto-Dial Problem 135

........RAP 05: Data Transmission Problem 136

........RAP 06: Auto Reception Problem 137

........RAP 07: Reception Problem 138

........RAP 08: Self-Diagnosis Failure 139

........RAP 09: Scan Operation Test Failure 140

........RAP 10: LED Test Failure 141

........RAP 11: Tone Test Failure 142

........RAP 12: High-Speed Modem Test Failure 143

........RAP 13: Multi-Frequency Tone Test Failure 144

........RAP 14: Printer Unit Print Test Failure 145

........RAP 15: Voice Message Test Failure 146

........RAP 16: No Acoustic Line Monitor 147

........RAP 17: Document Does Not Feed 148

........RAP 18: Multiple Documents Feed 149

........RAP 19: Document Skews 150

........RAP 20: Document Jams 151

........RAP 21: Printer Unit Problems Shown On LCD Display 152

............RAP 21A: Cover Open 153

............RAP 21B: Printer Alarm 1 154

............RAP 21C: Printer Alarm 2 155

............RAP 21D: Printer Alarm 3 156

............RAP 21E: Printer Alarm 4 157

............RAP 21F: Paper Jam - Confirm and Stop 158

............RAP 21G: No Paper 159

........RAP 22: Image Problems 160

............RAP 22A: Poor Print Quality (Images Light or Blurred

as a Whole)

............RAP 22B: Dark Background Density 162

............RAP 22C: Printed Output is Blank 163

............RAP 22D: Vertical Black Stripes on Printed Output 164

............RAP 22E: Repetitive Spaced Marks on Printed Output 165

............RAP 22F: Vertical White Streaks on Printed Output 166

............RAP 22G: Areas Missing From Printed Output 167

161

Table of Contents Page

............RAP 22H: Poor Fusing 168

4.6 Local Diagnostic Testing 169

....4.6.01 Self-Diagnosis 170

....4.6.02 Scan Operation Test / CIS Calibration 171

....4.6.03 LED Test 172

....4.6.04 Tone Test 173

....4.6.05 High-Speed Modem Transmit Test 174

....4.6.06 High-Speed Modem Receive Test 175

....4.6.07 Multi-Frequency Tone Test 176

....4.6.08 Printer Unit Print Test 177

....4.6.09 Voice Message Test 178

4.7 Reports - Activity Report 179

....Service Codes List 180

....4.7.02 Protocol Dump 181

........Sample Analysis of Protocol Dump Data 182

........Facsimile Control Field Conversion Table 183

4.8 Resets 184

....4.8.01 Toner Counter Reset 185

....4.8.02 Drum Counter Reset 186

....4.8.03 Fuser Counter Reset 187

4.9 Clearing The Random Access Memory (RAM) 188

....4.10 Accessing the Technical Function Settings 189

........Technical Function (TF) Listing 190

....4.11 Telephone Answering Device (TAD) Interface 191

A Reference Charts

General Information 192 A.2 Index To Charts 193

....A.2.01 Main Control Board (MCNT-150) 194

....A.2.02 Printer Control Board (PCNT-150) 195

....A.2.03 Power Supply Board (PWU-150) 196

....A.2.04 Network Control Unit (NCU-U) 197

....A.2.05 Line Board (LINE-JU) 198

....A.2.06 Hook Switch (HOOK -150) 199

....A.2.07 Operator Panel Board (OPE-150) 200

....A.2.08 Sub-Power Supply Board (PSUB- 150) 201

....A.2.09 Second Tray Interface Board 202

B Illustrated Parts Listing

General Information & Parts Overview Diagram 203

....B.1.02 Definition of Terms 204

....B.1.03 Parts Ordering Information 205

B.2 CHARTS 206

....B.2.01 Cabinet Assembly (1 of 2) 207

....B.2.02 Cabinet Assembly (2 of 2) 208

....B.2.03 Control Panel Assembly 209

Table of Contents Page

....B.2.04 Printer Assembly (1 of 3) 210

....B.2.05 Printer Assembly (2 of 3) 211

....B.2.06 Printer Assembly (3 of 3) 212

....B.2.07 Base Assembly (1 of 2) 213

....B.2.08 Base Assembly (2 of 2) 214

....B.2.09 Scan Assembly (1 of 2) 215

....B.2.10 Scan Assembly (2 of 2) 216

....B.2.11 Scan Unit (1 of 3) 217

....B.2.12 Scan Unit (2 of 3) 218

....B.2.13 Scan Unit (3 of 3) 219

....B.2.14 Upper Paper Guide Assembly (1 of 2) 220

....B.2.15 Upper Paper Guide Assembly (2 of 2) 221

....B.2.16 Cables (1 of 2) 222

....B.2.17 Cables (2 of 2) 223

....B.2.18 Options 224

....B.2.19 Packaging 225

....B.2.20 Consumables 226

....B.2.21 Documentation 227

Service Guide OF1000

Chapter 0 About This Manual

This document may not be reproduced without written permission of the Okidata® Technical Training Group. Every effort has been made to ensure the accuracy of the information contained in this training course. Okidata is not responsible for errors beyond its control.

© 1994 by Okidata All rights reserved. P/N 59261201 First Edition August, 1993 P/N 59261202 First Edition July, 1994 Written and produced by the Okidata Technical Training Group Please address any comments on this publication to: Okidata Technical Training Group

Page: 2

532 Fellowship Road Mount Laurel, NJ 08054-3499 Facsimile Number: (609) 235-2600, ext. 7034 Okilink Login Name: Technical Training

OKIDATA® is a registered trademark of Oki Electric Industry Company, Ltd.; marques deposee de Oki Electric Industry Company, Ltd.; marca registrada, Oki Electric Industry Company, Ltd.

OKIFAX® is a registered trademark of Oki Electric Industry Company, Ltd. Touch-Tone® is a registered trademark of American Telephone and Telegraph

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Service Guide OF1000

Chapter 1 Product Specifications

1.1.01 General Information

The Okifax 1000 is a Group 3 facsimile unit which utilizes an LED page printer engine to produce a plain paper, permanent copy of received data. The unit can store 85 auto dial locations and has 15 one touch programmable keys. Scanning is accomplished by the direct contact image sensor method. The image sensor consists of 1,728 elements. The Okifax 1000 has a scanning width of up to 8.5 inches.

1.2 GENERAL FACSIMILE SPECIFICATIONS

1.2.01 Style

· Desktop

1.2.02 Compatibility

· CCITT Group 3

1.2.03 Physical Dimensions

· Width

16.1 inches ( Approximately 410 mm)

· Depth

16.4 inches (Approximately 417 mm )

· Height

8.38 inches (Approximately 212.8 mm)

· Weight

26.5 pounds (Approximately 12 kg)

ONLY

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Service Guide OF1000

Chapter 1 Product Specifications

1.2.04 Ambient Temperature and Relative Humidity (RH)

· Operation 50° to 90° F 10° to 30° C 20 to 80% RH

· Storage

-20° to 43° C

-4° to 109° F

Temperature Conversion Formulas

F° to C°:

C°= (F°-32) * .5556 C° to F°: F°= (C°* 1.8) +32

1.2.05 Power Requirement

· 115 vac

1.2.06 Power Consumption Mode

Transmit 40W Receive 120W Local Copy (All black) 118W (580W**) Local Copy 125W Standby 35W

Typical Power

Peak Power when the input voltage is 120V.

1.2.07 LCD Display

· 2-line by 20 digit display

1.2.08 Memory

· Standard Memory 256 Kbytes (up to 14 pages of CCITT No.1 Sample Document)

· Optional Expansion Memory 1 Mbyte (up to 64 pages of CCITT No.1 Sample Document)

1.2.09 Copy Mode Resolution

· Fixed at 200 lines per inch

1.2.10 Warm-up Time

· From power On until printer is ready Maximum of 120 seconds

1.2.11 Receive Options

· Auto Receive

· Manual Receive

· Tel/Fax Receive

· Telephone Answering Device (TAD) Mode

· No Paper Receive

· No Toner Receive

1.2.12 Transmit Document Specifications

· Document Width Minimum 5.8 inches Maximum 8.5 inches

· Document Length Minimum 5 inches (single page), 5.8 inches (multi-page document) Maximum 14 inches, or unlimited length for 1 hour

· Document Weight Range 16 pounds to 24 pounds

· Desired opacity Less than 40 % of the scanner source light should be able to pass through the paper.

1.2.13 Automatic Document Feeder (ADF) Capacity

· 30 sheets (20 pound bond)

1.3 COMMUNICATIONS

1.3.01 Telephone Line Compatibility

· PSTN (public switched telephone network)

· PBX (private branch exchange)

1.3.02 Communication Mode

· Half Duplex

1.3.03 Protocol

· CCITT Recommendation T.30

· Oki Special Protocol In multi-document reception, the local unit can start transmitting the modem training bits immediately after transmitting end of message (EOM) and upon reception of message confirmation (MCF) from the remote unit, instead of repeating all procedures (which takes about six seconds).

· Oki Special High Speed The T.30 handshake is conducted at message transmission speed (instead of 300 bps) during multi-page transmission.

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Service Guide OF1000

Chapter 1 Product Specifications

1.3.04 Line Interface

· Impedance 600 ohms balanced

· Send Power Level 0 dbm to -15 dbm (can be adjusted in 1 dbm steps by modifying TF #21)

1.3.05 Ring Signal Detection Sensitivity

· Voltage Range 25 to 150 r.m.s.

· Frequency Range 15 to 68 Hz (with 44 to 56 volts superimposed)

· Ring Signal Detection Time One Ring Signal or Adjustable between 5 and 30 seconds, in 5 second increments Refer to User Function 24 (optional second tray installed) Refer to User Function 23 (optional second tray NOT installed)

· Ring Signal Voltage Duration Longer than 180 milliseconds (inoperative if duration is 90 milliseconds or less)

1.3.06 Coding Schemes

· Modified Huffman (MH)

· Modified-Modified Read (MMR)

· Modified Huffman (MH)

Only

1.3.07 Error Correction Methods

· CCITT Error Correction Mode (ECM)

· Page Re-transmission (Memory Mode / ECM Off)

1.3.08 High Speed Modem

· CCITT Recommendation V.29 (9600/7200 bps)

· CCITT Recommendation V.27 Ter. (4800/2400 bps)

1.3.09 Low Speed Modem

· CCITT Recommendation V.21 Channel 2 (300 bps)

1.3.10 Transmission Time

· 10 seconds CCITT No. 1 sample document at 9600 bps

1.3.11 Transmit Resolution

· Horizontal 8 PELs per mm (PEL = Picture ELement)

· Vertical STD

3.85 lines per mm or 98 lines per inch FINE

7.7 lines per mm or 196 lines per inch Ex.FINE

15.4 lines per mm or 392 lines per inch

1.3.12 Photo/Half Tone Transmit Resolution

· 32 Levels (using error diffusion)

1.3.13 Ringer Equivalent Number

· 0.68

1.3.14 Transmit Dialing Methods

· Auto Dialing 70 two-digit auto dial codes

· One Touch Dialing 15 one-touch keys)

· Off Hook Dialing

· On Hook Dialing

· Broadcasting Group Dial

1.3.15 Receive Mode

· Auto Receive Dedicated fax machine

· Manual Receive Telephone manual switch to fax mode

· Tel\Fax Auto Switching Telephone will auto switch to fax mode

· TAD Interface

1.3.16 Broadcast Transmit Capabilities

· Maximum: 85 locations in one session

1.3.17 TSI/CSI

· Maximum: 20 characters are displayed. If the function is enabled, the

received TSI is marked at the top of the first reproduced copy.

NOTE: FEDERAL COMMUNICATIONS COMMISSION TELEPHONE CONSUMER PROTECTION ACT

Part 68 Implementation of the Telephone Consumer Protection Act states: " The Telephone Consumer Protection Act of 1991 makes it unlawful for any person to use a computer or other electronic device to send any message via a telephone fax machine unless such message clearly contains in a margin at the top or the bottom of each transmitted page, or on the first page of the transmission, the date and time it is sent and an identification of the business, other entity, or individual sending the message and the telephone number of the sending machine of such business, other entity or individual."

To comply with this law, the End-User must:

1. Enter the DATE and TIME into the Okifax 1000

2. Enter the NAME and TELEPHONE NUMBER to identify the source

of their facsimile transmission.

1.4 PRINTER SPECIFICATIONS

1.4.01 Print Method

· Development Dry electro-photography

· Exposure Stationary LED head

1.4.02 Print Speed

· Continuous Print 4 sheets per minute (letter size)

· Warm-up Time Power-ON (Cold): approximately 120 seconds Idle: approximately 15 seconds

1.4.03 Receive Paper Sizes

· Letter

8.5 inches x 11.0 inches

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Service Guide OF1000

Chapter 1 Product Specifications

· Legal (Option)

8.5 inches x 14.0 inches

1.4.04 Receive Paper Types

· 20 pound Bond Paper

1.4.05 Copy Stacking

· The Okifax 1000 stacks the printed output printed side down. Face-down Stacker Capacity: 100 sheets

1.4.06 Paper Cassette Capacity

· First Cassette 100 sheets

· Second Cassette (Option) 250 sheets

1.4.07 One-Line Minimum Print Time

· Standard Resolution 10 milliseconds per line

· Fine Resolution 5 milliseconds per line

1.4.08 Contrast Selection

· Normal

· Light

· Dark

1.5 USER FUNCTIONS

1.5.0l Transmit Mode

· Auto transmit mode The Okifax 1000 begins sending messages after detecting the remote stations answer.

· Manual transmit mode The operator presses the Start Key after an answer tone has been

heard.

1.5.02 Receive Mode

· Auto Receive Mode

· Manual Receive Mode

· Telephone / Fax Automatic Switch

· TAD Interface

1.5.03 Absent Mode Auto Timer

· This feature enables switching to the auto receive mode at a specified time.

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Service Guide OF1000

Chapter 1 Product Specifications

1.5.04 Group Dial

· One group of up to 85 locations

1.5.05 Telephone Directory and Location ID

· In addition to telephone numbers, an alphanumeric name can be assigned to

each of the numbers. This alphanumeric name is called the Location ID and can contain up to 15 characters.

1.5.06 Voice Request

· A voice request from the transmitter is available only upon completion of the

total message transmission.

1.6 SCANNER SPECIFICATIONS

1.6.01 Scanning Method

· 1728 bit contact image sensor

1.6.02 Effective Reading Width

· Maximum: 8.5 inches

1.6.03 Scanning Resolution

· Horizontal 8 PELs per mm (PEL= Picture ELement) - approximately 200 PELs per inch

· Vertical

3.85 lines per mm or 98 lines per inch (STD)

7.7 lines per mm or 196 lines per inch (FINE)

15.4 lines per mm or 392 lines per inch (Ex.FINE)

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Service Guide OF1000

Chapter 1 Product Specifications

1.6.04 Automatic Document Feeder

· Maximum 30 sheets of 8.5 x 11 inch, 20 pounds bond paper

NOTE: Documents must be placed face down on the ADF document guide.

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Service Guide OF1000

Chapter 1 Product Specifications

1.7 CONSUMABLE ITEMS

1.7.01 Toner Cartridge Kit

· Toner Cartridge

· LED Lens Cleaner Pad

1.7.02 Image Drum Cartridge Kit

· Image drum

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Service Guide OF1000

Chapter 1 Product Specifications

1.8 OPTIONS

1.8.01 Letter / Legal / Universal Paper Tray

· 100 sheet capacity

· Adjustable sizing capability (letter, legal, universal)

1.8.02 Second Tray Unit (ST-250)

· 250 sheet capacity

1.8.03 Memory Expansion Kit

· 1 MByte Memory Card

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Service Guide OF1000

Chapter 1 Product Specifications

1.9 AGENCY APPROVALS

· FCC Class A

· UL 478 Ver. 5

· CSA 22.2 220

1.10 RELIABILITY DATA

1.10.01 Automatic Document Feeder Jam Rate

· Approximately one for every 500 operations

1.10.02 Separation Rubber Life

· Approximately 10,000 document feeds

1.10.03 Lithium Battery Life

· Approximately 5 years

1.10.04 Image Drum Life

· One page print jobs Up to 11,000 pages

· Continuous print Up to 20,000 pages

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Service Guide OF1000

Chapter 1 Product Specifications

1.10.05 Toner Cartridge Life

· First toner cartridge in image drum Up to 1,250 pages

· Subsequent toner cartridges Up to 2,500 pages

1.10.06 Estimated Fuser Life

· Approximately 180,000 pages

1.10.07 Facsimile Mean Time Between Failure (MTBF)

· Approximately 3,000 hours

1.10.08 Printer Duty Cycle

· Approximately 6,000 pages per month

1.10.09 Estimated Printer Life

· Approximately 180,000 pages

1.10.10 Mean Time To Repair (MTTR)

· Approximately 30 minutes

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Service Guide OF1000

Chapter 2 Principles of Operation

2.1 PRINCIPLES OF OPERATION

The Okifax 1000 Principles of Operation section is comprised of three sub-sections.

· Transmitter Theory of Operation

· Receiver Theory of Operation

· LED Printer Theory of Operation

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Service Guide OF1000

Chapter 2 Principles of Operation

2.1.01 Compatibility

The Okifax 1000 facsimile machine operates as a Group 3 (G3) facsimile device.

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Service Guide OF1000

Chapter 2 Principles of Operation

2.1.02 Communications Mode

The Okifax 1000 operates as a half-duplex facsimile transceiver. Transmit and receive operations cannot take place at the same time. However, documents can be prepared for transmission while the Okifax 1000 is engaged in message reception. These documents will be automatically transmitted upon completion of the receiving operation.

Page: 16

Service Guide OF1000

Chapter 2 Principles of Operation

2.1.03 Modem Operation

The high-speed modem conforms to CCITT Standard V.29 for 9600/7200 bps (bits per second) operation and to CCITT Standard V.27 ter. for 4800/2400 bps operation.

The low-speed (300 bps) modem, which is used for handshaking, conforms to CCITT standard V.21 channel 2 or equivalent.

Page: 17

Service Guide OF1000

Chapter 2 Principles of Operation

2.1.04 Automatic Fall-back Mode

The Okifax 1000 will change the message transmitting speed according to the following fall-back plan. The Okifax 1000 will first transmit a page of the message at 9600 bps. The receiving station will continuously monitor the received data. If the receiving station detects six or more consecutive error lines during reception of a single page, or if the total number of errors detected during the reception of a single page exceeds 10% of the data on the transmitted page, it will return an RTN (Retrain Negative) signal to the transmitting station upon termination of the page reception. With an RTN signal received, the transmitting station will downgrade its speed by one level (to 7200 bps in this case) and continue transmission of the next page. Similarly, should the transmitting station again receive an RTN signal from the receiving station, it will downgrade speed another level.

Page: 18

Service Guide OF1000

Chapter 2 Principles of Operation

2.1.05 Telephone Line Connection

The Okifax 1000 is connected to the telephone line via the LINE-JU Board. Two RJ-11 connectors are provided; one for connection to the phone line, and the other for an external telephone. A separate modular jack is provided for connection of the Okifax 1000s handset.

The Okifax 1000 will control the switching between the handset (or the external telephone) and the telephone line to permit use of the handset or telephone for voice communication.

Service Guide OF1000

Chapter 2 Principles of Operation

2.1.06 Error Correction Mode (ECM)

The Okifax 1000 features Error Correction Mode (ECM). When communicating with a remote unit that also has ECM, this feature provides error-free transmission.

What follows is an explanation of how ECM works.

· The transmit machine groups image data into blocks and transmits one block of data at a time to the receive machine. At the end of each block, a PPS (Partial Page Signal) is transmitted.

· The receive machine stores the data block in memory and checks each frame within that block for errors.

- Modified Huffman assigns a binary code to consecutive recurring bits of white or black.

The codes must add up to a total of 1728 bits, which is the Main Scan Rate established by CCITT.

Page: 19

- Modified Read uses a comparison technique. The line being coded is compared to

the previous line and differences are noted. Codes are then assigned to reflect the differences between the two lines.

· If no errors are detected, the receiver sends MCF (Message Confirmation) which requests the transmit machine to transmit the next data block.

· If an error is detected by the receive machine, it transmits the frame number of the defective frame back to the transmit machine in a signal called PPR (Partial Page Request).

· The transmit machine will then re-transmit the frame to the receive machine as a Partial Page.

· The receive machine rechecks the Partial Page, and (if all frames are correct) the receive machine transmits MCF (Message Confirmation).

· The next data block is then transmitted.

Service Guide OF1000

Chapter 2 Principles of Operation

2.1.07 Major Assemblies

The following major assemblies make up the Okifax 1000 facsimile machine.

· Main Control Board MCNT-150

· Printer Interface Board PCNT-150

· Network Control Unit Board NCU-U

· Operation Panel Assembly OPE-150

· Power Supply Board (FXLA) PWU-150

· Sub-Power Supply Board (FXHA) PSUB-150

· Line Board LINE-JU

Page: 20

· Hook Switch Board HOOK SW

· Printer Unit

· Scan Unit

+ 327 hidden pages

Okidata fax 1000 schematic

Specifications and Main Features

Frequently Asked Questions

User Manual