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1800/1810. It is intended for service personnel and other concerned persons to accurately and quickly provide after-sale service for our PT-1800/1810. To perform appropriate maintenance so that the machine is always in best condition for the customer, the service personnel must adequately understand and apply this manual.
1.1 MECHANICAL SPECIFICATIONS 1.1.1 External Appearance Figure 1.1-1 External Appearance [ 1 ] Dimensions (W x D x H) 183 x 205 x 60 mm (7.20" x 8.07" x 2.36") [ 2 ] Weight Machine proper Approx. 730 g In package Approx.
1.1.3 Display [ 1 ] Display type Liquid crystal display (LCD) [ 2 ] Number of columns 12 columns x 2 rows (See Figure 1.1-2.) [ 3 ] Number of indicators 19 (See Figure 1.1-2.) [ 4 ] Character size 5 dots wide by 7 dots high [ 5 ] Dot size 0.524 mm (20.6 mils) wide by 0.58...
If a commercially available high-voltage AC adapter (15.1 V or higher) is connected, the CPU immediately shuts down the power. CAUTION: A commercially available high-voltage AC adapter cannot be used for this machine. It is recommended that a Brother genuine adapter be used. I - 7...
1.3 KEY COMMANDS FOR SPECIAL FUNCTIONS 1.3.1 Initializing Powering on the machine with both the Code and R keys held down will initialize the machine. 1.3.2 Demonstration Print Pressing the D key with the Code key held down will start demonstration print. (This key command takes effect only when no data is entered.) I - 8...
2.1 THEORY OF OPERATION 2.1.1 Print Mechanism n Structure of Thermal Head This machine uses thermal transfer printing. The thermal print head has a heat generator consisting of 128 heating elements (96 out of them are actually used) which are vertically aligned as shown in Figure 2.1-1. Each heating element is 0.195 mm wide by 0.141 mm high.
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[ For non-laminated thermal film tape cassettes ] If the selected heating element(s) generates heat, the thermal film tape develops itself to produce a dot on the tape. The tape is advanced and the next heating cycle is repeated, thus forming a character on the tape. [ For stamp tape cassettes ] If the selected heating element(s) generates heat, the porous-stamp tape will be melted so that a pore (pores) will be formed in the tape.
2.1.2 Platen and Tape Feed Sub Roller Setting & Retracting Mechanism This mechanism consists of the roller release lever, roller release rod, and roller holder ASSY. The roller holder ASSY supports the platen and the sub roller holder so that: •...
2.1.3 Regular Tape & Ribbon Feed Mechanism This mechanism consists of a drive motor, gear train, and roller holder ASSY. n Regular Tape Feeding When you load a tape cassette and close the cassette cover, the tape feed roller inside the cassette and the tape feed sub roller in the roller holder ASSY sandwich the tape (the laminate tape and adhesive base tape when using laminated tape cassettes) inbetween, as described in Subsection 2.1.2.
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n Adhesive Base Tape Feeding (only for laminated tape cassettes) A laminated tape cassette contains both a transparent laminate tape roll and a separate adhesive base tape roll. When a transparent laminate tape and an adhesive base tape pass through the contact point (between the tape feed roller and tape feed sub roller), they are then bonded together into a single, printed tape.
2.1.4 Tape Cutter Mechanism The cutter unit consists of a stationary blade and a movable blade. Pressing the cutter lever actuates the movable blade so that the cutter cuts the printed tape routing through the movable and stationary blades, just like a scissors. Attached to the cutter lever, the cutter sensor arm turns up so that its tip comes into contact with the switch of the cutter sensor circuit on the main PCB, stopping printing and tape feeding.
2.1.5 Roller Holder ASSY & Cassette Cover Interlocking Mechanism Closing the cassette cover pushes down the roller release lever and brings the top of the lever into the hooked section provided on the inside of the cassette cover. As described in Subsection 2.1.2 "Platen and Tape Feed Sub Roller Setting & Retracting Mechanism", the roller release lever shifts the roller release rod so that the roller holder ASSY is pressed towards the thermal head side.
2.2 DISASSEMBLY & REASSEMBLY 2.2.1 Disassembly Procedure [ 1 ] Removing the Battery Lid and Batteries (1) Turn the machine upside down. (2) Press section "A" of the battery lid to remove, then take out batteries. Figure 2.2-1 Removing Batteries II - 8...
[ 2 ] Removing the Tape Cassette (1) Place the machine rightside up and open the cassette cover fully. (2) Pull the tape cassette up and out of the machine. Figure 2.2-2 Removing the Tape Cassette II - 9...
[ 3 ] Removing the Bottom Cover (1) Close the cassette cover while pressing down sections "B." (2) Turn the machine upside down. (3) Remove seven screws from the bottom cover. (4) Apply your fingers to the bottom cover and pull it up. When you separate the bottom cover from the boy cover, the cassette cover may also be removed.
[ 4 ] Removing the Chassis ASSY During the following job, handle the connectors and harnesses gently so as not to damage them. (1) Remove the screw that secures the anti-static lead wire to the chassis. (2) Disconnect the thermal head cable from the main PCB. •...
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n Disassembling the Chassis ASSY Removing the roller holder ASSY and thermal head ASSY (1) Remove the retaining ring from the roller holder ASSY. (2) Lift up the roller release lever as shown below and pull up the roller holder ASSY together with the roll release lever and rod, making sure that the roller holder spring does not go flying off.
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Removing the cutter ASSY WARNING: Take care not to touch the blade of the cutter ASSY. (1) Remove the cutter spring. (2) Remove two screws from the cutter ASSY, then take off the ASSY. CAUTION: To remove the right-hand screw, push down the left end of the movable blade to turn it counterclockwise, taking care not to push it down excessively or let the left end of the cutter spring touch the cutting edge of stationary blade.
[ 5 ] Removing the Main PCB and Rubber Key Pad When you handle the PCB, it is recommended that an anti-static mat be used. If you have built up a static charge, touching the PCB without any anti-static control may damage the LSI and other electronic devices.
[ 6 ] Removing the Cassette Sensor PCB Remove the cassette sensor PCB from the body cover by pulling the three pawls outwards. Figure 2.2-10 Removing the Cassette Sensor PCB [ 7 ] Removing the Blind Cover Remove the blind cover from the bottom cover by pulling the three pawls outwards. Figure 2.2-11 Removing the Blind Cover II - 15...
[ 8 ] Removing the Power Supply PCB (1) Remove the positive (+) and negative (-) terminals of the battery power cords from the bottom cover. • When handling those terminals, do not grip the cords but the terminal plates. (2) Remove the screw from the power supply PCB.
2.2.2 Reassembly Procedure [ 1 ] Installing the Battery Terminals (1) Place the bottom cover upside down and fit one battery terminal into the bottom cover as shown below (left). (2) Fit the other battery terminal into the bottom cover as shown below (right). Figure 2.2-14 Installing the Battery Terminals [ 2 ] Installing the Power Supply PCB (1) Fit the positive (+) and negative (-) terminals of the battery power cords into the...
[ 3 ] Installing the Blind Cover Fit two holes "A" of the blind cover over the pins provided on the bottom cover and push down the blind cover until pawls "B" catch the hooks on the bottom cover. Figure 2.2-16 Installing the Blind Cover [ 4 ] Installing the Cassette Sensor PCB (1) Check that the switch actuators are not deformed.
[ 5 ] Installing the Rubber Key Pad Place the rubber key pad so that it is fitted over the bosses provided on the body cover. Figure 2.2-19 Installing the Rubber Key Pad [ 6 ] Installing the Main PCB Check that there is no foreign material or dust on the key contacts on the main PCB, then install the PCB.
[ 7 ] Installing the Chassis ASSY (1) Set the cutter lever to the body cover. (2) If the chassis ASSY has been disassembled, assemble the components by referring to the next page. (3) Pull down the roller release lever to the vertical position and install the chassis ASSY onto the body cover.
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n Assembling the Components of the Chassis ASSY Installing the cutter ASSY WARNING: Take care not to touch the blade of the cutter ASSY. (1) Secure the cutter ASSY to the chassis with two screws. Tightening torque: 490 ±196 mN•m (5 ±2 kgf•cm) (2) Hook the cutter spring as shown below.
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Installing the roller holder ASSY and thermal head ASSY (1) Install the thermal head ASSY with a screw. Tightening torque: 490 ±196 mN•m (5 ±2 kgf•cm) (2) First fit the roller holder spring and the assembly of the roller release lever and rod onto the roller holder ASSY as shown below.
[ 8 ] Installing the Bottom Cover (1) As shown below, route the power supply harness through the grooves provided on the bottom cover and then connect it to the main PCB. (2) Align the front edge of the bottom cover with that of the body cover, then push down the bottom cover until it snaps into place.
[ 9 ] Installing the Cassette Cover (1) Place the machine rightside up. (2) Lift up the roller release lever. (3) Hold the cassette cover at an angle shown below and slide down its hinges until they become fitted into the bottoms of the grooves provided in the bottom cover. (4) Close the cassette cover.
[ 10 ] Installing the Tape Cassette (1) Fully open the cassette cover. The roller release lever pops up to retract the roller holder ASSY from the thermal print head. (2) Load a tape cassette. (3) Close the cassette cover. (The roller holder ASSY will be pressed against the thermal head.) Figure 2.2-26 Installing the Tape Cassette and Cutter Unit...
[ 12 ] Demonstration Print and Final Check (1) Press the key (On/Off key). (Make sure that the AC adapter is not connected.) (2) While holding down the Code key, press the key (Del key) to cancel data previously entered. (3) While holding down the Code key, press the D key to start the demonstration print.
3.1 OUTLINE OF CONTROL ELECTRONICS Figure 3.1-1 shows a block diagram of the control electronics of the PT-1800/1810. The control electronics consists of three printed circuit boards (main PCB, sensor PCB, and power supply PCB), a DC motor, and a thermal print head assembly.
3.2 MAIN PCB 3.2.1 Block Diagram Figure 3.2-1 shows a block diagram of the main PCB. The main PCB consists of the following: CPU (including a ROM and RAM) CG ROM LCD driver Key contacts matrix and solder points Power ON/OFF circuit and power saving circuit Motor driver circuit Thermal head drive circuit Voltage detector circuit and temperature sensor circuit...
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Figure 3.2-1 Block Diagram of Main PCB III - 3...
3.2.2 The CPU (#4: MN101C28D) is an 8-bit microprocessor produced by the CMOS silicon gate process, which integrates a 64-kilobyte ROM and a 2048-byte RAM. 3.2.3 Key Contacts Matrix [ 1 ] Key contacts matrix On the main PCB is a key contacts matrix that is a set of 50 carbon-printed key contact patterns (except for the On/Off key).
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Figure 3.2-3 Timing Scheme and Waveforms of Key Scanning by the CPU III - 5...
[ 2 ] Solder points Figure 3.2-4 shows a circuit diagram relating to the key pad and solder points. Solder points 1 through 3 customize the machines for the destination (keyboard specification) as listed below. Solder points LA0121xxx LA0122001 LA0120001 LA0101001 No point soldered England...
3.2.4 Power ON/OFF Circuit and Power Saving Circuit [ 1 ] Power ON/OFF circuit Figure 3.2-5 shows a circuit diagram of the power On/Off key. The CPU processes the On/Off key state in a sequence quite different from other keys although it is on the key pad.
Powering-off sequence (See Figure 3.2-6.) 1) Interrupted by IRQ0, the CPU starts the chattering elimination program module. 2) If pin 31 is Low for 10 ms, the CPU recognizes the On/Off key as being pressed and then transfers the control to the sleep program module. If pin 31 is High, the CPU interprets the input as a noise and keeps the main program module.
3.2.5 Motor Driver Circuit Figure 3.2-8 shows a driver circuit of the DC motor which feeds tapes and ink ribbon. Through P10, the CPU issues a start/stop control signal to the motor driver circuit. Figure 3.2-9 shows the control signal and drive current waveforms. The DC motor integrates an electronic governor circuit which handles the variation of the drive source voltage (VBT), in order to keep the rotation speed constant.
Thermal Head Drive Circuit Figure 3.2-10 shows the thermal head drive circuit. The print head used in the PT-1800/1810 integrates a heat generator (consisting of 128 heating elements vertically aligned at 180 dpi) and a built-in driver IC. Synchronizing with the clock on P02, the CPU outputs print data on P00 in the serial form.
3.2.7 Voltage Detector Circuit and Temperature Sensor Circuit Figures 3.2-12 and 3.2-13 (See next page) show the voltage detector circuit and the ambient sensor circuit, each of which is composed of a resistor network. [ 1 ] Voltage detector circuit This circuit, which is composed of divider resistors R8 and R9, steps down the power source VBT fed from batteries or the AC adapter output and feeds the output to the A/D input port PA1 on the CPU.
Figure 3.2-12 Voltage Detector Circuit [ 2 ] Ambient temperature sensor circuit This circuit is composed of a resistor R13 and a thermistor TH1. It converts the resistance of TH1 (whose internal resistance varies depending upon the ambient temperature) to the voltage variation, and then feeds its output to the A/D input port PA0 on the CPU.
3.2.8 Cassette Sensor Circuit Figure 3.2-14 shows the cassette sensor circuit. This circuit reads the states of the five sensor switches which come on or go off depending upon the ID holes provided in the tape cassette currently mounted. By receiving the states of those sensor switches, the CPU identifies the tape cassette type (tape width and ink ribbon type).
3.2.9 Cutter Sensor Circuit Figure 3.2-15 shows the cutter sensor circuit. Pushing down the cutter lever pivots the attached cutter sensor arm whose tip comes into contact with the switch of the cutter sensor circuit provided on the main PCB. Upon receipt of the signal through port P21, the CPU stops printing and tape feeding.
3.2.10 Oscillation Circuit Figure 3.2-16 shows the oscillation circuit. It generates 20 MHz source which acts as the CPU basic clock. The CPU divides this into half (10 MHz) to synchronize its internal operations. Figure 3.2-16 Oscillation Circuit 3.2.11 Reset Circuit Figure 3.2-17 shows the reset circuit.
3.2.12 +5BV Power Source Figure 3.2-18 shows a circuit diagram of the +5BV power source. A 3-terminal regulator S-81350 stabilizes the battery output or the AC line adapter output, producing the +5BV power source within the variation of ±0.15V. Figure 3.2-18 +5BV Power Source III - 16...
3.3 POWER SUPPLY PCB Figure 3.3-1 shows a circuit diagram of the power supply PCB. Capacitor C1 is for the logic circuit; capacitor C2 is for the thermal print head and DC motor drive sources. Connecting the AC adapter plug with the AC jack J1 cuts off the power fed from the batteries and feeds power from the AC adapter.
4.1 TROUBLESHOOTING This section gives the service personnel some of the troubleshooting procedures to be followed if an error or malfunction occurs with this machine. It is impossible to anticipate all of the possible troubles which may occur in future and determine the troubleshooting procedures, so this chapter covers some sample troubles.
[ 6 ] Tape cassette type not identified IV - 13...
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APPENDICES Circuit Diagrams A: Main PCB B: Power Supply PCB...
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Appendix A. Main PCB V C C L C D R E S R E S L C D A 0 C 1 5 L C D R W R / W V C C L C D E D B 7 D B 7 N J U 6 4 5 0 1 0 K...
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Appendix B. Power Supply PCB Battery Terminal B L K R E D C C V Ferrite Bead J A C K R 0 R 8 C 3 R 0 A 3 V B T A K 0 3 V B T D 4 7 0 0 ( 1 6 V ) 1 0 0 0...