iS R5 rs? X 0."** 0 U,F 1541 MAINTENANCE GUIDE $6.
PI J I PUBLISHED PELTIER BY INDUSTRIES,INC 735 N. Doris Wichita, Kansas 67212 Copyright 1984 by MICHAEL G. PELTIER All rights reserved. Printed in the United States of America. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior permission of the publisher. The information in this manual has been reviewed and is believed to be entirely correct.
WARNING: HIGH VOLTAGE EQUIPMENT THIS EQUIPMENT CONTAINS CERTAIN CIRCUITS AND/OR COMPONENTS OF EXTREMELY HIGH VOLTAGE POTENTIALS. CAPABLE OF CAUSING SERIOUS BODILY INJURY OR DEATH. WHEN PERFORMING ANY OF THE PROCEDURES CONTAINED IN THIS MANUAL, HEED ALL APPLICARLE SAFETY PRECAUTIONS. RESCUE OF SHOCK VICTIMS 1. DO NOT ATTEMPT TO PULL OR GRAB THE VICTIM 2. IF POSSIBLE, TURN OFF THE ELECTRICAL POWER. 3.
TABLE Para. OF CONTENTS Title Page No. FRONT MATTER Title Page Copyright Page Warning Page Table of Contents Section 1-INTRODUCTION 1-1 General 1-2 VIC-1541 1-1 1-3 Warnings, vs.
SECTION 1 INTRODUCTION
Section 1-1. 1-INTRODUCTION General The 1541 Maintenance Guide is produced to give a brief, concise source of pertinent information necessary for maintenance of the VIC-1541 and the 1541 disk drives. Most of the information in this Guide has come from the 1541 Maintenance Manual, which is also published by Peltier Industries. For those persons desiring more thorough coverage of the 1541 series of disk drives, the 1541 Maintenance Manual is available through authorized dealers. 1-2. VIC-1541 vs.
SECTION 2 CALIBRATION
Section 2-1. This 2-CALIBRATION General section contains step-by-step procedures for calibrating VIC-1541. Only one calibration adjustment, to adjust the disk to 300 rpm, is provided in the VIC-1541. calibration procedure at the following intervals: 2-2. 1. Every 6 2. During the process 3. After the the speed of Perform the months. a repair of troubleshooting. action. Equipment Required 1. Small slotted 2. Phillips 3.
ACCESS HOLE FOR VR1 TIMING DISK Figure 2-4, VIC-1541 2-1. Prepared for 60 Hz TIMING MARKS 50 Hz TIMING MARKS Calibration Calibration 1. Connect VIC-20/COMMODORE 64 (Refer to computer User's Guide to video monitor or TV. for proper connection.) 2. Connect serial bus cable between P3 bus connector on VIC-20/COMMODORE 64. 3. Connect AC power cord between J9 on VIC-1541 on VIC-1541 and and serial AC outlet. I warningI • USE EXTREME CARE TO AVOID CONTACT WITH FRAME COMPONENTS.
10. Adjust VR1 appears to (Refer to Figure 2-1) until timing disk stop. # If 60 Hz AC is being used, calibrate with the outer set of timing marks on the timing # If disk. 50 Hz AC the inner is set being used, of calibrate with timing marks on the timing disk. # If further time VR1, go back command 11. After drive switch to to is required to adjust Step 9 and re-enter given. motor has stopped, place VIC-1541 power OFF. 12. Remove serial 13.
2-5. Head Alignment 2-5-1. General This procedure aligns the read/write head to the physical tracks on a floppy disk. A truly accurate alignment requires the use of an alignment reference disk and a test program disk. The procedure which follows allows the user to "get by" without such software. However, the degree of success achieved will depend on the accuracy of the disk which is used.
2-5-2. Equipment Required 1. Alignment standard-use a factory recorded disk which has not been written to since purchase, or a disk which has been formatted on a VIC-1541 which is known to be in proper alignment. 2. Digital Voltmeter 3. Video detector-see Appendix A 2-5-3. Preparation for Mechanical Alignment (Detailed disassembly/assembly instructions can be found in the 1541 Maintenance Manual.) 1. Remove all external cables from VIC-1541 2. Remove upper 3. Remove RFI 4.
3. Connect AC power cord between J9 on VIC-1541 and AC outlet. I WARNING I • USE EXTREME FRAME CARE TO AVOID CONTACT WITH COMPONENTS. HIGH AC VOLTAGE POTENTIALS ARE PRESENT DURING CALIBRATION. THESE VOLTAGE POTENTIALS CAN CAUSE BODILY Place VIC-1541 5. Apply power to VIC-20/COMMODORE 6. If is a VIC-20 7. EVEN the DEATH. to ON. 64. computer being used, command: OPEN 15,8,15, "UI-11:CLOSE enter the 15 Insert disk which will be used as into 8.
14. Apply small amount of Glyptol or fingernail polish to the two screws securing stepping motor housing to keep them from coming 15. loose. Reassemble the VIC-1541. Stepping motor housing screws (2 places) Stepping motor Figure 2-2.
2-6. Mechanical Alignment of Track #1 Stop 2-6-1. General This procedure adjusts the Track #1 Stop. The Track #1 Stop used by the computer in the VIC-1541 for only two purposes: The 1. Formatting a blank 2. Soft procedure verifying error floppy disk ("New" is command). recovery. that follows should that the rest of the VIC-1541 only be used is after carefully properly operating.
TRACK #1 STOP LOCK DOWN SCREW Figure 2-3. Track #1 Page Stop Adjustment.
2. Connect AC line cord between J9 and AC outlet. [WARNING! # DO NOT CONTACT THE FRAME ASSEMBLY OR 3. on WIRING. THE ON THESE PARTS VOLTAGE OR DEATH. POTENTIALS COULD CAUSE Place VIC-1541 power switch computer being used to ON. PRESENT SEVERE to ON and INJURY place power switch # If the VIC-20 is the computer in use, enter the following command: OPEN 15, 8, 15, "U-": CLOSE 15 . 4. Load the Display T&S program into the computer.
SECTION 3 TROUBLESHOOTING
Section 3-1. 3-TROUBLESHOOTING General This section requires only a Multimeter (digital type is recommended) and will isolate a problem down to the sub-assembly level. It is set up so that even an electronics novice can perform the procedures. Troubleshooting consists of step-by-step procedures with accompanying illustrations. Each step either asks a question or refers to the following step. When a question is asked, answer the question with a "Yes" or "No".
8-2. TROUBLESHOOTING-PART STEP 1 1 PROCEDURE ILLUSTRATION Remove AC line cord and serial Remove top cover. bus cables. Remove fuse from fuseholder. Measure resistance of the fuse as follows: 1. Set DMM Multimeter) Ohms x 100. 2. to (Digital to Ohms x Connect one end common of 3. Connect DMM to other Does DMM ohms? lead fuse display or of DMM (A). positive end 10 of lead fuse less YES of (B).
STEP ILLUSTRATION PROCEDURE Determine the frame proper operation of assembly as follows: 1. Disconnect Jl 2. Set measure DMM to from PI. Volts AC. 3. Connect negative lead DMM to pin 1 of Jl (A). of 4. Connect positive lead DMM to pin 4 of Jl (B). of 5. Connect AC between J9 (the receptacle) and line AC cord power an AC outlet. IWARNINGI DO NOT CONTACT DISTRIBUTION 6. ANY AC LINES. Place power switch to ON. Does DMM display between 21.5 Vrms? Step 3.
PROCEDURE STEP 3 (Continue testing Frame Assembly .as follows: 1. Place power switch of 3. DMM Connect positive lead to pin 3 of Jl (B). of 4. Place and DMM 13.5 power switch Frame display between to be working pro perly. Pro ceed to Step 4. 9.5 NO Assembly appears 1 to ON. Vrms? YES I►l Place power switch to OFF. Remove AC line ,cord. Fault lies in Frame Assembly. Re pair or replace Frame Assembly. Place power switch to OFF. Remove AC line cord. Remove shield.
PROCEDURE STEP 6 ILLUSTRATION Place power switch to ON. Measure tests points in table below. Touch positive lead of DMM to indicated test point. Verify that each measurement is within the minimum and maximum limits given. Test Point P8,pinl(A) P7,pinl(B) P7,pin2(C) P5,pin2(D) P6,pin8(E) P6,pin2(F) Min. Max. +4.6V +11.4V +11.4V +11.4V +4.75V +4.6V +5.25V +12.6V +12.6V +12.6V +5.25V +5.25V Are all measurements above within limits specified? YES Place power switch Place to OFF.
ILLUSTRATION PROCEDURE STEP Connect J6 to switch to ON. Does red LED P6. come Place power on momentarily? NO YES Place to Proceed Step Proceed power switch OFF. Step to 9. to 10. Using a short piece of wire, carefully short pin 10 of UF2E (A) to pin 1 of P6 (B) while observing the (Error/Access Does red LED red LED LED). NO YES Place power switch to OFF. Fault lies in Disk Control ler PC Board. Repair or replace.
STEP 11 ILLUSTRATION PROCEDURE Connect positive lead of DMM to pin 3 of J5 (A). Observe DMM while placing power switch to ON. Does DMM indicate 0.0 when the red LED is illuminated? Place power switch to OFF. Fault lies in Drive Unit PC Board. Repair or replace. Using wire, and 2 Place Using short +0.8 V NO YES 12 to Place power switch to OFF. Fault lies in Disk Control ler PC Board Repair or replace. two short lengths of carefully connect pins 1 of J7 to pin 1 of P7. power switch to ON.
SECTION 4 SCHEMATICS AND PARTS LAYOUT
Section 4-SCHEMATICS AND PARTS LAYOUTS 4-1. General This section contains Schematics, Parts Layout Drawings, a Functional Block Diagram and an Interconnect Diagram. These figures are provided for reference purposes. The following index is provided for user convenience: Figure Title Page 4-1^ Interconnect Diagram 4-2 4-2 Sub-Assembly Identification 4-3 4-3 Functional 4-4 Disk Controller, Schematic (Sht. 1 of 2) 4-6 4-5 Disk Controller, Schematic (Sht.
r~ TRACK SELECT I P7 DISK CONTROLLER DRIVE OPTICS UNIT P6 DRIVE MOTOR I P5 READ/WRITE P3 | SERIAL BUS PWR LED P2 CASE ASSY I P8 Figure (PWR LED) 4-1.
CASE ASSY (TOP HALF) SHIELD DISK CONTROLLER PC BOARD J5 FRAME ASSY DRIVE UNIT J8 CASE ASSY Figure 4-2.
Figure 4-3.
it B Figure 4-4. " mi i Disk Controller, Schematic Page 4-6 (Sht.
I 111 ? I i! •! J?J ill si . ill si i lt\ >J1 =f A1! i I" ! ^5 !! II U i " «n« 4* Ut\ M * '■-»" fygr lifiO;; fsTs -S ,8s" ISO si tSS8S8»85 5 t 5 s , §1 n i~ r* 8rTr 6lf A I s . + \, "■I Figure 4-5. Disk Controller, Page Schematic 4-7 (Sht.
00 rt O c h-» O D rt I O CD O ifi Oj en D CD
DSI J8, PWR LED I POWER , (GN) PWR LED I N/C r GND | I CASE ASSY 1 Figure 4-7. Case H | J Assy, Schematic J8 Figure 4-8.
o I O H- rr CD O ft 3 CD CD 04 02 01 03 + I2V + I2V RD RD BR BK OR YL J7, TRACK SELECT 1 1 1 -< 1—C STEPPING MOTOR 1 lJLJLJLJ |
J7 J2 Figure 4-10. Drive Unit, Parts Layout (Top) DS1 DRIVE MOTOR SERVO CIRCUIT Figure 4-11.
% Figure 4-12.
i CM Ul UJ UJ 3 5 o «t UJ UJ O O A O O O z Figure 4-13.
JI,AC INPUT SI, POWER J9,AC LINE 16V 01 OFF AC HI GND 16V 02 AC LO 9V 01 9V 02 Figure 4-14. Frame Assy, Schematic (For use with P.C.Bd. Tl SI, POWER J9,AC LINE OFF Fl I I.OA 1540048-xx) JI,AC INPUT 16V 01 AC HI GND AC LO Figure 4-15. Frame Assy, Schematic Page (For use with P.C.Bd.
Tl Figure 4-16.
Figure 4-17. 1541 Disk Controller, Page 4-16 Schematic (Sht.
Figure 4-18. 1541 Disk Controller, Page 4-17 Schematic (Sht.
Figure 4-19.
APPENDIX A
APPENDIX A Fabrication of Video Detector Materials One One Required: set of meter leads capacitor .oluF,50V One resistor One diode Equipment and IK,10%,1/4 W 1N4148 or equivalent Supplies: Knife Soldering iron Wire cutters Needle nose pliers Heat shrink tubing, 1/2 inch Heat shrink tubing, 3/16 inch Solder, 60/40 resin core Scale (ruler) Ohmmeter String or two wire ties Preparation: 1. Cut meter leads cut as shown below: here Strip 3/16" sides off insulation from both of cut.
3. Prepare resistor as shown below: 3/16' 3/161 4. Tin all leads on resistor, diode and meter leads Assembly: 1. Slide 1 1/2 inch length of 1/8 inch heat shrink tubing onto red meter lead as shown below. Do not shrink the tubing at this time. Heat 3" length of red meter shrinkable tubing (3/16") lead 2. Solder diode, resistor together as shown below. Note Diode and remaining end of meter proper polarity of diode.
one 3. Slide heat shrink tubing over diode and resistor, 4. Solder capacitor and black meter leads as shown below. lead of Tie meter resistor exposed, leads where and then shrink the tubing. shown. Solder here leaving /Capacitor Tie here 31ack meter lead Solder here Tie here 5. Slide a 2 inch length of 1/2 inch heat shrink tubing over then shrink the tubing. capacitor and jCAUTIONl USING POINTS OHMMETER, A AND B VERIFY IS RESISTANCE INFINITY.
APPENDIX B
APPENDIX B Fabrication of Timing Light Materials Required: One neon bulb One One lamp cord with resistor Equipment and appropriate plug 22K/10%/l/4 W (for 47K,10%,l/4 W (for Supplies: Knife Soldering iron Wire cutters Needle nose pliers Heat shrink tubing, 1/8 inch Heat shrink tubing, 3/16 inch Solder, 60/40 resin core Scale (ruler) Ohmmeter Preparation: 1. Prepare lamp cord 2.
3. Prepare neon 4. Tin all lamp as leads on shown below: lamp cord, resistor and neon lamp. Assembly: 1. Slide 1 inch lengths of 1/8 inch heat shrink tubing onto each of the prepared leads of the lamp cord. Do not shrink the tubing at this time. HEAT SHRINKABLE TUBING ~) 7/ (l/8n) \miiu> m 2. Solder components as shown below. Either lead of the line cord may be soldered to the resistor as long as the other lead is soldered to the neon lamp.
3. the neon Slide both pieces of heat shrink tubing toward the base of lamp and then shrink the tubing. 4. Slide a 2 inch length of 3/16 inch heat shrink tubing over neon lamp. Position the end of the heat shrink tubing 3/16 inch up from the base of the neon lamp and then shrink the tubing. I WARNING I BEFORE PLUGGING IN TIMING LIGHT, USE OHMMETER TO VERIFY RESISTANCE BETWEEN POINTS A AND B IS INFINITY.
- ST# 096-1301-3 20 1541 MAINT BK Vec -13- 32-1 31 -k. I '-■■ 'ABLE About the Author Mr. Peltier has nine years professional experience in electronics, technical writing, and circuit and software design. Among his works are: • 1541 Single Drive Floppy Disk Maintenance Manual • 1541 Programmers Reference Card •1541 Heat Dissipating Kit • DAS-1541 (Head Alignment Kit for 1540/1541) .at ■ About the Maintenance Guide By public request the author has compiled this maintenance guide.
