Keithley Model 750 User manual

INSTRUCTION MANUAL
Model 750 Printer

WARRANTY
We warrant each of our products to be free from defects in material
and workmanship. Our obligation under this warranty is to repair
or replace any instrument or part thereof which, within a year after
shipment, proves defective upon examination. We will pay local
domestic surface freight costs.
To exercise this warranty, write or ca~ll your local Keithley repre-
sentative, or contact Keithley headquarters in Cleveland, Ohio.
You will be given prompt assistance and shipping instructions.
REPAIRS AND
CALIBRATION
Keithley Instruments maintains a complete repair and calibration
service as well as a standards laboratory in Cleveland, Ohio.
A Keithley service facility at our Munich, Germany office is
available for our customers throughout Europe. Service in the
United Kingdom can be handled at our office in Reading. Addition-
ally, Keithley representatives in most countries maintain service
and calibration facilities.
To insure prompt repair or recalibration service, please contact
your local field representative or Keithley headquarters directly
before returning the instrument. Estimates for repairs, normal
recalibrations and calibrations traceable to the National Bureau of
Standards are available upon request.
KEITHLEY
The measurement engineers.
Keithley Instruments, Inc., 28775 Aurora Road, Cleveland, Ohio 44139. [phone]
European Headquarters: Heiglhofstrasse 5, D-8000 Munchen 70 West Germany, [phone]
United Kingdom: 1 Boulton Road, Reading, Berkshire, [phone]
France: 44 Rue Anatole France, F-91121 Palaiseau (01) 014-22-06

INSTRUCTION MAYUAL
Model 750 Printer
OCOPYRIGHT 1976, KEITHLEY INSTRUMENTS, INC.
SECOND PRINTING, AUG. 1978, CLEVELAND, OHIO, U.S.A.
DOCUMENT NO. 27965, REVISION CODE AA.

INSTRUCTION MANUAL
Model 750 Printer
CONTENTS
Section Page
CONTENTS ...................................... ii
ILLUSTRATIONS. ................................... iii
SPECIFICATIONS ................................... iv
1. GENERAL INFORMATION. .............................. l-l
l-l. INTRODUCTION ............................... l-l
1-2. WARRANTY INFORMATION ........................... l-l
l-3.
CHANGE NOTICE. .............................. l-l
2. INITIAL PREPARATION. .............................. 2-l
2-l. GENERAL..................................2- I
2-2. INSPECTION ................................ 2-l
2-3. PREPARATION FOR USE. ........................... 2-l
2-4. HOW TO INSTALL ACCESSORY PLUG-IN CARDS .................. 2-l
2-5.
HOW TO INSTALL PRINT PAPER (FAN-FOLD OR ROLL). ..............
2-3
2-6. HOW TO INSTALL RIBBON. .......................... 2-6
2-J. HOW TO RACK MOUNT THE MODEL 750. ..................... Z-J
3.
OPERATING INSTRUCTIONS .............................
3-l
3-l.
GENERAL..................................
3-l
3-2. HOW TO USE FRONT PANEL CONTROLS. .....................
3-1
3-3.
HOW TO OPERATE THE PRINTER ........................
3-l
3-4. INTERFACING THROUGH I/O "A". ....................... 3-2
3-5.
INTERFACING THROUGH I/O "6". ....................... 3-5
4. ACCESSORIES. ..................................
4-l
4-l.
PRINTER INPUT INTERFACES ......................... 4-l
4-2. MODEL 7503 PRINTER CLOCK ......................... 4-l
4-3. MODEL 7504 SEQUENCE COUNTER. .......................
4-1
5.
THEORY OF OPERATION. .............................. 5-l
5-l.
INTRODUCTION ............................... 5-l
5-2. OVERALL FUNCTIONAL DESCRIPTION ...................... 5-l
5-3.
PRINT SEQUENCE DESCRIPTION ........................ 5-1
6. MAINTENANCE. .................................. 6-l
2:::
GENERAL .................................. 6-1
MECHANISM - SIMPLE MAINTENANCE ...................... 6-1
6-3. ELECTRONIC CIRCUITRY ........................... 6-4
7.
REPLACEABLE PARTS. ............................... 7-1
J-1.
GENERAL.................................. 7-1
7-2.
ORDERING INFORMATION ........................... 7-l
7-3.
SCHEMATICS ................................ J-l
APPENDIX A. MODEL
7503 PRINTER CLOCK. ....................... A-l
APPENDIX B. MODEL 7504 SEQUENCE COUNTER ...................... B-l
APPENDIX C. MODEL 7502 PRINTER INPUT INTERFACE. .................. C-l
APPENDIX D. CHASSIS REPLACEABLE PARTS ....................... D-l
APPENDIX E. RACK MOUNTING INSTRUCTIONS. ...................... E-l
APPENDIX F. COMPONENT LAYOUTS ........................... F-l
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INSTRUCTION MANUAL
Model 750 Printer
ILLUSTRATIONS
igure
NO. Title Page
1 Front and Rear Views of Model 750 ..................... l-2
2 Installation of Accessory Plug-in Cards .................. 2-2
2 How to Open the Front Panel to Access the Mechanism ............ 2-4
How to Install Fan-Fold or Roll Paper ................... 2-4
2 View of Paper Feed Mechanism. ....................... 2-5
How to Replace Ribbon ........................... 2-6
; Timing For External Print Command ..................... 3-4
Timing For Red Print. ........................... 3-4
9 Timing For PIC x 2. ............................ 3-4
10 Top View of Chassis Showing Roll and Fanfold Paper Installed. ....... 3-8
II Model 7503 Clock. ............................. 4-2
12 Model 7504 Sequence Counter ........................ 4-2
13 Simplified Block Diagram. ......................... 5-2
14 Top View of Printer With Cover Removed. .................. 6-3
15 Assembly of Chassis ............................
16 6-5
Mother Board Assembly ........................... 6-5
17 Assembly of Connector Board ........................ 6-6
18 Controls and Modifications to Model 7503. ................. A-2
19 Diagram of Time Set For Model 7503. .................... A-3
20 Diagram of Model
750/7503 Operation .................... A-4
21 Component Layout of PC-374. ........................ A-5
22 Block Diagram of Model 7503 ... .................................... : : A-6
23 Pin Identification for Connector J502 A-8
24 Model 7504 Controls and Connectors. .................... B-2
25 Diagram of Model
750/7504 Operation .................... B-3
26
Block Diagram of the Model 7504 ...................... B-4
27
Component Layout of Model 7504 (~~-385)
..................
B-6
28
Model 7502 General Purpose Printer Input Interface. ............ C-2
:: Chassis Parts Identification. ....................... D-2
Handle Assembly For Model 750 ....................... E-2
31 Model 1011 Rack Mounting Kit. ....................... E-4
;: Model 1012 Rack Mounting Kit. ....................... E-6
Model 1015 Rack Mounting Kit. ....................... E-9
34
Model 1014 Rack Mounting Kit. ....................... E-l
;z Model 1016 Rack Mounting Kit. ....................... E-l Component Layout, PC-380. ......................... F-l
Component Layout, PC-378. ......................... F-3
Location of Test Points Described in Section 5. .............. F-4
AA
iii

INSTRUCTION MANUAL
Model 750 Printer
SPECIFICATIONS
low-to-high transition,
CONTROL OUTPUT: Printer-in-Cycle (PIG); End-of-Print Data
Hold: Manual Print: Print Twice.
iv
AA

INSTRUCTION MANUAL
Model 750 Printer
SECTION I. GENERAL INFORMATION
SECTION 1
l-l. INTRODUCTION. The Keithley Model 750 Printer is a medium speed, ink impression,
line printer designed for use with Keithley digital measuring instruments and other
digital instrumentation.
a. Printing Capabilities. The tlodel 750 records up to 18 columns of data per line.
Columns 3 through I8 print numeric data, while columns 1 and 2 of the printer are re-
served for measurement units and contain no numeric characters. Columns 3, 4, 5 can
print certain measurement units (see Table 3-5 on page 3-7). Columns 6 through IO and 12
through 15 contain a floating decimal point which can be printed to the right of any one
of the numeric data columns, without deleting numerical data in that umn. Either
adding machine roll paper (Z-1/4 inch width) or fan-fold paper can bf ;ed.
b. Accessory printer Input Interfaces are available for use with t thley digital mea-
suring instruments. The factory-wired interfaces are plug-to-plug cb,,, atible so 'that
installation is very simple to perform. All data is properly encoded and formatted for
printout of data, decimal point, range, and units of measurement (where available at the
digital output). See ACCESSORIES Section 4 for more detailed information regarding
accessory interfaces for Keithley instruments as well as for general purpose applications.
l-2. WARRANTY INFORMATION. The warranty is given in the Keithley general catalog. If
there is a need for service, contact your Keithley representative or authorized repair
facility as given in our catalog.
l-3. CHANGE NOTICE. Improvements or changes to the instruvent not incorporated into the
manual will be explained on separate instruction manual addenda sheets.
CAUTION
Since input Lo can float to 350 volts peak with respect to chassis ground, care
should be exercised when making connections to either I/O "A" or "BP. Turn off
power to all instruments c0nnectp.d before plug-in cards are installed or removed,
or cable connections are made. If I/O "B" is not used, make certain the cover
plate is installed to prevent the possibility of electrical shock.
AA l-l

SECTION 1 INSTRUCTION MANUAL
Model 750 Printer
PAPER CUTTING BAR
JZOI
J202
POWER INDICATOR
DS301
POWER S3OIA
PAPER FEED S3OlB
RUN S301C
MANUAL PRINT S301
'PRINT INTERVAL
s103/~106
LINE VOLTS SIOI
FUSE FIOI
POWER P105
C
FIGURE I. Front and Rear Views of Model 750.
l-2 AA

INSTRUCTION MANUAL
Model 750 Printer
SECTION 2. INITIAL PREPARATION
SECTION 2
2-l. GENERAL. This section provides information needed for incoming inspection and
preparation for use.
2-2. INSPECTION. The Model 750 was carefully inspected both mechanically and electri-
cally before shipment. Upon receiving the instrument, check for any obvious damage
which may have occurred during transit.
verify the electrical specifications, Report any damages to the shipping agent. To follow the procedures in Section 5.
2-3. PREPARATION FOR USE.
a. How to Set the Line Switch. The rear panel LINE Switch should be set to the
appropriate nominal setting as shown in Table 2-l. For example,
be used is 120 volts, if the line voltage to set the LINE Switch to "117". If the line voltage to be used is
within 105 and llOV, then either range (100 V or 117 V) may be selected.
TABLE 2-l.
Voltage Ranges Useable With Model 750
Range of Voltage Appropriate Setting Fuse Rating
go - IIOV I oov 3/4A
105 - l25V 117v 3/4A
200 - 240V 22ov 3/8A
b. Line Fuse Requirements.
shown in Table 2-l. The Model 750 uses a 3AB or 3AG Slow-Blow fuse with rating
The line fuse is located on the rear panel as shown in Figure I.
C. Line Power Connections. An accessory line cord is furnished with the Model 750.
The 3-wire, 8 foot (244 cm) line cord mates with the rear panel receptacle p]Ol. An
extra line cord can be ordered from Keithley by specifying Keithley Part No. CO-7.
2-4. HOW TO INSTALL ACCESSORY PLUG-IN CARDS.
a. Model 7501 Printer Input Interface Cards. These cards have card-edge connectors
which mate with I/O "A" receptacle on the Model 750 chassis. Before installinq a card,
remove the cover plate at I/O "A" by pulling the two plastic buttons. To install the
card align the card-edge to mate with grooved tracks on the chassis as shown in Figure 2.
The "component side" should face the users right hand when viewing the rear panel as
illustrated. The two plastic buttons should be pulled out (unlocked). After the card
is installed, lock the card in place by pushing in the buttons on the rear panel. The
Model 7501 can not be inserted in I/O "B".
b. Models 7502, 7503, and 7504 Plug-In Cards. These cards have card-edge connectors
which mate with I/O "6" receptacle on the Model 750 chassis. Before installing a card,
remove the cover plate at I/O "B" by pulling the two plastic buttons. To install the
card align the card-edge to mate with grooved tracks on the chassis as shown in Figure 2.
The "component side" should face the 'users right hand when viewing the rear panel as
AA
2-1

SECTION 2 INSTRUCTION MANUAL
Model 750 Printer
NO COMPONENTS I t
MOUNTED THIS SIDE
CAUTION
TURN OFF POWER TO THE MODEL
750 AND MEASURING INSTRUMENT
BEFORE INSTALLING OR REMOVING
PLUG-IN CARD. IF I/O "B" IS
NOT USED, MAKE CERTAIN THE
COVER PLATE IS INSTALLED TO
PREVENT THE POSSIBILITY OF
ELECTRICAL SHOCK.
.\
FIGURE 2. Installation of Accessory Plug-in Cards.
2-2 AA