Keithley 706 Service manual

Model

706

Scanner

Instruction Manual

Contains Operating and Servicing Information

Publication Date: April 1991
Document Number: 706-901-01 Rev. E

WARRANTY

Keithley Instruments, Inc. warrants this product to be free from defects in material and workmanship for a period of 1 year from date of
shipment.

Keithley Instruments, Inc. warrants the following items for 90 days from the date of shipment: probes, cables, rechargeable batteries,
diskettes, and documentation.

During the warranty period, we will, at our option, either repair or replace any product that proves to be defective.

To exercise this warranty, write or call your local Keithley representative, or contact Keithley headquarters in Cleveland, Ohio. You will
be given prompt assistance and return instructions. Send the product, transportation prepaid, to the indicated service facility. Repairs
will be made and the product returned, transportation prepaid. Repaired or replaced products are warranted for the balance of the origi­nal warranty period, or at least 90 (lays.

LIMITATION OF WARRANTY

This warranty does not apply to defects resulting from product modification without Keithley’s express written consent, or misuse of
any product or part. This warranty also does not apply to fuses, software, non-rechargeable batteries, damage from battery leakage, or
problems arising from normal wear or failure to follow instructions.

‘ITHIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTlE S, EXPRESSED OR IMPLIED, INCLUDING ANY IMPLIED
WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. THE REMEDIES PROVIDED HEREIN ARE
BUYER’S SOLE AND EXCLUSIVE REMEDIES.

NEITHER KEITHLEY INSTRUMENTS, INC. NOR ANY OF ITS EMPLOYEES SHALL BE LIABLE FOR ANY DIRECT, INDI­RECT, SPECIAL, INCIDENTAL QR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OF ITS INSTRUMENTS AND
SOFTWARE EVEN IF KEITHLEY INSTRUMENTS, INC., HAS BEEN ADVISED IN ADVANCE OF THE POSSIBILITY OF
SUCH DAMAGES. SUCH EXCLUDED DAMAGES SHALL INCLUDE, BUT ARE NOT LIMITED TO: COSTS OF REMOVAL

AND INSTALLATION, LOSSES SUSTAINED AS THE RESULT OF INJURY TO ANY PERSON, OR DAMAGE TO PROPERTY.

Keithley Instruments, Inc. l 28775 Aurora Road l Cleveland, OH 44139 l 216-248-0400 l Fax: [phone] l http://www.keithley.com

CHINA:
FRANCE
GERMANY:
GREAT BRITAIN:
ITALY: Keitbley Instruments SIk l Viale S. Gimigoano 38 l 20146 Milano l 39-2-48303008. Fax: [phone]
JAPAN:
NETHERLANDS:
SWITZERLAND:
TAIWAN

Keitbley Instruments Cl&m. Yuan Chen Xio Building, Room 705 l No. 12Yomin Road, Dewei, Madian. Beijing, China loo029 l 8610-2022886 l Fax: [phone]
Keitbley Instruments SAkL l BP 60.3 al& des Garays -91122 Palaiseau C&&x l 31-6-0115155. Fax: [phone]
Keitbley Instruments GnibH l Laodsberger Stralk 65 l 82110 Germering l 49-89-849307-o l Fax: [phone]
Keitbley Instruments, Lt& l The Minster l 58 Portman Road l Reading, Berkshire RG30 IEA 9 44-01734-575666 *Fax: [phone]

Keitbley Instruments F& East KK l Aibido Bldg. * 7-20-2 Nishishinjuko . Shiojuku-ko, Tokyo 160 l 81-3-5389-1964 * Fax: [phone]
Keitbley Instruments Bv l Avelingen West 49 l 4202 MS Gorinchem l 31-(0)183-635333 l Fax: [phone]
Keithley Instruments Sk* Kriesbachstrasse 4 l 8600 Diibendorf* 41-1-8219444 l Fax: 41-l-8203081
Keitbley Instruments Taiwan l 1, Ming-Yu First SUeet * Hsinchu, Taiwan, R.0.C * 886-35-778462 l Fax: [phone]

Model 706 Scanner

Instruction Manual

01983, Keithley Instruments, inc.

Test Instrumentation Group

All rights reserved.

Cleveland, Ohio, U.S.A.

Fifth Printing, April 1991

Document Number: 706-901-01 Rev. E

SPECIFICATIONS

GENERAL

DISPLAY: Seven 0.5” LED digits with decimal point, function and

IEEE status annunciators.

INTERNAL CLOCK: Displays hours/minutes/seconds or date/

month; less than 1 minute/month error (typical).

BATTERY BACKUP: Rechargeable 3.6V nickel-cadmium. I month

retention of data with unit turned off.

OPERATING ENVIRONMENT: O” to 50°C, 0% to 80% relative

humidity up to 35OC.
STORAGE ENVIRONMENT: -25OC to 65OC.
CONNECTORS; Four BNC (lTL compatible): External Trigger,

Alarm Out/Serial-In, Channel Ready, Serial Out.
CAPACITY: Ten plug-in cards per mainframe.
EXPANSION CAPACITY: Daisy chain allows up to 4 SLAVE units

with I MASTER unit.
SWITCHING RATE: 100 channels/second (IOmsl, programmable

to 1 channel/l6 minutes (999.999s).
RELAY DRIVE: 4A minimum.
POWER: 90-125V or 195250V (internally selected), 50Hz to 400H2,

75V.A maximum.
DIMENSIONS, WEIGHT: 178mm high x 438mm wide x 448mm

deep (7” x 17 l/4” x 17 3/8”). Net weight 8.6kg (19 Ibs).

ACCESSORIES AVAILABLE:

Model 7008-3: IEEE-488 Cable, 0.9m (3 ft.)

Model 70086: IEEE-488 Cable, 1.8m (6 ft.)

Model 7010: IEEE-488 Adapter for Model 85 Computer.

Model 7024-I: Triaxial Cable, 0.3m (I ft.)

Model 7024-3: Triaxial Cable, 0.9m (3 ft.)

Model 7024IO:Triaxial Cable, 3.0m (IO ft.1

Model 7051-2: BNC to BNC Cable, 0.6m (2 ft.)

Model 7051-5: BNC to BNC Cable, 1.5m (5 ft.)

Model 7052: 4 x 5 Matrix Card

Model 7053: High Current Scanner Card

Model 7054: High Voltage Scanner Card

Model 7056: General Purpose Scanner Card

Model 7057A: Thermocouple Scanner Card

Model 7058: Low Current Scanner Card

Model 7059: Low Voltage Scanner Card

Model 7061: Universal Interface Card

Model 7068: Fixed Rack Mounting Kit for 706

Model 7069: Slide Rack Mounting Kit for 706

IEEE-488 BUS IMPLEMENTATION:

Multiline Commands: DCL, LLO, SDC, GET, GTL, UNT, UNL,

SPE, SPD.
Uniline Commands: IFC, REN, EOI, SRQ, ATN.
Interface Functions: SHI, AHI, T6, TM, L4, LEO, SRI, RLI, PPO,

DCI, DTI, CO, El.
Programmable Parameters: Display Mode, Output Format, EOI,

SRQ, Fir&Last, Open, Close, Display Channel, Alternate Output,

Pole Mode, Date Format, Save/Recall, Reset, I/O Port, Time,

Date, Settle Time, Interval Time, Alarm Time, Program Mode,

Trigger Mode, Terminator, Self Test.
Digital I/O Port: A separate edge connector consisting of eight

input and eight output lines as well as common and + R/DC. Out-

puts will drive one lTL load. Inputs represent one lTL load.

Mating connector supplied.

FRONT PANEL PROGRAMS

0

- Digital I/O

I* - Date Format

2* - Settle Time

3* - IEEE Address

4* - Save Setup

5* - Recall Setup
6* - Poles

- Alarm Time

7
8 - Self Test

Stand Alone

go* ­91, - Master
92* - Slave

93 - Inspect

- Clear

94

- Reset

99

*Battery backed up.

Read or change state on digital I/O port.
Changes date display between MM.DD

and DD.MM.
Time to output CHANNEL READY pulse
after closing relay.
Set bus address; not programmable from

bus.
Stores present relay setup in buffers l-75.
Recalls relay setup in buffers l-75.

1, 2, or Qpole configuration for scanning

(I-pole requires 7056). O-pole for matrix
card.
Set time for Alarm output pulse; repeats
daily.
Check RAM, ROM, LEDs.
Single 706 configuration.

Daisy Chain configuration.

Daisy Chain configuration.

Display closed relays only.
Clear buffer location.

Reset battery backup parameters to fac­tory values.

Speclfi+lons subject to change without notice.

Safety Precautions

The following safety precautions should be observed before using
this product and any associated instrumentation. Although some in­struments and accessories would normally be used with non-haz­ardous voltages, there are situations where hazardous conditions
may be present.

This product is intended for use by qualified personnel who recog-

nize shock hazards and are familiar with the safety precautions re-

quired to avoid possible injury. Read the operating information

carefully before using the product.

Exercise extreme caution when a shock hazard is present. Lethal
voltage may be present on cable connector jacks or test fixtures.

The American National Standards Institute (ANSI) states that a

shock hazard exists when voltage levels greater than 30V RMS,

42.4V peak, or 60VDC are present.

pect that hazardous voltage is present in any unknown circuit
before measuring.

Before operating an instrument, make sure the line cord is connect­ed to a properly grounded power receptacle. Inspect the connecting
cables, test leads, and jumpers for possible wear, cracks, or breaks
before each use.

For maximum safety, do not touch the product, test cables, or any

other instruments while power is applied to the circuit under test.

ALWAYS remove power from the entire test system and discharge

any capacitors before: connecting or disconnecting cables or jump-

ers, installing or removing switching cards, or making internal

changes, such as installing or removing jumpers.

Do not touch any object that could provide a current path to the

common side of the circuit under test or power line (earth) ground.

Always make measurements with dry hands while standing on a

dry, insulated surface capable of withstanding the voltage being

measured.

A good safety practice is to ex-

Do not exceed the maximum signal levels of the instruments and
accessories, as defined in the specifications and operating informa­tion, and as shown on the instrument or test fixture panels, or
switching card.

Do not connect switching cards directly to unlimited power circuits.
They are intended to be used with impedance limited sources.
NEVER connect switching cards directly to AC main. When con­necting sources to switching cards, install protective devices to lim­it fault current and voltage to the card.

When fuses are used in a product, replace with same type and rating

for continued protection against fire hazard.

Chassis connections must only be used as shield connections for
measuring circuits, NOT as safety earth ground connections.

If you are using a test fixture, keep the lid closed while power is ap­plied to the device under test. Safe operation requires the use of a
lid interlock.

Ifa @
#18 AWG or larger wire.

The
or more may be present on the terminals.
ual for detailed operating information.

Instrumentation and accessories should not be connected to hu-

mans.

Maintenance should be performed by qualified service personnel.
Before performing any maintenance; disconnect the line cord and
all test cables.

screw is present, connect it to safety earth ground using

symbol on an instrument or accessory indicates that 1OOOV

t

Refer to the product man-

TABLE OF CONTENTS

Paragraph

SECTION l-GENERAL INFORMATION

1.1

1.2

1.3

1.4
E

1:7

1.8

1.9

;-:
2:2.1

2.2.2

2.3
z.2

2:5.1

2.5.2

2.5.3

2.5.4

2.6
E

2:9

2.9.1

2.9.2

2.9.3

2.9.4

2.9.5

2.9.6

2.9.7

2.9.8

2.9.9

2.9.10

2.9.11

2.9.12

2.9.13

2.9.14

2.9.15

Introduction
Model 706 Features

Warranty information.

Manual Addenda

Safety Symbols and Terms

Unpacking and Inspection

Specifications.............................................;.-

Optional Accessories

Repackingforshipment
SECTION 2-OPERATION

Introduction

PreparationforUse

PowerUp .....................................................................................

Environmental Condition
Operatinglnstructions

Front Panel Clock Operation

Detailed Front Panel Controls Description

DetailedRearPanelDescription

Front Panel Programs.

...................................................................................

.............................................................................

...........................................................................

...............................................................................

.......................................................................

........................................................................

............................................................................

.........................................................................

...................................................................................

..............................................................................

CorrectLineVoltage
Plug-In Card (Scanner) Installation

FrontPanelControls
Rear Panel Description.
Basic Front Panel Operation
ScanningExamples

Program 0 Digital I/O
Program 1 Data Format
Program 2 Relay Settle Time
Program 3 Set IEEE Primary Address
Program 4 Save Relay Set Up
Program 5 Recall Relay Set Up
Program 6 Pole Configuration, Matrix Mode
Program 7 Set Alarm Time
Program 8 Diagnostic Self Test.
Program 90 Stand Alone

Program 91 Master.

Program92Slave

Program 93 Inspect
Program 94 Clear
Program 99 Reset

...........................................................................

............................................................... 2-l

.........................................................................

...........................................................................

...........................................................................

........................................................................

....................................................................

...........................................................................

..................................................................... 2-13

.......................................................... 2-14

..................................................................

..........................................................................

.........................................................................

.......................................................................

...................................................................

...........................................................

..................................................................

................................................................. 2-21

....................................................................

................................................................ 2-25

......................................................................

..........................................................................

............................................................................

.........................................................................

............................................................................

............................................................................

Title

...................................

....................................................... 2-22

Page

l-l
l-l
l-l
l-l
l-l
l-l
l-l
l-2
1-3

2-1
2-l
2-l

2-2
2-3
2-3
2-3
2-3
2-7
2-8

2-17
2-18
2-19
2-19
2-20

2-20
2-21

2-24
2-25

2-25
2-26
2-26
2-27
2-28

3.1

3.1.1

3.1.2

3.1.3

3.1.4

3.2

3.2.1

3.2.2

3.2.3

3.3

SECTION 3-IEEE BUS OPERATION
Introduction

Software Consideration

HP-85BASlCStatements
Interface Function Codes.
Mode 706 Interface Commands

IEEE488 Bus Lines

Bus Management Lines
Handshake Lines
Data Lines

System Set Up Procedure

...................................................................................

........................................................................ 3-l

......................................................................

......................................................................

.................................................................

..............................................................................

........................................................................

.............................................................................

................................................................................... 3-4

........................................................................

3-l
3-l

3-2
3-3
3-3

ifi

3-4

i

;*i 1
31412

3.4.3

3.5

3.5.1

3.5.2

3.5.3

3.5.4

3.5.5

3.5.6

3.5.7

3.58

3.6

3.7

3.8

3.9

3.9.1

3.9.2

3.9.3

3.10

Bus Commands

Uniline Commands
Universal Commands
Addressed Commands

Device-Dependent Commands

DisplayMode
Program(Scan)Mode..
Prefix..
EOI(EndorIdentify)
BusResponseMode(SRQ)

TriggerModes

Programmable Terminator (Y)

Inputs....................................................-.

StatusByteFomat
Status Word (U)
Front Panel Programs
FrontPanelErrorMessages

IDDCError

No Remote Error.

IDDCOError
ScanningProgram

................................................................................

............................................................................

..........................................................................

.........................................................................

....................................................................

...............................................................................

......................................................................

....................................................................................

..........................................................................

.................................................................... 3-16

............................................................................... 318

..................................................................

.............................................................................

...............................................................................

..........................................................................

......................................................................

..................................................................................

............................................................................

................................................................................

.............................................................................

.................................

;1;

331:
3-14
3-15
3-16

3-18

3-19
3-27
3-28
3-29
3-29
3-29

3-29
3-29
3-29

4.1

4.2

4.3
f.2

5.1

5.2

5.3

5.4

5.5

5.5.1

5.5.2

5.5.3

5.5.4

5.5.5

5.5.6

5.6

5.7

6.1

6.2

6.3

6.4

6.5

SECTION 4-THEORY OF OPERATION
Introduction
PowerSupply
Microcomputer
DisplayCircuit
IEEE-488lnterfaceCircuitry

SECTION 5-MAINTENANCE

Introduction ...................................................................................

FuseReplacement
LineVoltageSelection

Disassembly ...................................................................................

Troubleshooting

RecommendedTestEquipment

DigitalSelfTest
PowerSupplyChecks
DigitalCircuitryChecks

Display Boards Check
InterconnectBoardChecks

BatteryCharge
Special Handling of Static Sensistive Devices

SECTION 6-REPLACEABLE PARTS
Introduction
Pa&List
Orderinglnformation..
Factory Service.
Component Location Drawings and Schematic Diagrams

...................................................................................

..................................................................................

.................................................................................

..................................................................................

.......................................................................

..............................................................................

...........................................................................

................................................................................

.................................................................

...............................................................................

.........................................................................

........................................................................

............. T

.....................................................................

.................................................................................

...................................................................................

......................................................................................

..........................................................................

................................................................................

...........................................................

........................................................

..............................................

4-1
4-l
4-l
4-3
4-3

5-l
5-l
5-1
5-3
5-6
5-6
5-6
5-7
5-7
5-7

z
5-8

6-l
6-l
6-l
6-l
6-1

LIST OF FIGURES

.‘.

Title

..

lI. .~.._‘.... _.

................................... 6-17/6-18

................................... 6-21/6-22

Figure

1-I

Model706Scanner
Scanner Card Installation

;::

FrontPanelControl ..................................................................

Model706RearPanel

;:“4

Daisy Chain Configuration
Model7052MatrixScheme

2-5

Matrix Display Clarification

;:y

BusStructure
3-2
3-3

$2

HandshakeSequence ................................................................

ContactAssi
TypicalBus
Digital I/O Port Pin Assignment

UandGModeSequence

3-6

StatusByte Format

g;:

Status Word Format

IEEE Display Error Messages

3-9

Model706BlockDiagram

4-1

Model706MemoryMap

2::

Topand BottomCoverRemoval ........................................................

PowerSup IyExplodedView

2::

Model706

Display Board, Component Location Drawing, Dwg. No. 706-l 10

6-l

Digital I/O Board, Component Location Drawmg, Dwg. No. 706-170

6-2

Mother Board, Component Location Drawing, Dwg. No. 706-I 10

6-3

Interconnect Board, Component Location Drawing, Dwg. No. 706-I 60

6-4

Display Board, Schematic Diagram, Dwg. No. 705-l 16

6-5

Digital I/O Board, Schematic Diagram, Dwg. No. 706-176

6-6

Mother Board, Schematic Diagram, Dwg. No. 706-I 06

6-7

Interconnect Board, Schematic Diagram, Dwg. No. 706-l 66

6-8

8 onnector ...............................................................

L1-

opView

..................................................................

.............................................................

...............................................................

............................................................

...........................................................

............................................................

......................................................................

nments ................................................................

.........................................................

.............................................................

..................................................................

.................................................................

.........

..........................................................

.............................................................

..............................................................

..........................................................

.:. .:.

.. I ..

Page

1-o
;:$I

22;7
2-23
2-24

;:;
3-5

3-5
3-24
3-27
3-28
3-28
3-29

z

5-2

..............................

..............................

............................ 6-10

........................... 6-I 1/6-l 2

....................... 6-l 5/6-i 6

................................. 6-19/6-20

............................... 6-25/6-26

5-4

5-5

6-9

LIST OF TABLES

Table

LineVoltageSetting

2-1
2-2 Slot Number/Channel Number Assignment
2-3 Power Up Default Conditions (Front Panel Operation)
2-4 Front Panel Controls
2-5 Rear Panel Description

2-6 StepScanExample ..................................................................

2-7 SingleScanExample

2-8 ContinuousScanExample
2-9 Required Equipment for Daisy Chain Example
2-10 Daisy Chain Example
2-11 Temperature Scan Example
2-12 Low Current Scan Example
2-13 SettingtheTime
2-14 SettingtheDate
2-l 5 Maximum Relay Drive Current from Mainframe
2-l 6 CANCEL Function Example
2-17 Summary of Front Panel Programs
2-l 8 Scanner Card Pole Configuration
2-19 Matrix Unit Number Display Assignment

.................................................................

.................................................................

...............................................................

................................................................

............................................................

................................................................

...........................................................

...........................................................

....................................................................

....................................................................

...........................................................

......................................................

.................. .,

..................................................

Title

...............................................

.......................................

.............................................

............................................

....................................

Page

2-1

2-l

g:;
2-7

;:g

2-10
2-l 0
2-l 1

12-12

2-13
2-l 3
2-14
2-15
2-16
2-19
2-22
2-24

Iii

LIST OF TABLES (CONT.)

2-20 Matrix Card Number Display Assignment
2-21 Program 99 Reset Condition
3-l HP-85 IEEE-488 BASIC Statements
3-2 Model 706 Interface Function Codes
3-3 IEEECommand Groups
34 IEEE Bus Connector Contact Designations
3-5 Power Up, DCL and SDC Default Conditions
3-6 Device-Dependent Commands Not Available to the Front Panel
3-7 Model 706 Device-Dependent Commands
3-8 Hierarchy of Command Execution
3-9 SRQ Commands and Conditions
3-10 Digital I/O Port Contact Pin Assignments
5-l Fuse Replacement 3AG Size.
5-2 Fuse Replacement 5mm Size
5-3 Line Voltage Selection.

54 RecommendedTestEquipment .....................................................................

5-5 PowerSupplyChecks

5-6 DigitalCircuitn/Checks ............................................................................

5-7 DisplayBoardChecks .............................................................................

5-8 InterconnectBoardChecks

5-9 Model 706 Static Sensitive Devices

6-l Model 706 Recommended Spare Parts List.
6-2 Index of Model 706 Schematics and Component Layouts.
6-3 Display Board Parts List

6-4 Mother Board Parts List

6-5 Digital I/O Board Parts List

6-6 Interconnect Board Parts List

6-7 Model 706 Mechanical Parts List

.......................................................................

............................................................................

...................................................................

.......................................................................

.......................................................................

............................................................................

.............................................................................

.........................................................................

........................................................................... 6-2

...........................................................................

.........................................................................

.......................................................................

....................................................................

............................................................

..................................................................

.................................................................

............................................................

..........................................................

..........................................

...........................................................

..................................................................

............................................................

..................................................................

...........................................................

...............................................

2-24
2-29

3-2
3-3
3-3
3-5
3-6

3-9
3-10
3-12
3-16

3-24

5-l

5-l
5-l
5-6

5-6

5-7

5-7
5-8

5-8

6-l

6-l

6-3

6-5

6-6

6-7

Iv

1-O

Figure l-l. Model 706 Scanner

SECTION 1

GENERAL INFORMATION

1.1 INTRODUCTION
The Model 706 is an IEEE488 bus compatible scanner that

can accommodate ten plug-in scanner cards. With ten scan­ner cards installed up to 100 2-pole channels can be on the
same IEEE address. Using four additional Model 706s in a
daisy chain configuration up to 500 2-pole channels can be
on the same IEEE address. The Model 706 scanner adheres to

standard IEEE488 interface bus protocol. This enables the

Model 706 to be incorporated into any measurement that
uses programmed control through the IEEE-488 bus.

The front panel controls are clearly marked and easy to use.
These controls serve several functions such as opening a
selected channel, closing the channel, scanning between a
selectable first and last channel, selecting scan rate and
mode. There are 15 internal programs that are accessible
from the front panel. The programs can select primary ad­dress, settling time, store a relay set up, recall the stored relay
set up, control the digital I/O port, switch from International
to American date format, start or stop a scan sequence,
select 1, 2 or 4-pole measurement modes and program the

Model 706 as a master, slave or stand alone instrument in a
daisy chain configuration. The Model 706 may also be
operated in a matrix configuration.

The time and date are kept internally with a battery backed up
clock allowing time dependent procedures to be performed.

1.2 MODEL 706 FEATURES

The Model 766 scanner includes the following features:
.lJp to 100 2-pole channels.

aIEEE-488 bus operation.
*Selectable scan rate of IOmsec to 999.999sec.
aSelectable scan modes that enable the user to scan the first

channel to the last channel once, continuously or manually.

*Fifteen internal programs that are accessible from the front

panel.

aModel 706 mainframe can accomodate 10 scanner plug-in

cards.

*Several different plug-in scanner cards are available as op-

tions. They include: a general purpose relay card, a ther­mocouple card, low voltage card, low current card, high

current card, high voltage card, matrix card and universal in­terface card.

*Time and date are kept with a battery backed up clock.
*Digital I/O port with eight lines as inputs and eight lines as

outputs.

*External trigger input that accepts a greater than wet

negative going TTL compatible pulse for triggering the
Model 706 into a scan sequence.

@Channel ready output that outputs a greater than IOFec

negative going lTL compatible pulse upon the completion

of the programmed channel settling time.

*Alarm output that outputs a negative going lTL level

greater than 10,usec pulse when the programmed time is
reached.

1.3 WARRANTY INFORMATION
Warranty information is provided on the inside front cover of

this manual. If there is a need to exercise the warranty, con­tact your Keithley representative in your area to determine the
proper action to be taken. Keithley maintains complete repair
and calibration facilities in the United States, West Germany,
Great Britain, France, the Netherlands, Switzerland and
Austria. Information may be directed to the applications
engineer at any of the above locations. Check the inside front
cover of this manual for addresses.

1.4 MANUAL ADDENDA
Improvements or changes to this manual will be explained on

an addendum included with this manual.

1.5 SAFETY SYMBOLS AND TERMS

Safety symbols used in this manual are as follows:
The symbol ’

should refer to the operating instructions.
The symbol AM

voltage may be present on the terminals.
The, WARNING used in this manual explains dangers that

could result in personal injury or death.
The CAUTION used in this manual explains hazards that

could damage the instrument.

1.6 UNPACKING AND INSPECTION

The Model 706 is inspected both electrically and mechanically

before shipment. Upon receiving the Model 706, unpack all

items from the shipping container and check for any obvious
damage that may have occurred during transit. Report any
damage to the shipping agent. Retain and use the original

packaging materials if reshipment is necessary. The following

items are shipped with all Model 706 orders:

*Model 706 Scanner
*Model 706 Instruction Manual

*Optional accessories per request. (Cards are shipped

separately. 1

1.7 SPECIFICATIONS
For Model 706 detailed specifications, refer to the specifica-

tions that precede this section.

on the instrument denotes that the user

Q

on the instrument denotes that high

1-l

+

1.8 OPTIONAL ACCESSORIES

Switching Cards - Keithley offers over 20 different models of
switching cards. In addition to general purpose scanning and
matrix applications, cards are designed for special applications
with signal handling capabilities that include:

l

Low voltage switching to 20nV.

l

Low current switching to 1 OfA.

l

High frequency switching to 500MHz.

o Thermocouple switching with a precision temperature refer-

ence.

l

High voltage switching to 1 OOOV.

Further details on switching cards can be obtained by contact-

ing a Keithley representative or sales office.

Model 7008-3 IEEE-488 Cable-The Model 7008-3 is a 1 me­ter (3 feet) IEEE-488 cable. The cable has 24 stranded wire
conductors and is terminated on each end with IEEE-488 stan­dard connectors.

Model 7008-6 IEEE-488 Cable-The Model 7008-6 is a 2 me­ter (6 feet) IEEE-488 cable. The cable has 24 stranded wire
conductors and is terminated on each end with IEEE-488 stan­dard connectors.

Model 7010 Cable Adapter-The Model 7010 is an IEEE-488
cable adapter. The adapter extends the IEEE-488 connector by
one connector width.

Model 7051-2 1 The Model 7051-2 is a (2 feet) BNC to BNC
cable. It is especially useful for daisy chain operation.

Model 7051-5 - The Model 7051-5 is a (5 feet) BNC to BNC

cable. It is especially useful daisy chain configuration.

Model 7068 Fixed Rack Mount-The Model 7068 is a fixed or
stationary rack mounting kit that mounts the Model 706 in a
standard 19 inch rack. The dimensions are 13-3/4 inches deep

x 7 inches high (350mm x 178mm).

Model 7069 Slide Rack Mount with Handles - The Model
7069 is a sliding rack mount kit. It enables one Model 706 to be

rack mounted with the added feature of sliding the instrument
for easy access. The dimensions are 3-3/4 inches deep x 7
inches high (95mm x 178mm).

1.9 REPACKING FOR SHIPMENT

The Model 706 should be packed in its original carton. Before
packing, wrap the instrument in plastic. After it is placed in the
box, surround the instrument with Styrofoam packaging mate­rial. Remove all cards and ship separate.

If the Model 706 is to be returned to Keithley Instruments for

calibration or repair, include the following:

l

Write ATTENTION REPAIR DEPARTMENT on the address
label.

= Include the warranty status of the instrument.

l

Photocopy and complete the service form at the back of this
manual and return it with the instrument.

1-2

+

SECTION 2

OPERATION

2.1 INTRODUCTION
Operation of the Model 706 is divided into two sections: front

panel operation and IEEE-488 bus operation. IEEE bus opera-

tion is located in Section 3. This section contains the follow-

ing information:
*Preparation for use

@Power Up
iEnvironmental Conditions
*Front and Rear Panels Description
@Examples of Scanning
aFront Panel Programs

2.2 PREPARATION FOR USE

2.2.1 Correct Line Voltage
Connect the Model 706 to the proper power receptacle (refer

to Table 2-l). For fuse replacement or line voltage setting
refer to Section 5 Maintenance.

WARNING
Ground the instrument through a properly
earth grounded receptacle before opera­tion. Failure to ground the instrument can
result in severe injury or death in the event
of a short circuit or malfunction.

1. To install a scanner card, slide the card into the appropriate
vertical slot. The slots are numbered 1 through 10. Refer to
Table 2-2 for slot number/ channel numbers assignment.
Facing the rear panel of the Model 706, the scanner card
component side should face the left side of the slot. Make
certain the card edges are aligned with the top and bottom
grooves in the slot.

2. Once the card is aligned with the grooves, insert the card
to its full depth into the Model 706. Make certain the card
is properly seated into the connector on the interconnect
board. When the card is fully inserted, the locking tabs on

the card should be placed in the locked position as shown

in Figure 2-1.

3. To remove a scanner card, first turn the Model 706 off and
disconnect the line cord. Unfasten the locking tabs by pull­ing both tabs outward. Grasp the end of the card and pull it

out of the mainframe.

NOTE
Handle the scanner cards by the edges to avoid
contaminating them with dirt, body oil, etc.

WARNING
Do not insert scanner cards that have metal
clamps into the Model 706. Otherwise a

shock hazard will be present. Only use
scanner cards that have plastic clamps.

2.2.2 Plug-In Card (Scanner) Installation
Before operating the Model 706, the appropriate scanner

cards must be installed into the mainframe. Each scanner

card (up to 10 cards per the Model 706 mainframejis installed
in-the appropriate vertical slot in the rear panel of the Model

706. Refer to Figure 2-l for an overall picture of scanner card

installation.

WARNING
To prevent a possible shock hazard, turn
the instrument off and disconnect the line
cord before installing/removing any scan­ner card.

Table 2-l. Line Voltage Setting

Input Jumper I Line Fuse

Voltage

9OV-125v Installed

195v-250v

Setting 3AG

Not
Installed

Table 2-2. Slot Number Channel Number Assignment

Slot

Number

1
2
3
4
5

7”
ii

10

“Does not include other units in a daisy cha;

configuration see paragraph 2.5.4 example 4.

FlOl .

5mm

1.25A, 1.25A, installed
250V 250V

0.6A, 0.6A, not
250V 250V installed

Varistor

Channels

Included

l-10

11-20
2130
31-40
41-50
51-60
61-70
71-60
81-90

91-100

VR2

2-l

LOCKING TABS

MODEL706 /

REAR PANEL

SCANNER CARD

INSTALLATION

Figure 2-l. Scanner Card Installation

2.3 POWER UP
When the Model 706 is turned on the instrument goes

through a power up sequence that is outlined as follows:

NDLES

After the software revision level is displayed, the Model 706
displays the primary address of the instrument for approx­imately 0.5 seconds. The primary address of the Model 706 is
factory set at 18.

Immediately after turing on the Model 706 via the power
switch, the display indicates the following for a number of
seconds:

1

1

1. This is a display test. The operator can note inoperative
display segments by comparing the Model 706’s display
with the figure above.

2. In addition, the pushbutton and the TALK, LISTEN and

REMOTE indicators turn on. All indicators turn on

simultaneously if operating correctly.

After the display test is complete, the Model 706 displays the
software revision level for approximately 0.5 seconds. The

following is an example of software revision level Al.

RI I

‘2-2

r---r-q

During the display test the Model 706 performs a digital self

test of the RAM circuitry and a cyclic redundancy check

(CRC) of the ROM circuitry. If a problem is found by these

tests the Model 706 displays a diagnostic number. This

number and its meaning is described in detail in Section 5.

After all the displays and test of the power up sequence, the
Model 706 comes to the default conditions that are listed in

Table 2-3.

NOTE
If upon power up the Model 706 displays the
slave or no loop message (refer to paragraphs

2.9.11 and 2.9.12) activate Program 90 to return
the Model 706 to normal operating conditions.
To activate Program 90, press PRGM, 9, 0.

Table 2-3. Power Up Default Conditions (Front Panel Operation)

Function or
Program

CHANNEL
TIME Time is not affected by power up.
DATE
RESET
INTERVAL
SINGLE
CONTINUOUS Continuous scan mode is set to inactive.
START/STOP
Program 0
Program 1
Program 2 Settle time is not affected by power up.
Program 3
Program 4 Save relay set up is cleared from display but still in memory. Channel 1 is displayed.
Program 5
Program 6 Number of poles is not affected by power up.
Program 7 Alarm time is set to 00.00.00.
Program 8 Self test is not activated.
Program 90
Program 91
Program 92 Program 92 is not affected by power up.

Program 93
Program 94

Program 99
FIRST
LAST
CLOSE
OPEN

*If channel 1 was previously programmed as the first channel, last channel, both or neither, it is displayed as such.

The FIRST and LAST functions are not affected by power up.

Default Conditions
Channel mode is selected, channel 1 is displayed and all channels are open.*

Date is not affected by power up.
Reset is not affected by power up.
Interval time is not affected by power up.
Single scan mode is set to inactive.

Start/Stop function is set to stop.
Digital I/O outputs are set to 000, the inputs are not affected by power up.
Date format is not affected by power up.

Primary address is not affected by power up. ..
Recall relay set up is cleared from display but still in memory. Channel 1 is displayed.

Program 90 is not affected by power up.

Program 91 is not affected by power up.

Program

Program 94 is not affected by power up.

Program 99 is not affected by power up.
The first function is not affected by power up.
The last function is not affected by power up.
All channels are open.
All channels are open.

93 is set to inactive.

To identify the previous state of the functions that are not af­fected by power up simply activate the desired function.
When the function is activated the previous state for that
function is displayed. Refer to paragraph 2.5.1 for informa­tion concerning the actuation of the desired function.

2.4 ENVIRONMENTAL CONDITIONS
All operation of the Model 706 should take place at an am-

bient temperature within the range of O°C to 50°C, up to
35OC at 80% noncondensing relative humidity. Environmen-

tal conditions for storage are -25OC to +65OC.

NOTE
If the Model 706 internal operating temperature
is higher than 75OC the thermal breaker on the
power supply will open up. This action will shut
down the Model 706. Refer to Section 5
paragraph 5.5.3.

2.5 OPERATING INSTRUCTIONS

2.5.1 Front Panel Controls
Table 2-4 lists all the front panel controls and buttons. Their

operation and function are briefly described in the table. For
complete details concerning the front panel controls refer to
paragraph 2.7. Refer to Figure 2-2 for a view of the front
panel controls.

2.5.2 Rear Panel Description
Table 2-5 lists all the rear panel connectors and terminals.

Their function and operation are briefly described in the table.

For complete details concerning the rear panel refer to
paragraph 2.8. Refer to Figure 2-3 for a view of the Model 706
rear panel.

2-3

Table 2-4. Front Panel Controls

Control
POWER ON/OFF

CHANNEL

CLOSE
OPEN
FIRST

LAST
RESET
INTERVAL

CONTINUOUS

SINGLE

START/STOP

PRGM

DATA
ENTER

CANCEL

TIME

DATE

TALK”

LISTEN*
REMOTE*

*Refer to Section 3 IEEE-488 bus operation.

Description

Turns the unit on or off.
Selects channel mode, turns on the channel LED and displays channel information (e.g.
open or closed, first or last). Increments channel number by one each time it is acti­vated when in the channel mode.
When activated the CLOSE button closes the presently displayed channel. Close is
indicated by a c on the far right digit of the display.
When activated the OPEN button opens the presently displayed channel. Open is indi­cated by an o on the far right digit of the display.
When activated the FIRST button specifies the presently displayed channel as the first
channel of a multi channel configuration. First is indicated by an F in the middle of the
display.
When activated the LAST button specifies the presently displayed channel as the last
channel of a multi channel configuration. Last is indicated by an L on the display.
When activated the RESET button opens all channels and reverts the display to the
specified first channel.
The INTERVAL button selects the programmed interval time for display and turns on the
interval LED. The interval time is the programmed time each channel is closed in a
scanning sequence.

The CONTINUOUS button selects the continuous scan mode and turns on the

continuous LED. The continuous scan mode allows the user to scan through the
programmed channels in a continuous cycle upon the actuation of the START/STOP

button.
The SINGLE button selects the single scan mode and turns on the SINGLE LED.
The single scan mode allows the user to scan through the programmed channels

one time upon the actuation of the START/STOP button.
The START/STOP button when activated initiates the selected scan mode and turns

on the START/STOP LED. Pressing the button during a scan stops the scan sequence

and turns off the START/STOP LED. When not in the continuous or single scan modes the

START/STOP button activates the STEP scan mode. Refer to paragraph 2.5.4.
The PRGM (Program) button when activated shows a display that prompts the user to

select one of the 15 front panel programs. Refer to paragraph 2.9 for complete
details and examples of the front panel’programs.
The O-9 buttons allow entry of numerical data onto the display.
The ENTER button loads the displayed data for the interval time, channel number,
time, date and program modes into the Model 706.

During the entry of data (C segment cursor is flashing) the CANCEL button cancels
the present display and reverts the instrument to the previous display.
When activated the TIME button selects for display the 24 hour time clock and

turns on TIME LED.
When activated the DATE button selects the date mode for display and turns on

the DATE LED.
When lit the TALK LED indicates that the Model 706 is in the talk mode.

When lit the LISTEN LED indicates that the Model 706 is in the listen mode.
When lit the REMOTE LED indicates that the Model 706 is in the remote mode.

I-

.2-G:

I

I . I

Table 2-5. Rear Panel Deswiption

Connections Description
Card Slots

SER. OUT

Each slot accepts one scanner card. There are a total of 10 slots.

The serial output connector is a female BNC connector that provides

connection to another Model 706 for a daisy chain configuration.

ALARM/SERIAL IN

The alarm function of this female BNC connector outputs a pulse when the

programmed alarm time is reached. The serial in function is used in a
daisy chain configuration where serial in is connected to the serial out of
another Model 706.

CHANNEL READY

This female BNC connector outputs a pulse at the completion of the pro­grammed channel settling time.

EXT. TRIGGER

This is a female BNC connector that initiates the selected scan mode upon
receiving the proper signal pulse.

DIGITAL I/O

The digital I/O port consists of 16 digital input/output lines along with four
lines that are +5V and IEEE common.

IEEE-488 INTERFACE

This standard connector provides connection to the IEEE-488 bus.

CONNECTOR

FUSE

The line power fuse provides protection for the AC power line input and is
rated as shown in Table 2-l.

AC Power Receptacle

The line power receptacle mates with three wire line cord and applies the
line power to the instrument.

2.5.3 Basic Front Panel Operation
This section provides the information necessary for basic

front panel operation of the Model 706. There are a number
of steps to follow in order to get the Model 706 ready for
scanning operation. These steps are as follows:

1. Install the desired scanner card(s). Refer to paragraph 2.2.2
for information concerning the installation of the scanner
cards into the Model 706.

2. Select appropriate line voltage. Refer to Section 5
Maintenance for information concerning the selection of

appropriate line voltage and proper fuse rating.

3. Turn on the Model 706. The instrument then goes through

the power up sequence that is described in paragraph 2.3
and displays one of the following:

I[ (Normal Condition)

(Matrix Mode Refer to

I o 1 Paragraph 2 9 71

. .

NOTE
If upon power up the Model 706 displays the
slave or no loop message (refer to paragraphs

2.9.11 and 2.9.12) activate Program 90 to return
the Model 706 to normal operating conditions.
To activate Program 90, press PRGM, 9, 0.

NOTE
Channel 1 is set as the programmed first chan­nel. If another channel was previously program­med as the first or last channel, then the F or L

will not be displayed upon power up.

4. Program the desired channel. (Channel mode is selected
upon power up).

A. Select the first channel.

1. Press the desired channel number from the DATA
group buttons O-9.

2. Press the FIRST button to program the presently
displayed channel as the first channel.

NOTE
Selecting a channel that does not exist in the
present set up causes the Model 706 to display
the following message.

no

Ch

B: Select the last channel.

1. Press the desired number from the DATA group but­ton O-9.

2. Press the LAST button to program the presently

-

dispkyed channel as the last channel.

5. Program the number of poles (0, 1, 2 or 4).
A. Press PRGM.
B. Press 6.
C. Select number of poles (0, 1, 2 or 4).
D. Press ENTER.

NOTE
The 0 pole mode is the matrix mode. Refer to
paragraph 2.9.7 for complete details concerning
programming of the different poles.

6. Program the interval time.
A. Press the INTERVAL button to select interval mode for

display.

B. Enter the interval time on the display by pressing from

the DATA group the desired time, within the limits of

000.010 to 999.999 seconds.

C. Press the ENTER button.

7. Program the desired scan mode. Press the SINGLE or
CONTINUOUS button to select one of these two scanning
modes. To select the step scan mode press the CHANNEL
button.

8. Press the START/STOP button to start the scanning se-

quence. For the step mode press the START/STOP but­ton each time a single channel is to be scanned.

Upon the actuation of the START/STOP button in step 9,
channel 1 is closed and the START/STOP LED is turned on.
Channel 1 remains closed for two seconds (programmed in­terval rate) and then opens. The START/STOP LED turns off
and the Model 706 advances to the next channel.

To scan the remaining channels, press the START/STOP
button each time a channel is to be scanned. After the last
programmed channel is scanned the instrument reverts to the
first programmed channel and turns off the START/STOP

LED. At this point the step scan sequence may be activated

again by pressing the START/STOP button, if desired.

The previous steps 1 through 8, show a general procedure to

-get the Model 706 into a scanning sequence. Paragraph 2.5.4
shows how to use the different scan modes, how to
chain several Model 706s for an extended number of chan­nels and how to scan using different scanner cards.

2.5.4 Scanning Examples
Example 1 Manual Scan (Step Scan&If it is desired to

scan through the programmed channels manually the Model
706 can be programmed for the step scan mode. In the step
scan mode the programmed channels can be scanned (closed

for the programmed interval rate and then opened) one chan-

nel at a time. Upon the actuation of the START/STOP but­ton a single channel will be scanned. For this example we will
choose the following parameters.

1. First channel is 1.

2. Last channel is 10.

3. Interval time is 2 seconds.

4. Number of poles is 2.

5. Use the step scan mode.
Use the steps outlined in Table 2-6 to program the Model 706

for the preceding parameters. For the sake of simplicity we
will use the Model 7056 general purpose scanner card for this

example.

daisy

To stop the scanning sequence and reset the Model 706 to
the programmed first channel simply press the RESET but­ton.

.-

Example 2 Single Scan-In the single scan mode all the
programmed channels are scanned sequentially one time
upon the actuation of the START/STOP button. The single
scan sequence operates as follows:

1. The START/STOP LED turns on.

2. The programmed first channel is closed for the pro-

grammed interval rate and then opened.

3. The Model 706 then advances to the next channel, closes

it for the programmed interval rate and then opens it.

4. This sequence is repeated up to and including the pro-

gammed last channel. At this point the Model 706 reverts
to the programmed first channel and turns off the

START/STOP LED.

5. The single scan sequence is now complete.
To help illustrate a single scan sequence we will choose the

following parameters. For the sake of simplicity we will use
the Model 7056 general purpose scanner card.

1. First channel is 5.

2. Last channel is 25.
3: Interval time is 0.5 seconds.

Table 2-6. Step Scan Example

Step Action Comments

1 Install the Model 7056 General Purpose

Scanner Card into slot 1 of the Model

706.

2 Select appropriate line voltage and turn

on the Model 706.
3 Press PRGM, 6.
4

Press 2, ENTER.

Press 0, 0, 1, FIRST.

i

Press, 0, 1, 0, LAST.

7

Press INTERVAL, 0, 0, 2,0,0,0, ENTER.

8 Press CHANNEL, RESET.
9 Press START/STOP.

Refer to paragraph 2.2.2.

Selects PROGRAM 6.
Selects the 2-pole mode, refer to para­graph 2.9 for more information about
front panel programs.
Programs channel 1 as the first channel.
Programs channel 10 as the last channel.
Programs the interval time for two seconds.
Selects the channel mode for display and
reverts to the first channel.
Initiates the step scan mode.

.

4. Number of poles is 2.

5. Use single scan mode.
Use the steps outlined in Table 2-7 to program the Model 706

for the preceding parameters.
Upon the actuation of the START/STOP button in step 10,

channel 5 is closed for 0.5 seconds (programmed interval
rate) and then opens. The Model 706 advances to the next
channel and closes it for the programmed interval rate and

then opens it.
The sequence continues up to and including the last pro-

grammed channel. At this point the Model 706 reverts to the
programmed first channel and turns off the START/STOP
LED. The single scan sequence is now complete.

Pressing the START/STOP button during a single scan se­quence stops the scan at the presently displayed channel.
The channel remains closed and turns off the START/STOP

LED. To continue the scanning sequence from the presently
displayed channel press the START/STOP button.

To stop the scanning sequence and reset the Model 706 to
the programmed first channel (which is 5 in this example)
simply press the RESET button.

Example 3 Continuous Scan-In the continuous scan
mode the scanning sequence described in example 2 repeats
continuously until at least one of the following conditions are
met:

1. Power is interrupted.

2. During the sequence, the START/STOP button is

pressed.

3. RESET button is pressed.

4. PRGM button is pressed.

5. DATE button is pressed.

6. TIME button is pressed.

7. CHANNEL button is pressed.
In the continuous scan mode all the programmed channels

are scanned sequentially and the scan sequence is repeated
continuously. The continuous scan is started by pressing the

START/STOP button and it operates as follows:

1. The START/STOP LED is turned on.

2. The programmed first channel is closed for the programm-

ed interval rate and then opened.

3. The Model 706 then advances to the next channel, closes

it for the programmed interval rate and then opens it.

4. This sequence is repeated up to and including the pro-

grammed last channel. At this point the Model 706 reverts
to the programmed first channel and repeats the sequence
continuously.

To help illustrate a continuous scan sequence we will choose
the following parameters. For the sake of simplicity we will
use the Model 7056 general purpose scanner card.

1. First channel is 1.

2. Last channel is 100.

3. Interval time is 0.3 seconds.

4. Number of poles is 2.

5. Use continuous scan mode.

Use the steps outlined in Table 2-8 to program the Model 706
for the preceding parameters.

-

Ster, 1 Action

Install the three Model 7056 scan- Refer to paragraph 2.2.2.

1.
ner cards into slots 1, 2

* and 3 of the Model 706.

Select appropriate line voltage

2

and turn on the Model 706.
Press PRGM, 6. Selects PROGRAM 6.

3

Press 2, ENTER. Selects the 2-pole mode. Refer to paragraph 2.9 for

4

Press 0, 0, 5, FIRST. Programs channel 5 as the first channel.
Press 0, 2, 5, LAST. Programs channel 25 as the last channel.

z

Press INTERVAL, 0, 0, 0, 5, Programs the interval time for 0.5 seconds.

7

0, 0, ENTER.
Press CHANNEL, RESET. Turns on the CHANNEL LED, selects the channel

8

Press SINGLE. Selects the single scan mode and turns on the

9

Press START/STOP.

10

Table 2-7. Single Scan Example

I Comments

more information concerning front panel programs.

mode for display and resets to the programmed first
channel.

SINGLE LED.
Initiates the single scan sequence.

2-9

Table 2-9. Continuous Scan Example

Step

1

Action
Install 10 Model 7056s into slots

Comments
Refer to paragraph 2.2.2.

I-IO of the Model 706.

2

Select appropriate line voltage

and turn on the Model 706.

3

Press PRGM, 6.

4

Press 2, ENTER.

Selects PROGRAM 6.
Selects the 2-pole mode. Refer to paragraph 2.9 for more

information about front panel programs.

5

Press 0, 0, 1, FIRST.

6

Press 1, 0, 0, LAST.

7

Press INTERVAL, 0, 0, 0, 3,

Programs channel 1 as the first channel.
Programs channel 100 as the last channel.
Programs the interval time for 0.3 seconds.

0,0, ENTER.

8

Press CHANNEL, RESET.

Turns on the CHANNEL LED, selects the channel
mode for display and resets to the programmed first
channel.

9

Press CONTINUOUS.

Selects the continuous scan mode and turns on the
CONTINUOUS LED.

10

Press START/STOP.

Initiates the continuous scan sequence.

Upon the actuation of the START/STOP button in step 10,
channel 1 is closed and the START/STOP LED is turned on.
Channel 1 remains closed for 0.3 seconds (programmed inter-

val rate) and then opens. Model 706 advances to the next

channel and closes it for the programmed interval rate and

then opens it.

This sequence continues up to and including the last pro­grammed channel. At this point the Model 706 reverts to the
programmed first channel and repeats this scan sequence
continuously.

Pressing the START/STOP button during a continuous scan
sequence stops the scan at the presently displayed channel.

The channel remains closed and the START/STOP LED

turns off. To continue the scanning sequence from the
presently displayed channel press the START/STOP button.

To stop the scanning sequence and reset the Model 706 to
the programmed first channel (which is 1 in this example)
simply press the RESET button.

Example 4 Daisy Chain Configuration-In a situation

where more than 100 channels are required the Model 706

can be connected to other Model 706 scanners to increase
the number of available channels. A total of five Model 706
scanners can be connected together to increase the number

of available channels to 500. The method of connection is
shown in Figure 2-4 and is referred to as a daisy chain con­figuration.

One of the Model 706 scanners is programmed (by user

choice) as the master control instrument of the configuration.
The other Model 706 scanners are programmed as the slaves.
As slaves, the front panel controls of these instruments are

locked out (not functional) except for the power switch, front
panel Program 90 and 91, The power switch is functional but
when power is cycled the slave instrument powers up to the
slave condition. The only method out of the slave condition is
to activate Program 90 or 91. For complete details concerning
front panel programs refer to paragraph 2.9.

In this example the master Model 706 will be programmed to
scan 500 channels. The equipment required for this example
is shown in Table 2-9. For the sake of simplicity we will use
Model 7056 general purpose scanner cards for this example.
To help illustrate this daisy chain example we will choose the
following parameters:

1. First Channel is 1.

2. Last channel is 500.

3. Interval time is 0.2 seconds.

4. Number of poles is 2.

5. Use continuous scan mode.

2-10

Table 2-9. Required Equipment for Daisy Chain Example

Description
Scanner Mainframes -

Scanner Cards General Purpose
Cables

Specification Mfg. Model Qty

Keithley 706 5
Keithley 7056 50

BNC to BNC Keithley 7051-5 5

Use the steps outlined in Table 2-10 to program the daisy
chain configuration for the preceding parameters.

Upon the actuation of the START/STOP button in step 13,
the continuous scan sequence starts from the progammed
first channel. The continuous scan mode operates in the
same manner as described in example 3. The only difference
is that this example will scan 500 channels and then repeat
the sequence continuously.

Pressing the START/STOP button during a continuous scan

Table 2-10. Daisy Chain Example

SteD Action

Install the Model 7056 scanner cards
into the Model 706 mainframes.
Set up the circuit shown in
Figure 2-4.
Select appropriate line voltage and
turn on the Model 706 scanners.
Program 4 Model 706 scanners as a
slave by pressing PRGM, 9, 2 on
each 706.
Select the remaining Model 706 as

5

the master of the configuration
by pressing PRGM, 9, 1.

Initiating front panel PROGRAM 92 locks up the
Model 706 front panel, except for the power
button, PROGRAM 90 and 91. The following
message is displayed while front panel PRO­GRAM 92 is activated.

Comments
Refer to paragraph 2.2.2.

Programs the Model 706 as slaves in the daisy
chain configuration.

Sets one Model 706 as the master control of the
daisy chain configuration.

NOTE

.-_

sequence stops the scan at the presently displayed channel.
The channel remains closed and the START/STOP LED
turns off. To continue the scanning sequence from the

presently displayed channel press the START/STOP button.

The first and last channels are not battery backed up in the

daisy chain configuration.
To stop the scanning sequence and reset the Model 706 to

the programmed first channel (which is 1 in this example)
simply press the RESET button.

On the master control 706 press

6

PRGM, 6.

7 Press 2, ENTER.

0, 0, 1, FIRST.

Press

8
9

10
11

5, 0, 0, LAST.

Press

INTERVAL, 0, 0,

Press
ENTER.
Press CHANNEL, RESET.

Press CONTINUOUS.
Press START/STOP.

-5LRl.E -

r

Selects PROGRAM 6. All programming will be done
on the master control 706 from this
step on.
Selects the 2-pole mode. Refer to paragraph

2.9 for more information concerning front panel
programs.
Programs channel 1 as the first channel.
Programs channel 500 as the last channel.

0, 2, 0,

Figure 2-4. Daisy Chain Configuration

0,

Programs the interval time for 0.2 seconds.
Turns on the CHANNEL LED, selects the

channel mode for display and resets to the
programmed first channel.
Selects the continuous scan mode and turns
on the CONTINUOUS LED.
Initiates the continuous scan mode sequence.

J

The display in the daisy chain configuration includes an addi­tional digit to accomodate up to 500 channels, 1000 channels

in l-pole mode. The display is shown as follows:

NOTE
Channels 1, 11 and 21 are the temperature
references for the cards.

I ml If 01

L I

NOTE
Scanning at a high rate of speed in the daisy
chain configuration may not show the scanned
channels on the mainframe’s display.

Example 5 Temperature Scan-With the Model 7057A
thermocouple scanner card, the Model 706 can scan
temperature points. Since the Model 7057A combines the
functions of a thermocouple scanner and uniform
temperature reference it is especially useful for scanning
thermocouples. The input terminals are #lO alloy copper set

in an isothermal block to minimize temperature differences. A
thermistor sensor within the isothermal block is used with a

bridge network located on the Model 7057A. The
temperature of the heat sink is used to calculate the corrected
thermocouple output. The output voltages of each thermo­couple must be converted to temperature (OC or OFI using ap-

propriate thermocouple tables or polynominal equations.
These equations and tables are provided in the Model 7057A

Instruction Manual.

In this example the Model 706 will be programmed to scan 25
separate temperatures. The following parameters will be pro-

grammed into the Model 706.

1. First channel is 1.

2. Last channel is 25.

3. Number of poles is 2.

4. Interval time is 3 seconds.

5. Use the continous scan mode.
Table 2-11. Temperature Scan Example

Use the steps outlined in Table 2-11 to program the Model

706 for the preceding parameters.

As you can see this temperature scan example is quite similar
to the continuous scan example (example 3). The only ap­preciable difference is the type of scanner card used in each
example. Except for specified values of the parameters
selected, front panel operation is similar in all scanning se­quences. _

For more detailed information concerning temperature scans
refer to the Model 7057A Instruction Manual.

Example 6 Low Current Scan-With the Model 7058 in-

stalled, the Model 706 is capable of scanning currents in the

range of picoamps. The Model 7058 is a low current scanner

card that is field installable in the scanner mainframe. The

Model 7058 is designed to introduce a minimum of offset cur-

rent (c IpA), while guarding ensures that high isolation

(10153) is maintained between input signals.

The actual measurement of the low current should be done
with a high quality electrometer such as the Model 614 or

Model 619. A high quality picoammeter such as the Keithley

Model 480 could also be used. All three of these instruments
are capable of measuring in the range of picoamps with high
accuracy. To measure such low currents a number of

measurement parameters such as, input impedance, cabling,

measuie~ment~ configuration, a&.,- must be taken into con;
sideration. This example does not attempt to give instructions
on low current measurement, the instruction manuals pro­vided with each of the previously mentioned electrometers

2-12

Step

1

2
3

4

9

10

Action
Install a Model 7057A into

slots 1, 2 and 3 of the
Model 706.
Select appropriate line voltage
and turn on the Model 706.

Press PRGM, 6.
Press 2, ENTER.

Press 0, 0, 1, FIRST.
Press 0, 2, 5, LAST.
Press INTERVAL, 0, 0, 3, 0,

0, 0, 0, ENTER.

Press CHANNEL, RESET.

Press CONTINUOUS.
Press START/STOP.

Comments
Refer to paragraph 2.2.2.

Selects PROGRAM 6.
Selects the 2-pole mode, refer to paragraph

2.9 for more information concerning front
panel programs.
Programs channel 1 as the first channel.
Programs 25 as the last channel.

Programs the interval time for three seconds.

Turns on the CHANNEL LED, selects the
channel mode for display and resets the
instrument to the first channel.
Turns on the CONTINUOUS LED and selects
the continuous scan mode.

Initiates the continuous scan mode sequence.

and picoammeter give step by step instructions on how to
measure low currents accurately.

In this example, the Model 706 will be programmed to scan
37 low current sources. Also, the following parameters will be
programmed into the Model 706.

1. First channel is 1.

2. Last channel is 37.

3. Interval time is 2 seconds.

4. Number of poles is 2.

5. Use single scan mode.
Use the steps outlined in Table 2-12 to program the Model

706 for the preceding parameters.

As you can see this low current scan example is similar to the
other scanning examples. The only appreciable difference is

Table 2-12. Low Current Scan Example

the type of scanner card used in each example. Except for the
specified values of the parameters selected, front panel
operation is similar in all scanning sequences.

For more detailed information concerning low current scans
refer to the Model 7058 Instruction Manual.

2.6 FRONT PANEL CLOCK OPERATION
The CLOCK group on the front panel contains the TIME and

DATE buttons. The clock continues to run after the Model
706 is turned off. This is because the clock’s power circuitry
is backed up by battery BTlOl. The time is shown in a 24
hour display-format. To display the time mode simply press
the TIME button. To set the time, use the steps outlined in
Table 2-13.

Step Action

Install a Model 7058 into slots

1

1, 2, 3 and 4 of the Model

706.
Select appropriate line voltage and

2

turn on the Model 706
Press PRGM, 6.

3

Press 2, ENTER.

4

Press 0, 0, 1, FIRST.

5

Press 0, 3, 7, LAST.

6

Press INTERVAL, 0, 0, 2, 0, 0,

7

0, ENTER.

Press CHANNEL, RESET.

8

Press SINGLE. Turns on the SINGLE LED and

9

Press START/STOP. Initiates the single scan mode sequence.

10

SteD 1 Action I Comments

2

*Pressing the TIME button during a scan sequence stops the sequence,

turns on the TIME LED and selects the time mode for display.

Comments
Refer to paragraph 2.2.2.

Selects PROGRAM 6.
Selects the 2-pole mode, refer to para­graph 2.9 for more information concerning

front panel programs.

Programs channel 1 as the first channel.
Programs channel 37 as the last channel.
Programs the interval time for two seconds.

Turns on the CHANNEL LED, selects the

channel mode for display and resets the
instrument to the first channel.

selects the single scan mode.

Table 2-13. Setting the Time

I

1 Press TIME”.

Selects the time mode for
display and turns on the
TIME LED.

Press the DATA buttons (O-9) Set the time for 7:30 A.M.
that correspond to the desired
time. For example, to set the
time for 7:30 A.M. press
0, 7, 3, 0, 0, 0, ENTER.

. .

2-13

Upon the actuation of the ENTER button, the time is set to

7:30 A.M. As another example, set the time to 7:30 P.M. by

pressing 1, 9, 3, 0, 0, 0, ENTER.

To display the DATE mode, simply press the DATE button.
The date is displayed in one of two formats. The formats are
the American date format and the International date format.
These formats are described in paragraph 2.9.2. The formats
are selected exclusively by front panel Program 1. Refer to
paragraph 2-9 for complete details concerning the front panel
programs. To set the date, use the steps outlined in Table

2-14.
As another example, set the date to August 18th for the inter-

national date format by pressing:

1. PRGM, 1 (Selects front panel Program 1 for display.)

2. 1, ENTER. (Selects the international date format.)

3. 1,8,0, 8, ENTER. (Enters 18.08 for the date August 18th.)

NOTE

If upon power up the Model 706 displays the

slave or no loop message (refer to paragraphs

2.9.11 and 2.9.12) activate Program 90 return
the Model 706 to normal operating conditions.
To activate Program 90, press PRGM 9,0.

To identify the previous state of the functions that are not
affected by power up, simply activate the desired function.
When the function is activated the previous state for that
function is displayed. Refer to paragraph 2.5.1 for informa­tion concerning the actuation of the desired function.
Refer to Table 2-2 for power up default conditions.

2. CHANNEL-The CHANNEL button selects the channel
mode for display. The channel number is displayed on the
front panel as a two digit number, except in the daisy chain
or matrix mode. Upon power up the Model 706 reverts to
the channel mode.

2.7 DETAILED FRONT PANEL CONTROLS DESCRIP­TION

1. POWER ON/OFF-The On/Off switch operates on the
push-push principle. Depressing this button turns the in­strument on. Once the instrument is on, pressing (releas­ing) this button turns the instrument off. When the Model
706 is turned on it goes through a power up sequence as
outlined in paragraph 2.3. When the power up sequence is
complete the Model 706 displays the following:

[ Cl1 F lx-

where:
01 = Channel Number One

F = First Channel*

o = Channel Open

*If channel 1 was previously programmed as the first

channel, last channel or both, it is displayed as such. This

is because the first and last functions are battery backed up

and not affected by power up.

Table 2-14. Setting the Date

Pressing the CHANNEL button while the Model 706 is in

the channel mode increments the channel number by one.

Actuation of the clock, date, PRGM, single, continuous,
or interval functions takes the Model 706 out of the chan­nel mode. Actuation of the reset function during any of the

front panel programs except Programs 90, 91, 92 and 99

reverts the Model 706 to the channel mode.

3. OPERATION-The OPERATION group consists of four
function buttons: FIRST, LAST, CLOSE and OPEN. The
buttons are described as follows:

CLOSE-Upon actuation of the close function the

present!y disp!ayed channe! rt!asesi !f fhF( prasent!y
displayed channel is already closed, pressing the CLOSE
button has no effect on the channel. When the presently

displayed channel is open and the CLOSE button is press­ed the open and close digit (furthest digit on the right of
the display) changes to a c and that channel is closed.
Refer to the following display.

iYnT--&

Open and Close Digit

o = Channel Open

c = Channel Closed

2-14

SteD 1 Action I Comments

Press DATE.*

1

Selects the date mode for display and turns on
the DATE LED.

Press the DATA buttons (O-9)

2

that correspond to the desired

For example, to set the date to August 18th

for the American date format follow steps 3,

date. 4 and 5.

3

Press PRGM, 1.
Press 0, ENTER.

4
5

Press 0: 8, 1, 8, ENTER.
..­“Pressing the DATE button during a scan sequence stops the sequence, turns on the DATE LED

_ -_--.

Selects front panel PROGRAM 1 for display.
Selects the American date format.
Enter 08.18 for the date August 18th.

and selects the date mode for display.

To ensure reliable performance, do not simultaneously close
more relays than the mainframe power supply can handle. The
closure limit depends on factors such as the drive current of
each relay, temperature, and ventilation.

Pressing the-FIRST button designates the

channel and the display format is as follows:

channel as first

Table 2-I 5 lists the maximum current available from the main­frame power supply for energizing relays under different operat-

ing conditions. To find the maximum number of simultaneous
relay closures, divide the current listed by the specified drive

current per relay. Remember that some cards energize two re-

lays for each channel (e.g., Models 7063 and 7067).

Table 2-15. Maximum Relay Drive Current from

Mainframe

Rack-

Bench-top

(Louvers between between

Temp.

23’ C 4.3A
50” c 3.3A

OPEN - Upon actuation of the open function the presently dis­played channel opens. If the presently displayed channel is al-

ready open, pressing the OPEN button has no effect on the
channel. When the presently displayed channel is closed and
the OPEN button is pressed the open and close digit (furthest
digit on the right of the display) changes to an o and that channel

is opened. Refer to the following display.

o=

Channel Open

c=

Channel Closed

Close and open for each channel remains valid
even when not viewing the channel or the display.

FIRST - Upon actuation of the FIRST button the presently dis­played channel is designated as the first channel of a multi­channel configuration. If the presently displayed channel has al­ready been specified as the first channel, pressing the FIRST
button has no effect on the channel or the display. If the pres­ently displayed channel has not been designated as the first

channel, the display format is as follows:

unobstructed) scanners) scanners)

mount mount

(1” space

4.3A

2.3A

Open and Close Digit

NOTE

Rack-

(No space

4.3A

1.3A

where:
01 = Present Channel

F = First Channel
o =’ Channel Open

There are a number of ways to change the designated first
channel they are listed as follows:

A.

Select the desired new channel then press FIRST.

B. Activate Program 99.

C. Activate Program 90.

NOTE
Powering the unit down will not change the desig­nated first channel.

LAST - Upon actuation of the LAST button the presently dis­played channel is designated as the last channel of the multi­channel configuration. if the presently displayed channel has al­ready been specified as the last channel, pressing the LAST
button has no effect on the channel or the display. If the pres-

ently displayed channel has not been designated as the last

channel, the display is as follows:

cl

--I

where:
01 ,= Present Channel

o = Channel Open

Pressing the LAST button designates the channel as last chan­nel and the display format is as follows:

I
/ 10 L, 01

where:

10 = Present Channel

L = Last Channel

o = Channel Open

There are two ways of changing the designated last channel

they are listed as follows:

where:
01 = Present Channel

o = Channel Open

+

2-15

A. Select desired new channel and press LAST.
B.

Activate Program 99.

NOTE

Powering the unit down will not change the

designated last channel.

If the presently displayed channel is designated as the first

and last channel the display format is as follows:

I IU FLol

I

where:

- -30 = Present Channel
F = First Channel
L = Last Channel

o = Channel Open

4. CONTROL-The CONTROL group of buttons consist of
the RESET button and the INTERVAL button. The buttons
and their functions are described as follows:

RESET-Actuation of the RESET button opens all chan­nels of the Model 706 and reverts the display to the
designated first channel. Actuating the RESET button dur­ing a single or continuous scan mode sequence stops the

scan sequence, opens all channels and reverts the display
to the designated first channel. The RESET button is inac­tive in the time, date, interval and Programs 8, 90, 91, 92
and 99.

INTERVAL-The INTERVAL button selects the program-

med interval time for display. The interval time is the pro­grammed time each channel is closed when using the step,
single or continuous scan mode. The interval time ranges
from 000.010 seconds to 999.999 seconds. Upon the ac­tuation of front panel Program 99 the interval time is
reverted to the default condition of 000.010. Powering the

unit down will not change the programmed interval time.

. There are two ways the interval time can be changed and

they are as follows:
A. Activate Program 99 (resets to 000.010).
B. Press the INTERVAL button and then press the ap-

propriate number from 000.010 to 999.999. Press
ENTER.

5. DATA-The DATA group of buttons consist of the O-9,
CANCEL and ENTER buttons. They are described as

follows:

I

O-g-The O-3 data keys allow entry of numerical data onto

the display. The O-9 keys can be used to enter numerical

constants on the display for certain functions such as inter­val time, channel number, front panel programs, time and
date.

ENTER-Upon actuation, the ENTER button loads the
displayed data for channel number, interval time, time,
date and program modes into the Model 706. In the pro­gram mode, the ENTER button initiates the selected pro­gram (O-7) after the necessary data is entered onto the
display.

CANCEL-During the entry of data (C segment cursor is

flashing) the CANCEL button cancels the present display
and- reverts the instrument to the previous display. The

CANCEL button is functional only when entering data on-

to the display in the channel, interval, time, date and pro­gram modes.

Refer to Table 2-16 for an example of the CANCEL button
function.

In Table 2-16 the interval display mode is selcted and a 120
second interval time is entered onto the display. For some
reason or other the interval time in step 2 is an error so the
CANCEL button was pressed to revert the display to the
previously programmed interval time.

6. SCAN-The SCAN group of buttons consists of SINGLE,
CONTINUOUS, and START/STOP buttons. These three

buttons select the different scan modes and are described
as follows:

CONTINUOUS-Actuation of the CONTINUOUS button

selects the continuous scan mode and turns on the con­tinuous LED. The continuous scan mode allows the user to

scan through the programmed channels at the programm-

ed interval rate, continuously. The continuous scan mode
is initiated upon the actuation of the START/STOP button
or upon receiving the appropriate external trigger pulse.

Pressing the START/STOP button during a continuous
scan sequence stops the scan at the presently displayed
channel. To continue the scan sequence simply press the
START/STOP button.

2-16

step

1

2
3

Table 2-16. CANCEL Function Example

Action Comments
Press INTERVAL.

Press 1, 2, 0, 0, 0, 0.
Press CANCEL.

Selects interval display mode and turns on
the INTERVAL LED.
Enters 120 second interval time on the display.
Reverts the interval time data of step 2 to

the previously programmed interval time.

SINGLE-Actuation of the SINGLE button selects the
single scan mode and turns on the single LED. The single
scan mode allows the user to scan through the programm­ed channels at the programmed interval rate, one time.

TIME-The TIME button selects for display the 24 hour
time clock. The format showing 2:45 pm is as follows:

~W5.UUl

The single scan mode is initiated upon the actuation of the
START/STOP button or upon receiving the appropriate
external trigger pulse.

Pressing the START/STOP button during a single scan se­quence stops the scan at the presently displayed channel.

To continue the scan sequence simply press the

START/STOP button.

-­START/STOP-The START/STOP button is an alter-

nate action control that has three functions. The three

functions are the start function, stop function and the step
scan mode. These functions are described as follows:

A. START-The start function of the START/STOP but-

ton initiates the selected scan mode. When all the
parameters (interval time, first and last channels, scan
mode, etc.1 of a multi-channel configuration have been
programmed and the user is ready to scan the chan­nels, press the START/STOP button to initiate the
scan sequence. During the scan sequence the
START/STOP LED is activated.

B. STOP-The stop function of the START/STOP button

stops the previously initiated scan sequence. That is,

pressing the START/STOP button during a scan se-

quence stops the sequence at the presently displayed

channel and turns off the START/STOP LED. The
STOP function is active only during a scan sequence.

C. STEP-The step scan mode allows the user to manual-

ly step through the programmed channels. The step
scan mode is selected by pressing the channel button,
programming the interval rate and pressing the

START/STOP button. When the interval rate has been
programmed and the user is ready to manually scan the
channels, press the START/STOP button to scan one

- ~~
channel.

Upon initiating the step scan mode the START/STOP

LED turns on, the presently displayed channel is closed
for the programmed interval rate, the channel is then
opened and the START/STOP LED turns off. At this
point the Model 706 advances to the next channel and
then stops.

To scan the next channel press the START/STOP but­ton and the Model 706 repeats the same sequence with
the presently displayed channel.

7 .CLOCK-The CLOCK group of buttons consist of the

TIME and DATE buttons. The clock (time and date) con-

tinues to run after the instrument is powered down

because the clock circuitry is backed up by battery BTlOl .

The two buttons are described as follows:

The time can be set by pressing the TIME button, entering
the appropriate time onto the display and then pressing the

ENTER button. Note that the time 28:00:00 to 33:59:59

can be entered. It is invalid but it can be entered.

DATE-The DATE button selects the date mode for
disolav. The date disolav has two formats. The formats
showing June 17th are a’s follows:

American Date Format /I ’
International Date Format 1
The formats are selected by front panel Program 1. Refer

to paragraph 2-9 for more information concerning front
panel programs. The date can be set by pressing the DATE
button, entering the appropriate date onto the display and

then pressing ENTER. Refer to paragraph 2.6.

8. PRGM-The PRGM button when pressed shows a
display that prompts the user to select one of the 15 front
panel programs. Refer to paragraph 2.9 for complete
details and examples of the front panel programs.

9.

IEEE Indicators-The IEEE bus indicators (TALK,
LISTEN and REMOTE) identify the present status of the
IEEE-488 bus. The indicators are described as follows:

TALK-The TALK LED when lit indicates that the Model
706 is in the talk mode. The Model 706 does not have to
be in the remote mode for it to be in the talk mode.

LISTEN-The LISTEN LED when lit indicates that the
Model 706 is in the listen mode. The Model 706 must also

.be in the remote mode for it to be in the listen mode.

REMOTE-The REMOTE LED when lit indicates that the
Model 706 is in the remote mode.

2.6 DETAILED REAR PANEL DESCRIPTION

1. CARD SLOTS-Each card slot on the Model 706 rear
panel can accomodate one scanner card. There are a total

of 10 card slots. That is, the Model 706 can accomodate 10
scanner cards. The Model 706 with 10 scanner cards has

up to 100 2-pole channels. Refer to paragraph 2.2.2 for in-

structions on how to remove or install the various scanner
cards.

2. EXT. TRIGGER-The external trigger is a BNC connector
that initiates the selected scan mode (single, step or con­tinuous) in the same manner as the START/STOP button.
The input trigger pulse must be a negative going lTL level

pulse with a minimum duration of met. The selected scan
mode is initiated upon the negative transition of the pulse.

I- / 7 D b

2-17

This feature can be used to trigger the Model 706 into the
selected mode using another instrument.

3. CHANNEL READY-The CHANNEL READY output is a
BNC output connector that provides a negative going lTL

level pulse with a duration of greater than 10pec at the
completion of the programmed settling time. This features
can be used to inform another instrument (DMM, Source,
etc.) that the present channel settling time is completed.

4. ALARM/SERIAL IN-The ALARM/SERIAL IN connec-

tor has two functions. The alarm out function and the

serial in function. They are described as fokows:

ALARM-The alarm function outputs a negative going
TTL level pulse with a duration of greater than 10wec. This

‘pulse appears once upon reaching the programmed alarm

time. The alarm time can be programmed by front panel
Program 7. When the alarm time is set to 00.00.00 the
pulse does not appear. The programmed alarm time is set

to 00.00.00 when power to the instrument has been

cycled. Refer to Table 2-3.

SERIAL IN-The serial in function is used in a daisy chain
configuration where the ALARM/SERIAL IN connector is
connected to the SERIAL OUT connector of another
Model 706. Refer to example 4 of paragraph 2.5.4.

5. SER. OUT-The SER. OUT connector is a BNC output

connector that provides a connection to another Model
706 for a daisy chain configuration. The SERIAL OUT con­nector is applied to the ALARM/SERIAL IN connector of
another Model 706. Refer to example 4 of paragraph 2.5.4.

6. DIGITAL l/O-The DIGITAL I/O port consists of 16

digital input and output lines along with four lines that are

+ 5V and IEEE common. Eight of the I/O lines can be used
for inputs and eight can be used for outputs. The outputs
will drive one TTL load and the inputs are TTL compatible.

For more information concerning the digital I/O port refer

to paragraph 3.5.8 step 15.

7. IEEE-488 INTERFACE-The IEEE bus connector pro­vides bus connection to the Model 706. The connector

mates with the Keithley Model 7008-3 and 7008-6 cables.

For more detailed information concerning the IEEE con-

nector refer to paragraph 3.3.

8. LINE FUSE-This is the line power fuse and it is rated

as specified in Table 5-2.

9. LINE RECEPTACLE-The line power receptacle mates
with a three wire line cord which provides connections to

line voltage. For correct line voltage selection refer to
paragraph 5.3.

2.9 FRONT PANEL PROGRAMS

15 internal proSCams of the Model 706. The programs are ac-

tivated by pressing the PRGM button along with the button

representing the appropriate program number. The programs
do a number of various tasks which are summarized in Table

2-17.

Program Notes

1.

Each program is entered by pressing the PRGM button

followed by the desired program number.

2.

Pressing the PRGM button selects the program mode and

the following is displayed:

r--TzTj --

As you have noticed, the question mark is flashing. This is
prompting the operator to enter the desired program
number (refer to Table 2-17). After entering the program
number the Model 706 goes into the program selected.

Then the display prompts the operator to enter numerical

data. Numerical data varies with each program.

3.

New programs may be entered without clearing a program
that is presently running. To do so, press the PRGM but­ton followed by the desired program number.

4.

Data is entered into the digit whose “C” segment (cursor)
is flashing by pressing the desired number button. The
“C” segment of a display is shown as follows:

1-G +fment

As each digit is entered, the cursor moves one place to the

right until the last digit on the right is reached. Then it is
cycled to the first digit on the left.

Only as many significant digits as necessary need to be

5.
entered. The Model 706 will complete the constants with
trailing zeroes where necessary.

Invalid keys will be ignored. If an invalid key is pressed the

6.
blinking “C” segment (cursor) remains at the current digit.

If an incorrect digit is entered, the complete constant must

7.
be reentered. The new value may be entered by cycling

the display around to the beginning. To do this, repeatedly

press one of the number buttons.

If too many digits are entered, the display begins again at

8.
the first digit on the left. All the digits in the constant must
then be entered again. This applies only to Programs 0,2,
3, 6 and 7.

Once all the digits of the desired constants are shown on

9.
the display, the constant is entered into the program by
pressing the ENTER button. This applies only to Programs
0 through 7.

This section contains instructions necessary for operating

2-18

the