DOCUMENT RESUME

ED 135 392 IB 004 503

AUTHOR.' Kargo, Donald W.; Steffen, Dale A.TITLE Performance Training Carrelfor Electronics

Principles Course.INSTITUTION Air Force Human Resources Lab., Lowry AFB, Colo.

Technical Training Div.SPONS AGENCY Advanced Research Projects Agency (DOD) , Washington,

D.C.; Air Fcrce Human Resources Lab., Brooks AFB,Texas.

REPORT NO APHRI-TR-76-62 (I)PUB DATE Sep 76CCNTRACT F41609-75-C-0031NOTE 22p.; For related documents see IR 004 503-504.

EDRS PRICE MF-$0.83 BC-$1.67 Plus Postage.DESCRIPTORS *Autoinstructional Aids; *Computer Assisted

Instruction; *Computer Graphics; *Display Systems;Input Output Devices; Ban Machine Systems; ProgramedMaterials; Programing Languages; Teaching Machines;,*Technical Education

IDENTIFIERS PLATO

ABSTRACTThis manual provides documentation for the design;

construction, and operation of an interactive electronics trainingpanel developeca for a computer assisted performance training carrel.The panel is a plu-in module designed to simulate electroniccircuitry and a PMS-6 multimeter as required for a troubleshootingfundamentals lesson in an Air Force Electronics Principles course.Five schematic panels were developed for simulation of all circuitryused in the lesson. (Author/WBC)

************************************************************************ DocwOns acquired by ERIC include many informal unpublished ** material:L .11,ct available from other sources. ERIC makes every effort ** to oktain the best copy available. Nevertheless, items of marginal ** reproducibility are often encountered and this affects the quality ** of the micrcfiche and hardcopy reproductions ERIC makes available ** via the uac Document Reproduction Service (EDRS). EDRS is nbt ** responsible for the quality of the original document. Reproductions ** supplied by EDRS are the best that can be made from the original. ************************************************************************

AFHRL-TR-76-62(1)

AIR FORCE

A

'U.S. DEPARTMENT OF HEALTH.

EDUCATION & WELFARENATIONAL INSTITUTE OF

EDUCATION

THIS DOCUMENT HAS BEEN REPRO.OUCE0 EXACTLY AS RECEIVED FROMTHE PERSON OR ORGANIZATION ORIGIN.ATING IT POINTS OF VIEW OR OPINIONSSTATED 00 NOT NECESSARILY REPRE.SENT OFFICIAL NATIONAL INSTITUTE OFEOUCATION POSITION OR POLICY.

?ERFORMANCE TRAINING CARREL FORELECTRONICS PRINCIPLES COURSE

By

Donald W. KargoDale A. Steffen

Denver Research InstituteUniversity of Denver

Denver, Colorado 80210

TECHNICAL TRAINING DIVISIONLowry Air Force.Base, Colorado 80230

September 1976Interim Report for Period 15 February 1975 5 January 1976

Approved for public release; distribution unlimited.

LABORATORY

AIR FORCE SYSTEMS COMMANDBROOKS AIR FORCE BASE,TEXAS 78235

2

NOTICE

When US Government drawings, specifications, or other data are usedfor any purpose other than a definitely related', GovernmentProcurement operation, the Government thereby incurs noresponsibility nor any obligation whatsoever, and the fact that theGovernment may have formulated, furnished, or in any way suppliedthe said drawings, specifications, or other data is not to be regarded byimplication or otherwise, as in any manner licensing the holder or anyother person or corporation, or conveying any rights or permission tomanufacture, use, or sell any patented invention that may in any waybe related thereto.

This interim report was submitted by Denver Research Institute,University of Denver, Denver, Colorado 80210, under contractF41609-75-C-0031, project 1121, with Technical Training Division, AirForce Human Resources Laboratory (AFSC), Lowry Air Force Base,Colorado 80230. Mr. Gary G. Miller, Instructional Technology Branch,was the contract monitor.

This report has been reviewed and cleared for open publication and/orpublic release by the appropriate Office of Inforniation (01) inaccordance with AFR 190-17 and DoDD 5230.9. There is no objectionto unlimited distribution of this report to the public at large, or byDDC to the National Technical Information Service (NTIS).

This technical report has been reviewed and is approved.

MARTY R. ROCKWAY, Technical DirectorTechnical Training Division

Approved for publication.

DAN D. FULGHAM, Colonel, USAFCommander

3

UnclassifiedSaCURITY CLASSIFICATION OF THIS PAGE (When Data Entered)

REPORT DOCUMEt4TATION PAGEREAD INSTRUCTIONS

BEFORE COMPLETING FORM

1. REPORT NUMBERAFFIR L-T R-76-62(I)

2. GOVT ACCESSION NO. 3. RECIPIENT'S CATALOGNUMBER

4. TITLE (and Subtitle)

PERFORMANCE TRAINING CARREL FOR

ELECTRONICS PRINCIPLES COURSE

S. TYPE OF REPORT a PERIOD COVERED

Interim15 February 1975 5 January 1976

6. PERFORMING ORG. REPORT NUMBER

7. AUTHOR(*)

Donald W. KargoDale A. Steffen

8. CONTRACT OR GRANT NUMBER(e)

F41609-75-C-003 I

9. PERFORMING ORGANIZ ATION NAME AND ADDRESS

Denver Research InstituteUniversity of Denver .Denver, Colorado 80210

10. PROGRAII ELEMENT, PROJECT, TASKAREA A WORK UNIT NUMBERS

62703F11210214

I I. CoNTROLLING OFFICE N AME ANDADDRESS

HQ Air Force Human Resources Laboratory (AFSC)Brooks Air Force Base, Texas 78235

12. REPORT DATESeptember 1976

13. NUMBER OF PAGES

18

14. MONITORING AGENCY NAME & ADDRESS(H differentfrom Controlling Office)

Technical Training DivisionAir Force Human Resources Laboratory fLowry Air Force Base, Colorado 80230

15. SECURITY CLASS. (of this report)

Unclassified

15e. DECLEAE

SSIFICATION/DOWNGRADINGSCHOUL

16. DISTRIBUTION STATEMENT (ofthla Report)

Approved for publk'release; distribution unlimited.

17. DISTRIBUTION STATEMENT (of the abstract entered InBlock 20, if different from Report)

_ --

18. SUPPLEMENTARY NOTES

This research was parlially funded by Advanced ResearchProjects Agency, 1400 Wilson Boulevard, Arlington,

Virginia 22209.

19. KEY WORDS (Continue on reverse aide if necessary and identifyby block number)

computer simulated training.

performance trainingperformance training carrels

20. ABSTRACT (Continue on reverse side if necessary and identifyby block number)

A prototype performance training carrel wasdeveloped to demonstrate a computer managed learning

enSrironment. This report describes the simulation panel developed as a part ofthe carrel. The panel is a plug-in

module designed to provide simulation of electronic circuitryand a PSM-6 multimeter as required for a

troubleshooting fundamentals le ...on in an Air Force Electronics Principles course.

4

D FORM14I JAN 73

EDITION OF 1 NOV 6S IS OBSOLETE UnclassifiedSECURITY CLASSIFICATION OF THIS PAGE (When Data Entered)

SUMMARY

Problem

The objective of this effort was to evaluate a computer assisted performance training carrel which wasdeveloped in-house at the Air Force Human Resources Laboratory Technical Training 'Division, LowryAFB, Colorado. The evaluation was realized by using the training carrel to deliver the troubleshootingfundamentals lesson from the Lowry AFB Technical Training Center's Electronic Principles Course. Thismanual provides the documentation for the design, construction and theory of operation for the studentinteractive electronics training panel developed for use in the performance training carrel. The softwarenecessary to perform this task, and the subsequent course evaluation are described in AFHRL-TR-76-62(H)and AFHRL-TR-76-62(Ill).

Approach

The design approach was to develop a panel that would allow the user the greatest flexibility inimplementing the required simulations while maintaining complete hardware compatibility with the ex-isting carrel and its I/0 bus control system.

Results

The simulation panel was developed as a plug-in module that could easily be inserted into the carrel.

The module included all of the circuitry required to interface the performance carrel 1/0 bus, thesimulated PSM-6 inultimeter, and the interchangeable schematic boards which simulated basic electroniccircuitry. The multimeter and the schematic panel area comprised .the front face of the module. Trainingschematics with up to twenty-eight test points were accommodated. Under this effort, five schematicpanels were developed for simulation of all circuitry used in the troubleshooting lesson.

Conclusions

The system as developed has proved to be feasible for use in performance training and could beexpanded to simulate larger and more complex circuits used in higher level courses. The plug-in conceptpanel allows the carrel to be readily changed over to different instructional subjects.

5

TABLE OF CONTENTS

Page

. General Description 5

II. Circuit Analysi- 6

Block DinnmLogic Board 6

Simulated PSM-6 I 3

III. Maint enance 15

References 15

LIST OF 1 LLUSTRATIONS

Figu rePage

Cable routing 5

Perforinance training panel 7

3 Meter board 8

4- Logic boardu

5 Meter D/A 14

Table

Data Words

Binary Conversion

LIST OF TABLES

3

6

Page

12

13

PERFORMANCE TRAINING CARREL FOR ELECTRONICS PRINCIPLES COURSE

I. GENERAL DESCRIPTION

The performanee training carrel simulation panel was developed to be installed in the performancetraining carrel that is undergoing test and evaluation at the Technical Training Division, Air Force HumanResources Laboratory, Lowry Air Force Base, Colorado. It is plugged into and held in place by two ITTInstamate connectors. A rear view of the simulator panel and associated cable routing is shown in Figure I.All of the electrical connections are made through the left-hand connector only. The panel is designed tooperate through the I/0 interface card (DRI EC-12674) of the PLATO IWPDP-11 I/0 bus line controlsystem. Its purpose is to simulate under computer control the multimeter and the instructional circuits thatare required for the completion of a particular module of the Electronic Principles Course now being taughtby the Department of Avionics Training. The software documentation is included in AFHRL-TR-76-62 (II).

TO TEST JACKS D L INSTAMATE

LOGICBOARD

(FRONT)

JIJ2J3

J5J6

METERBOARD

JIJ2

( FRONT)

SIMULATOR PANEL (REAR VIEW)

LOGIC BOARD J I TEST JACKSLOGIC BOARD J2 TEST JACKSLOGIC BOARD J3 METER BOARD J ILOGIC BOARD J4METER BOARD J2LOGIC BOARD J5 INSTAMATE 1/0 J ILOGIC BOARD J6 INSTAMATE I/0 J2

J2

J I

Figure 1. Cable routing

5

I/0 CARD

1:1-7-ri-riONT)

The main features of the panel include the simulated PSM-6 multimeter and the interchangeableschematic boards.

The simulated multimeter is'a real PSM-6 front panel and meter movement mounted in a cutout inthe simulator sub-panel. The entire meter circuitry has been replaced with the new circuits required tointerface the meter panel with the computers. This simulated PSM-6 millimeter is used in the same manneras a real meter would be used in troubleshooting real circuits.

A matrix of twenty-eight test jacks occupies most of the remaining sub-panel space. Any or all of thejacks can be used as test points on a "schematic board." The schematic boards are constructed of 3/16-inchplastic sheet with the schematics printed on an overlay.,of.,Scolchcal" photosensitive material. The testpoints used for a particular schematic are the only ones exposed when the board is installed in its operatingposition on the subpanel. A spring loaded clamp holds the boards in place on the sub-panel. When a boardis in place, a set of switches are activated which encodes the schematic number for use by the computers..

A simulated power switch SI and twO display lamps DSI and DS2, are located directly below the testjack matrix. These components are the physical counterparts of the symbols that appear on the schematic'boards. All of the schematic boards have the power switch and may or may not have DS1 and/or DS2. Thephysical switch and lamps are used in thc same manner as if they were mounted on the circuit boards inplace of their respective symbols.

, An additional display lamp is located directly above the meter. This lamp is labeled ON LINE and itsfunction is to show when the computer is polling the panel. Meter readings and lamp status are valid onlywhen the ON LINE lamp is on.

Power requirements are +5VDC and -±15 VDC. All of the power is supplied by the power supplie.,located in the I/0 bus line control system.

CIRCUIT ANALYSIS

Block Diagram

Figure 2 is a block diagram of the performance training panel logic. All of the circuits are containedon three circuit boards. A printed circuit board is mounted behind the meler panel. It is referred to as themeter board. Figure 3 shows the circuitry included on this board along with the associated switches,potentiometer, indicator lamps, etc. tha are miunted on the meter panel itself or on the sub-panel.

The logic board is a universal wirewrap circuit board mounted behind the test jack matrix on thesub-panel. Figure4 contains all of the circuitry of this board.

The circuitry used in generating the current to the meter for simulated meter deflections is containedon the "users" portion of the 1/0 interface card (DR1 EC-I2674).

Logic Board

The logic board will be discussed first. It contains most of the circuitry required to determine themeter probe positions, ohms adjust potentiometer position and the output multipleker. An output displayis included as an aid in checkout and troubleshooting of the board.

The meter probes are referred to as the red probe (positive) and the black probe (negative). The meterprobe position circuitry consists of counters, latches and gating required to continuously monitor the statusof the probes.

U I is a tinier (NE555) wired as a free running mil tivibrator. The frequency of oscillation is approxi-mately 10 kHz. The output of Ul is wired to the divide-by-sixteen binary counter (SN74161) at U2, whoseMSB output drives the flip-flop (SN7472) U3. The resulting divide-by-thirty-two binary outputs are used asthe inputs to the two oneof-sixteen decoders (SN74I 54) U4 and U5 and the two latches (9308) U6and U7. Outputs 3 throngh 15 of U4 and 0 through 14 of U5 are wired to the twenty-eight test jacks on theschematic sub-panel and provide the probe signals for the latching circuits. A possible thirty-two probepositions are available of which three are reserved for special cases, one is unused and the remainingtwenty-eight are the test points. These test points are numbered TP3 through TP30.

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MATERIAL

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DOVER NtS(AIKII mereUNIVERSITY II Ham EC-I2699 5412442

To describe the operation of the "probe position" detector, first assume that the red probe is inserted

into a TP. A negative going pulse is present at each TP each time the countr is a*. its respective number.

This pulse is fed to U 4A-1 and U20A-1. U14 is a retriggerable one-shot which is 'ield in the ON state bythe recurrence of the pulse at pin I. U20 Inverts the probe pulse which is then gated at U18A with theQ output of Ul4A, This signal is gated again at U18D with a delayed strobepulse from U23B-5 which wasoriginated by the clock input to the counter. This delay insures that the latching strobe occurs during thequiescent state of the counter. The current cmmt held by the counter is then latched into the Dual 4 bit

latch U6. Only five of the eight bits are required to hold the position number. The other three bit positions

are unused.

This action is repeated at an approximate 300 Hz rate as long as the probe is contacting one of the

twenty-eight test points. The latch is always holding the TP number that corresponds with the test pointbeing probed. The output of the latch is fed to one set of inputs of the multiplexer which will be discussed

later.

The previous description is identical for the black probe. The same oscillator, counters and decoders

are used. The gates. one-shot, and latch are repeated as required,

As mentioned earlier, three position numbers are reserved for special cases. The special cases assigned

these numbers are as follows:

0 = Probe open circuited.

1 = Probe grounded to chassis.

2 = Probes shorted together, (This is defined as shorted together only and not touching chassisground or any TP.)

The "probe open circuited" condition is similar to the previously described action except that now

the pulse at U14A-1 is missing and the one-shot reverts to its reset condition. The resultant high level atU18B-5 gates count "0" thrbugh as the strobe to the latch and the latch will contain "0." (Count "0" isalways the strobe to the latches whenever the probes are not in contact with a TP.)

The "probe grounded" and "probes shorted together" cases utilize the voltage comparators Al, A2

and A3 located on the meter board (Figure.3). The diode string consisting of DI through D5 establishes the

reference voltages for the comparators and probes.

Originally when the red probe is open or contacting a test point, its DC potential is held at approxi-

mately +3V through R19. The inverting input of A2 is connected to the red probe through R21. Theuoninverting input of A2 is held at approximately +1.5V through R22. The output of A2 is then at ground

and the gate at U2I B-4 (Figure 4) is held off. The inverting input of A2 will rise to the average DC potential

of the probe and the output will remain at ground. -

It' the red probe is grounded to the chassis, its DC potential, goes to 0 volts and the A2 voltage

comparator output switches to +5V. This enables the gate U21B, allowing the "0" count to be latched as a"one" through the negative output or (NOR) gate U16C.

The black probe operates in the same manner. The inverting input of voltage comparator A3 is held at

+5V through R23 and the resultant switching of the comparator output enables the gate U2 IC, allowing

the black "0" to be latched as a "one."

The last special case is when the probes are shorted together as would be done for zeroing the meter

prior to a resistance measurement. In this case the voltage comparator Al is used. The inverting input of Al

is held _at approximately +3.75V and the noninverting input at the same +3V level as the red probe. In any

case other than the probes being shorted together the output of Al is at ground and the gate U21A is held

off. When the probes are shorted together. the DC level of the noninverting input rises to approximately+4,25V and the output of Al switches to its high level. This enables the gate U2 IA and allows.the red "0"

to be routed through the NOR gates U16D and U I 7B where it is latched as a "two" in both the red and

black latches.

The strobe pulse whose input is at J5-1 (Figure 4) is generated in the I/0 bus line control system each

time the PDP-I I computer-polls the simulator panel. The polling rate is not synchronous with the oscillator

17II

frequency; therefore the strobe pulse is used,,tp, interrupt the oscillator during the interrogation. Thisinsures that the probe position number cannot change during the transfer of data.

The strobe pulse is also used to trigger the two one-shots of U15. Ul5A triggers on the trailing edgeof the strobe and generates the start conversion pulse for the A/D converter U22. The converter will bediscussed later. Ul 5B is a retriggerable one-shot whose Q output switches high and stays high as long as thecomputer is polling the simukitor panel at approximately a 30 Hz or faster rate. This output drivei L3, theON LINE indicator, on the sub-panel to tell the student that the computer is monitoring the panel andproviding a valid meter deflection.

The multiplexer is comprised of six Fairci,ild 9309 Dual Four-input Multiplexer integrated circuits.This couriguiation allows for four words of data transfer to the computer. Each word has a maximum oftwelve b0s, although in the present system only three words of from eight to eleven bits are used. The wordbeieg read is selected by the computer through the two select inputs SO and SI. Table I shows the contents

Table I. Data Words

DATA WORD FROM PDPII . DATA WORDS TO PDP 1 1

So S So S 1 So SI

DATA BIT

NO.

L L

PROBE LOC.

H L

OHMS ADJ.

,POTENTIOMETER

L H

SWITCH POS.

METER MS84

15

14

------MSB

1

FUNCTION SW.4

.. SW.2

13 RED PROBE 16 11 SW. 1

12 RED PROBE 8 _RANGE SW..4

II RED PROBE 4 " SW 2

10 RED PROBE 2 I. SW.1

19 RED PROBE I SCHEM. B11 *8

LS8 8 BLK PROBE 16 LS B sl *4

So 7 BLK PROBE 8 n l * 2S 1 6 BLK PROBE 4 sl el # 1

SIMpLATED"PWR . qWITCHDS I 5 BLK PROBE 2

DS 2 4 8 LK PROBE IID 3 3 I D3 103 Ib3

I D2 2 ID2 102 ID2

ID 1 1 ID I ID I ID I

I DO 0 I DO I DO I DO

18

and bit position of the data for each word. The left-h:ind column of Table 1 is the data word transmitted to

the panel by the computer. The four LSB positions are reserved for the I/0 card LD. number. Data bits4 and 5 control the status of DS2 and DS1, respectively. Data bits 6 and 7 are the word select bits used bythe computer when inputting data. Bits 8 through 15 are the eight bits transmitted to the FM1-8BIN-V D/Aconverter to control Me simulated PSM-6 meter deflection.

Two T1L-308 seven segment displays are wired to the multiplexer output. These displays indicate the

probe positions at all times when SO and SI are low. They are included for maintenance purposes only. Theseven-segment code is semi hexa-decimal and the decimal point is wired to indicate a binary 16. The panelwill operate properly without these indicators installed if desired.

Simulated PSM-6

The simulated PSM-6 consists of the front panel of a real PSM-6 multimeter with all of the electrOnic

circuitry replaced.

The function and range switches are three pole, seven position switches which only encode the switchpositions. The output of the switches are wired to the multiplexer for transfer to the computer.

The ohm zero potentiometer provides a DC voltage between 0 and 5 volts to the FMI158 eight bitA/D converter located on the logic board. The output of this converter is routed to one of the inputs of the

multiplexer. The start conversion pulse, as previously discussed, occurs at the trailing edge of the strobepulse. This allows the setting of the potention:ter to be read into the computer first and then start thecycle for the next conversion. The time required for the conversion cycle is 50 eusec. Reading the previous

result first and then initiating a new conversion cycle provides the necessary time for conversion.

The meter movement is the original PSM-6 50p ampmeter. The meter protection diode zssembly(E101) was retained from the original component board. R6 is used to adjust the meter deflection to full

scale during calibration.

The deflection voltage is provided by the D/A converter located on the 1/0 interface card in the card

nest assembly (Figure 5). The converter is wired for bipolar operation so that a reversed meter deflection

can be simulateti The inverters and gates at U1-U4 are used to modify the digital input from the computerbefore it enters the converter. This insures that the meter cannot be overdriven in the reverse directiun.

Table 2 illustrates how this conversion is used.

Table 2 _Binary Conversion

Binary fromComputer

BinarY into Meter ReadingCi/A Converter (0-100 Seale)

I XX XXX00* 01111100 3.300000000 10000000 0

00111100 10111100 +50

01111000 11111000 +100

01111111 11111111 +105.8

*X = Don't care

Any time the binary number from the computer contains a "1" in the most significant bit (MSB)position the D/A converter output will be V. The "1" in the MSB position is inverted at Ul A and appearsas a "1" at five of the other seven binary inputs to the converter and limits the negative excursion of the

meter to 33 divisions. This is enough to show a reversed meter probe condition but not enough todamage the meter movement. The largest binary number into the converter produces a deflection of about

106 divisions which will show an out-of-range setting of the range switch.but again, not enough to damage

the meter. The meter deflection is calibrated by first adjusting RI (Figure 5) for a zero meter reading whenthe computer is sending a binary zero to the 1/0 interface card and then adjusting R6 on the meter board(Figure 3) for full-scale deflection when the binary number 01111000 is being transmitted.

13

1 9

2 0

A c 0

I/0 INTERFACE I:14

OW II

OUT

OUT

OUT 8

OUT 7

OUT 6

OUTS

OUT 4

OUT 3 (Iurr 2

IT I01.1 0 (

1198IN u>

IN 10

IN 9

03

IN 8)

IN 7)

IN 6

U10

740405

21

1404Ns

IN 3)

IN 2)

IN I>

IN 0>

1,130

7400le

u44 3

,400

6451400

NB

Figure 5, Meter DA

FRON MOO

ME T CH

JO 1

J2

a 5J2 4

.11 5

-(J2 6IJ2

(J2 842 9

10J2

JO II

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4111

411-551Nit

11

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NETER ZERO ADJUST

02

6046n

J1.5 TO

1,16

CHI

Z0--...0.I5V

10.45Y

JI 3 yi

JI4 2 So

SJ1 II

J1 10 1.2

JI

4J1

OR 1/0 INTERFACE CARD

=1.

--r

JI

....wrommino. lITJmaws 1.1.=Mk MEM.reAml 1/111441

9ETER

EMEMLII00(411 =ARCH NV=

UNIVERSITY II DOM EC-I2700

Meter Board

The remaining circuits shown on the meter board (Figure 3) that have not been previously discussed

ale the lamp drivers and switches S3 thniugh S7. Q I and Q2 drive the indicating 14:Ds DS1 and DS2 upon

command by the computer through the 1/0 interface card. Q3 drives the ON LINE indicator by the actionof the retriggerable one-shot multivibrator that was discussed in the logic board section.

.S3 through SO ale pushbutton switches mounted behind the sub.panel so that the pushbuttonsprotrude thrOugh the panel. These switches are actuated by the schematic board installed in the operatingposition on the panel. The milled depressions on the back side uf each schematic board encode it with itsunique identification number. Up to fifteen different schematic boards can be encoded.with the four bitcode provided..The binary mitnlvr fifteen is reserved to indicate to the cotnpater that no board isinstalled

on the panel.

S7 is the simulated POWER switch. This switch is the physical counterpart of the switch labeled SI

on each of the schematic boards. Its only operation is to indicate tu the computer if the student has turned

the power ON or OFF before taking voltage or ohmmeter readings.

III. MMNTENANCE

Only two adjustments are required itt the alignment of the system. The procedure for these adjust-

ments are as follows:

1. Use the PDP-1 I ODT program to transmit the data word 000001 to address 767742.

2. Adjust RI on the "users portion" of the I/0 interface card for a zero reading on the simulatedPSM-6 meter.

3. Transmit the data word 074001 to addr%;ss 767742 and adjust R6 on the meter board for fullscale deflection of the meter.

Linear and digital integrated circuits are used'almost exclusively throughout the system and replace-

ment is required if a inalfunction occurs. Most of the Ws are n:ounted in sockets and replacement is easily

accomplished. A number of discrete'components on the meter board are soldered tu the eyeleted board.Good soldering techniques. and the use of appropriate soldering and unsoldering aids, will insure trouble-

free replacement.

The +5V powci supply is located in the 1/0 bus line card nest and is adjustable. The adjustmentpotentiometer is located on the supply printed circuit board. This adjustment should not be attemptedwithout a calibrated digital voltmeter. The +I5V supply is a sealed unit and must be replaced if found

defect ive.

REFERENCES

Wasmundt, K.C., & Steffen. D.A. Software jiir perfornuince training carrel. AH-1RL-TR-76-62 (II). LowryAFB, CO: Technical Training Divisirm. Air Force Iltiman Resources Laboratory'. September 1976:

West, A.S., Wasimindt. K.C.. Latttz, A.E.. Steffen, D.A.. & Miller, G.G. Performance training carrel evalu-ation. AFHRL-TR-76-62 (111). Lowry AFB. CO: Technical Training Division, Air Force Human

Resources Laboratory. in press.

*U S. GOVERNMENT PRINTING OFFICE:1977- .771_057/3u

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