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Op Amp Challenge Manual

PROGRAM PURPOSE

 

Op Amp Challenge allows instructors to add computer-based instruction to their operational amplifier training without changing textbooks or classroom instructional methods. Op Amp Challenge is not intended to replace textbooks and classroom instruction. The program is designed to supplement other instructional methods by providing rich and varied activities with rapid feedback. All learner responses are evaluated immediately. Learners are shown the response after an incorrect response has been entered.

 

LEARNING

 

Students can use the program to practice a procedure until a topic is mastered. New variables are selected each time an activity is used. Students cannot simply memorize the answers. In addition, the order of the items is changed each time an activity is used. There should be little concern with grades in the early stages of learning a topic. Once the topic is understood, then students can set an objective of improving both the score and time on each activity. Many students thrive in environments that allow self-pacing and discovery.

 

TESTING

 

The activities within Op Amp Challenge can be used for testing when used in a supervised setting. The program produces an optional “Certificate” printout that can be used to report scores. In addition, scores can be stored on disk drives or diskettes. Students being tested simultaneously cannot cheat because the order of activity items and variables will be different for each student.

 

LABORATORY

 

Two activities are included that can be used to facilitate laboratory activities. The Active Filter Calculator and RC Oscillator Calculator activities can be used by students to design circuits to the instructor's specifications.

 

Op Amp Challenge is a nonlinear learning program. Students can begin anywhere and stop anywhere. The program does not dictate the order or pattern of learning. Any activity can be chosen from the main menu by clicking on the appropriate button. The topic button takes the student to the introduction page for the activity.

 

 

PROGRAM STRUCTURE

 

 

INTRODUCTION PAGE

 

The introduction page describes the activity in general terms. Most introduction pages will have several tabs that can be selected to give additional details, examples, and circuit diagrams. The introduction information can be studied at any level of detail the student chooses. A click on the “Begin” button takes the student to the activity page.

 

ACTIVITY

 

Each activity has a short explanation at the top of the activity page. Items are presented one at a time for the student to accomplish. Student's answers are typed into a space provided on the page. The student must click on “Grade Answer” to have the program evaluate the answer provided. The word “CORRECT” in red appears above the student's answer if the answer is correct. The correct solution appears in gray above the student's answer if the answer is incorrect. The student clicks on the “Continue” button when ready to go to the next item.

 

GRADE

 

A grade is awarded after all items of an activity have been finished. The student will then be offered the option to print a grade certificate or store the score on a diskette. The program returns to the main page of the program after each activity.

 

Some of the troubleshooting activities do not have percent scores.  Students earn a score between 0 and 150 points on the advanced troubleshooting activities. The score indicates student ability to identify circuit faults efficiently.

 

There are no grades awarded on the “Calculator” activities.

 

 

GRADE RECORDING

 

At the conclusion of each activity the program will request the student's name and ID code. The name field must contain characters a through z and spaces only. Punctuation and numerals cannot be entered in the name field. The ID code can be assigned in any manner so long as it consists of all numeric digits and has between two and nine digits. The ID code is used to construct a name for the file containing a student's grades. A teacher could assign an ID code of 2201 as the ID code to be used by students in second period math section 201 for example. The ID code merely establishes a name for a disk file. The ID Code has no significance if grades are not stored on diskettes. After the name and ID code have been entered, the student selects one of two buttons, “STORE GRADE ON DISK” or “SKIP GRADE DISK STORAGE”. A diskette must be in the disk drive prior to selecting “STORE GRADE ON DISK”. The program then gives the student the option of printing or not printing a certificate.

 

The disk score storage feature can be set to store grades on disk drives other than diskettes. Click on the “Program Options” tab for details on disk storage setup.

 

Grades printed on certificates and stored on diskettes include the topic title, student name, ID code, date, time, time on task and validity code. The validity code is an encrypted signature that can be used to determine if modifications to the certificate or file record have been made.  A validity checking utility is included on the opening page of this program. A utility is also included for printing student's grades stored on diskettes.

 

 

REQUIRED ACCURACY

 

This program grades numeric answers to a percentage of accuracy. Any answer that is within plus or minus one percent of the right answer is counted as correct. In general, answers that are correct to at least three significant digits will be well within the accuracy required. A number with three significant digits is accurate to about one part in a thousand or 0.1%. Do not confuse significant digits with digits after the decimal. These are two different measures of accuracy. Significant digits are the correct digits not including placeholder zeros. The number 30.46 has four significant digits. Zeros included between nonzero digits are significant. The number 0.00073 has only two significant digits. Leading zeros are not significant. Additional information on accuracy and significant digits can be found in many math textbooks.

 

The examples and correct answers in this program are calculated to six significant figures of accuracy in most cases. The numbers displayed may be truncated to fit the area available for display. This may cause you to obtain a slightly different result in the fifth or sixth digit when you work through the problem on a calculator.

 

USING THE WINDOWS CALCULATOR

 

The Window's calculator can be used with this program. The easiest way to use the Window's calculator is to start the calculator program from its icon. Then reduce the calculator to an icon on the toolbar by clicking the minimize button, (The _ button at the upper right of the calculator).  Start the Op Amp Challenge program by clicking its icon. The calculator can be used at any time now by pressing the Windows button, (the button with the Windows symbol at the lower left corner of the keyboard). The tool bar will appear at the bottom of the screen. Click on the calculator button to pop the calculator up for use. The calculator can be dismissed by either clicking the calculator minimize button or clicking outside of the calculator.

 

A calculated number can be pasted directly into an Op Amp Challenge activity by following the steps listed below.

 

Click on Copy in the Edit menu on the calculator. You can also type Ctrl/c, (Type c while holding down the Ctrl key).

Click on the answer block of an Op Amp Challenge activity. Type Ctrl/v, (Type v while holding down the Ctrl key). Most operating systems will also allow pasting by clicking the right button while the mouse pointer is on the answer block. A menu will appear in which the user clicks on the paste option.

 

Pasting numbers with many digits will cause only the last digits to be visible in the answer edit block. You can use your mouse or cursor keys to scroll left to view all of the pasted digits.

 

ADVANCED FEATURES

 

ADVANCED FEATURES

 

This document supplies information useful for setting up the diskette score storage feature. Other program options are also described. It is recommended that instructors experiment thoroughly with the diskette grade storage feature before applying its use with students. The student ID can be carefully designed to help identify grades from particular classes and students.

 

SCORE STORAGE

 

Student scores can be stored on a diskette. A diskette must be in the drive prior to choosing this option. Errors and possible loss of the score data may occur if the drive does not contain a diskette. The file generated by the disk storage feature is given a DOS compatible file name, gxxxxxxx.xx, where the lower case "g" is always the first letter in the file name. The xxx... is the student ID that is a sequence of two to nine numeric digits. The file is a simple ASCII text file that can be read and examined with any word processor. Do not examine and resave a student grade file under the original name with a word processor! This can make the file appear corrupted by the score printout utility. Word processors inject formatting characters into a file. This program calculates and stores a code with each record in the student score file. This Validity Code is a simple encryption signature designed to reduce the possibility of file entry alteration and the generation of duplicate records. The Validity Code provides some low-level security but is certainly not hack proof. The validity of records can most easily be checked by use of the "Print Grade File" option.  This option produces a formatted printout of a selected student grade file. Never attempt to use this option to print any other file type. Each grade record in the file is validity checked. An "E!" is printed after all records failing the validity test. The routine also checks for duplicate records that are indicated by "D!" printed after the duplicate record.

 

This program stores student grade files on diskette drive A: by default. One may want to store grade files on another drive or directory under some circumstances. See the next paragraph for instructions on changing the path for student grade files. The student records will be stored in a file named gxxxxxxx.x where the x(s) represent the digits of the student's ID Code. The ID Codes are a series of numeric digits. The ID Code must be at least 2 digits long but no longer than 9 digits. A DOS filename is generated with an appended lower case g followed by up to 7 digits. Any additional digits are added after a period to produce a legal DOS file name. The file is a simple ASCII text file that can be viewed with any word processor. The score printing options in this program can detect modifications to the file. In addition, individual records in the file can be validity checked by use of a procedure in this program. These validity-checking procedures are not intended to offer high data security.

 

INITIAL OPTIONS

 

This program reads the file "options.ini" on each startup. The file options.ini is located in the same directory as the program file. The first entry sets the condition for the certificate printing option default condition. The two possible settings are:

 

CERTIFICATES ON or CERTIFICATES OFF

 

The second entry in the “options.ini" file sets the default condition of the disk storage feature for grades. The two possible settings are:

 

DISK STORAGE ON or DISK STORAGE OFF

 

The third entry in the “options.ini" file sets the default condition of the wallpaper option. The possible settings are:

 

WALL PAPER ON or WALL PAPER OFF

 

All characters in the above initialization options must be in upper case characters. All characters are significant including spaces. Any error in spelling, spaces, or case will cause the option to default to the ON setting.

 

Line 4 of the option.ini file contains the path for student grade file storage. Errors in formatting this line may cause program execution errors. Any directory or subdirectory paths given must exist prior to program execution. The program will not create directories. No entry on line 4 will cause the program to default to a:\ as the path for student grade storage. A few examples of paths and explanations are given below.

 

b:\

 

The student grades will be stored on drive b:

 

c:\stuff\

 

The student grade files will be stored in the "stuff" directory of c: drive. Caution! You must create the "stuff" directory prior to running the program.

 

c:\records\student\

 

Grade files will be stored in the "student" subdirectory of the "records" directory of c: drive. Again, you must create the directory structure prior to running the program.

 

Additional program options are documented in the file OPTIONS.INI. This file is located in the install directory of the program. Caution should be observed in making changes to the OPTIONS.INI file. Errors in some entries can cause non-recoverable faults. Additional options include hiding utility buttons and hiding the grader (graphic) on certain activities.

 

The OPTIONS.INI file has additional internal documentation. Use a plain text editor to view or print the file. The OPTIONS.INI file must not be saved in a word processor format. The program must always be saved in plain DOS text format.

 

DISKETTES

 

Floppy disk data is easily corrupted or destroyed in several ways. Students should be strongly advised to make backup copies of their floppy disk grade files frequently to avoid data loss problems. Teachers can prevent massive data losses by processing student floppy disk files often.  This also encourages students to have assignments completed on time.

 

VIDEO DISPLAY

 

This program should run on any Windows Vista, XP, 98 or Me platform. The evaluation version of the program should be tested on target machines prior to licensing the program. The best display is obtained with a 16-bit or 24-bit color setting and resolution set to 600x800 or higher. There will be some distortion caused by palette flash when used with video set to 256 colors. Where resolutions above 600x800 are used, the working window is centered with the unused area wallpapered by default with the image chips.bmp found in the install directory. This program requires at least 256 colors to function.

 

WALLPAPER

 

The file chips.bmp can be deleted or renamed to allow normal task switching as no wallpaper will be displayed. This can be useful to more advanced students who are familiar with task switching.  The wallpaper is useful to beginners because accidental task switches are unlikely.  Another bitmap file can be substituted for chips.bmp. The file will be tiled as wallpaper across the unused portion of super VGA displays. Some institutions may want to display school or department logos on the wallpaper.