JCE Software, 4D2: PSL Photometer

PSL Photometer

Steven D. Gammon
University of Idaho, Moscow, ID 83844

Note:
This program is out of print.

The majority of freshman chemistry laboratory programs include experiments that employ visible spectroscopy to teach Beer's law and derive related concentration information. These experiments are often done with a Baush & Lomb Spectronic 20 or Spectronic 21. While these experiments and equipment are "status quo" at most institutions, they do have a number of limitations. We have developed an alternative instrument and software that offers significant advantages over the above spectrometers.
The instrument is constructed from PVC "Tee" pipe, an LED, and employs the Team Labs Personal Science Lab interface (1) and a Radiometric Light Probe. Construction of the photometer from the PVC pipe is simple and inexpensive. The instrument has demonstrated both adequate sensitivity and selectivity to be an effective replacement for the above spectrometers in an undergraduate teaching laboratory. (2)

The opening screen from PSL Photometer.

In order to drive the instrument, PSL Photometer was developed to run under the Microsoft Windows operating system. In order to allow students to collect valid information without significant intervention by an instructor, a simple, user-friendly interface is employed. PSL Photometer allows students to create a standard calibration curve, take measurements on solutions of unknown concentration, and perform a linear least squares analysis on the calibration data. All the collected data are printable and can be saved as an ASCII file for spreadsheet use or inclusion in a computer generated report. A sample screen from PSL Photometer is shown in Figure 2.
PSL Photometer has many unique features that make it ideally suited to undergraduate teaching laboratories and taking analytical sample measurements in the field. First of all, once launched, the program can detect whether the instrument is present and correctly configured. When printing, the Windows Print Manager handles printing problems. In all instances, if a problem is detected, feedback and suggestions to correct the problem are provided. There is also extensive on-line help that is fully searchable, has all the features common to most commercial Windows applications, and is available at any time. Help also contains content information on how calibration works and the configuration of the measurement hardware. All of these feedback mechanisms create an environment that ensures that students will be able to collect valid data.
Another important feature of PSL Photometer is that the instructor has the flexibility to configure the "instrument" software for his or her teaching situation. Through the "Configure Instrument" option, the instructor may enable or disable: printing, linear regression analysis of the calibration data, displaying the graph of the calibration data, and/or calculation of the unknown concentration(s). If all the configurable features are turned "off", one has the minimal instrument that behaves like the Spectronic 20. This may be desirable if the instructor feels the students need experience in graphing and linear regression. With the features turned "on" one has an instrument that provides all the possible information that can be obtained from a colorimeter. Finally, a custom configuration can be chosen with just the features that meet instructional goals. To prevent the students from changing the configuration of the instrument, this option is only accessible through a password.
Hardware and Software Requirements
PSL Photometer requires Microsoft Windows version 3.1 or later and a compatible computer. We recommend an IBM-PC or compatible with a 80386 or higher processor, a minimum of 4 MB of memory, a hard disk, one floppy disk drive to install the software, a mouse, and a Windows-compatible graphics card, such as an IBM VGA or Super VGA adapter with a compatible color monitor. DOS 5.0 or later is highly recommended.
PSL Photometer also requires Team Labs Personal Science Lab (1) equipment with radiometric light probe and a PVC photometer (2).
Literature Cited

The product formerly called the IBM Personal Science Lab (PSL) is now the Team Labs PSL (Team Labs, 6390B Gunpark Dr. Boulder, CO 80301).
Pharr, C. M., Malmberg, B. J., Jegla, J. D., and Gammon, S. D., J. Chem. Educ., 1996, 73 (3) 238-243.

First Published: February 1997
Citation: Gammon, S. D. . PSL Photometer J. Chem. Educ. Software 4D2
Keywords: Computer Room; Laboratory; High School; General; Lab interface--PSL; Visible spectrophotometry

News | Issues | CD-ROM / Video | Find It! | Technical Support | For Authors

JCE Online | Journal | Software | Internet | Happenings | About JCE | Contact JCE

Last Updated: April 26, 2001
Created: December 9, 1996 Created by: S. B. Mathews
Comments to: jceonline@chem.wisc.edu

© 1997 Division of Chemical Education, Inc., American Chemical Society. All rights reserved.



PSL Photometer
Steven D. Gammon University of Idaho, Moscow, ID 83844

Note:	This program is out of print.

The majority of freshman chemistry laboratory programs include experiments that employ visible spectroscopy to teach Beer's law and derive related concentration information. These experiments are often done with a Baush & Lomb Spectronic 20 or Spectronic 21. While these experiments and equipment are "status quo" at most institutions, they do have a number of limitations. We have developed an alternative instrument and software that offers significant advantages over the above spectrometers. The instrument is constructed from PVC "Tee" pipe, an LED, and employs the Team Labs Personal Science Lab interface (1) and a Radiometric Light Probe. Construction of the photometer from the PVC pipe is simple and inexpensive. The instrument has demonstrated both adequate sensitivity and selectivity to be an effective replacement for the above spectrometers in an undergraduate teaching laboratory. (2) The opening screen from PSL Photometer. In order to drive the instrument, PSL Photometer was developed to run under the Microsoft Windows operating system. In order to allow students to collect valid information without significant intervention by an instructor, a simple, user-friendly interface is employed. PSL Photometer allows students to create a standard calibration curve, take measurements on solutions of unknown concentration, and perform a linear least squares analysis on the calibration data. All the collected data are printable and can be saved as an ASCII file for spreadsheet use or inclusion in a computer generated report. A sample screen from PSL Photometer is shown in Figure 2. PSL Photometer has many unique features that make it ideally suited to undergraduate teaching laboratories and taking analytical sample measurements in the field. First of all, once launched, the program can detect whether the instrument is present and correctly configured. When printing, the Windows Print Manager handles printing problems. In all instances, if a problem is detected, feedback and suggestions to correct the problem are provided. There is also extensive on-line help that is fully searchable, has all the features common to most commercial Windows applications, and is available at any time. Help also contains content information on how calibration works and the configuration of the measurement hardware. All of these feedback mechanisms create an environment that ensures that students will be able to collect valid data. Another important feature of PSL Photometer is that the instructor has the flexibility to configure the "instrument" software for his or her teaching situation. Through the "Configure Instrument" option, the instructor may enable or disable: printing, linear regression analysis of the calibration data, displaying the graph of the calibration data, and/or calculation of the unknown concentration(s). If all the configurable features are turned "off", one has the minimal instrument that behaves like the Spectronic 20. This may be desirable if the instructor feels the students need experience in graphing and linear regression. With the features turned "on" one has an instrument that provides all the possible information that can be obtained from a colorimeter. Finally, a custom configuration can be chosen with just the features that meet instructional goals. To prevent the students from changing the configuration of the instrument, this option is only accessible through a password. Hardware and Software Requirements PSL Photometer requires Microsoft Windows version 3.1 or later and a compatible computer. We recommend an IBM-PC or compatible with a 80386 or higher processor, a minimum of 4 MB of memory, a hard disk, one floppy disk drive to install the software, a mouse, and a Windows-compatible graphics card, such as an IBM VGA or Super VGA adapter with a compatible color monitor. DOS 5.0 or later is highly recommended. PSL Photometer also requires Team Labs Personal Science Lab (1) equipment with radiometric light probe and a PVC photometer (2). Literature Cited The product formerly called the IBM Personal Science Lab (PSL) is now the Team Labs PSL (Team Labs, 6390B Gunpark Dr. Boulder, CO 80301). Pharr, C. M., Malmberg, B. J., Jegla, J. D., and Gammon, S. D., J. Chem. Educ., 1996, 73 (3) 238-243.


News \| Issues \| CD-ROM / Video \| Find It! \| Technical Support \| For Authors
JCE Online \| Journal \| Software \| Internet \| Happenings \| About JCE \| Contact JCE

Last Updated: April 26, 2001 Created: December 9, 1996	Created by: S. B. Mathews Comments to: jceonline@chem.wisc.edu

© 1997 Division of Chemical Education, Inc., American Chemical Society. All rights reserved.