In This Issue:
The Caliper V14 #1 Cover
Chemistry
Biology
Physics
CBL™ News
Workshops & Contests
Bits & Bytes
Science Humor

New Products:
New Motion Detector
Lower Priced Sensors
Exercise Heart Rate Monitor
Instrumentation Amplifier
Ion Selective Electrodes
Rechargeable Battery Pack
Logger Pro Books
CBR™
TI-86

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The Caliper

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Vernier Home Page

We are very excited about our new Motion Detector. We have greatly improved its ease of use by adding a pivoting head, a clamp, interchangeable cable, and rubber feet. Best of all, the new Motion Detector is the same price as the old one. The new Motion Detector is a joint project of Vernier Software and Texas Instruments. The motion detector is available with any of three different connectors:

While the new motion detector looks like a CBR™ from Texas Instruments, it is not the same thing. See page 8 of this newsletter for information on the CBR.

This sensor allows you to monitor your heart rate while you exercise, run, or jump. We have a number of sample graphs made using the Exercise Heart Rate Monitor (EHR-DIN, $89) on page 5 of this newsletter.

We get many requests from universities and high schools to amplify analog signals from lab instruments up to the voltage range of our lab interfaces. Now we have the Instrumentation Amplifier to monitor voltages from a few millivolts (DC or AC). It has several switch settings to allow you to select the best gain: 0-20 mV, 0-200 mV, 0-1 V, ±20 mV, ±200 mV, and ±1 V. It can be used with any of our computer lab interfaces, as well as the Texas Instruments CBL. Typical uses would include:

• amplifying the chart recorder output of any instrument (such as a Gas Chromatograph) so that its signal can be used with our lab interface.
• building a current (amperage) probe by measuring the voltage drop across a resistor.

Gillian Gardner of the Lewis and Clark College, Portland, OR, Chemistry Department let us connect the Instrumentation Amplifier to a GOW-Mac Series 350 Gas Chromatograph to collect data using a sample of fatty acids dissolved in toluene solvent. The data were collected using our Serial Box Interface. Following the initial solvent peak, the five fatty acid peaks are identified, and their respective integrals calculated using our Logger Pro software.

We have worked this year to reduce the price of data collection hardware. As a result, we have three new and improved probes with lower prices than the ones they replaced:

Vernier Photogate (VPG-DG): This is the least expensive, assembled photogate ever sold. It comes with a mounting rod for connection to a ring stand. An optional pulley (SPA) can be added to use it as a Smart Pulley.

Student Radiation Monitor (SRM-DG, $138): We left the display off this radiation sensor to lower the cost. It also features improved beta and gamma sensitivity.

Dual-Range Force Sensor (DFS-DIN, $98): This is our best force sensor yet. It has two ranges: ±5 N and ±50 N. It is easy to hold in your hand, but it also comes with a bracket, which makes it easy to mount on a PASCO cart.

We are pleased to announce that a new family of ion-selective electrodes will be available in our 1998 catalog (shipping after February 1, 1998). The initial species available will include four electrodes: Nitrate (NO3 - ), Chloride (Cl - ), Calcium (Ca 2+ ), and Ammonium (NH4 + ). We chose these four ions because of their importance in environmental monitoring. We get many requests for nitrate testing in water quality studies. Calcium is very useful as an indicator of hardness of water. Chloride is a good indicator of water salinity, and ammonium is often present as a result of fertilizer in water runoff from fields. These easy-to-use electrodes will be priced at under $150. An Ion-Selective Electrode Amplifier will be priced at under $45—one ISE Amplifier can be purchased for use with multiple electrodes. Here are some features of our ISEs:

• Electrodes are stored dry, and have either solid state or PVC membranes.
• Vernier ISEs are a combination-style, non-refillable, gel-filled construction—no messy filling of ISEs. They are ready to use in a matter of minutes.
• Each electrode has a built-in protective guard.
• Other ion-selective electrodes will be available later in 1998.

We have had a battery holder for the Serial Box Interface for several years. It is handy when you are using your Serial Box Interface with a laptop computer in the field. Our new battery pack (Order Code RBP, $59) contains a set of rechargeable batteries and a complete battery-charging system. When the new battery pack is in the Serial Box Interface, all you have to do is plug in the AC power supply and the batteries will be recharged.

We have recently revised three of our lab manuals to match the Logger Pro software. The new versions have the following order codes:

Watch for a new book Physics with Computers (PWC-LPW, $35). The authors are Ken Appel, Clarence Bakken, and John Gastineau. We hope to have this book available in our 1998 catalog. It includes labs from many areas of physics and uses a wide variety of sensors. Like all of our “...with Computers” books, it will include disks with experiment files and the word processing files of the student handouts so that you can edit the labs.

If you teach math, physical science or physics, and don’t have a CBL, you may want to consider the new CBR— the least expensive and easiest way to collect motion data in your classroom (order code CBR, $95). The CBR is unique because it collects distance, velocity, and acceleration data while connected directly to a TI graphing calculator, so you don’t need the CBL. Equally important is that the CBR contains built-in programs. You send programs directly from the CBR to the calculator, so you don’t need a TI-GRAPH LINK. Other important features include the following:

• The CBR is built with a pivoting head, making it easy to set up experiments.
• It comes with a versatile, detachable clamp.
• A manual trigger button lets you collect data on demand or while detached from the calculator.
• Students can repeat data collection quickly by pressing just one button.
• It works with TI-82, TI-83, TI-85, TI-86, and TI-92 calculators.
• The CBR can also be connected to a CBL (extra cable required).
• The built-in program supports popular activities, such as Distance Match

The newest addition to the line of CBL-compatible calculators is the TI-86. This calculator has all the functions of a TI-85, but it has been enhanced to make it more versatile and easier to use. Like the TI-85, this calculator was designed primarily for college math, science, and engineering, but it will work well in upper-level high school science and math courses. We like it because it has more than three times the memory of the TI-85. You can store all of our CBL programs on one calculator and have plenty of room to collect data. In addition, data are now displayed in a list editor, like the TI-82 and TI-83. The Trace feature makes it easy to read data directly from a graph.