Instruction Sheetfor the PASCOModel WA-9613012-03479C4/95$1.00Phone (916) 786-3800 • FAX (916) 786-8905 • email: [email protected] Foothills Blvd. • P.O. Box 619011 • Roseville, CA 95678-9011 USAbetterteach physicsways to© 1990 PASCO scientificThis instruction sheet written/edited by: Dave GriffithDriver/Detector Coils(for use with the WA-9611 Sonometer)IntroductionThe PASCO Model WA-9613 Driver/Detector Coils aredesigned to be used with PASCO’s Model WA-9611Sonometer. The Driver Coil, when powered by a functiongenerator (such as PASCO Models PI-9598 StudentFunction Generator or PI-9587B Digital Function Gen-erator) capable of delivering up to 0.5 ampere, inducesvibrations in the steel wires of the Sonometer. The ampli-tude and frequency of the vibrations are determined bythe output of the function generator. The Detector Coilconverts the wire vibrations into an electronic signal thatcan be viewed on an oscilloscope, producing a trace thatshows the motion of the wire at the position of the Detec-tor Coil.You can use a PASCO Computer Interface such as theCI-6500 for DOS-compatible computers or the AI-6501for Apple® II computers in place of the oscilloscope.You can use a PASCO Computer Interface such as theCI-6550 for Macintosh® computers or the CI-6565 forWindows™-compatible computers with a PASCO PowerAmplifier in place of both the oscilloscope and the func-tion generator.WA-9613PASCO scientificDRIVERWA-9613PASCO scientificDETECTORBNC adapterEquipmentThe Driver/Detector Coils come with a BNC adapter.You can use the BNC adapter and a CI-6503 VoltageSensor to connect the Detector Coil to the CI-6550 or CI-6565 Computer Interface.Additional Equipment• WA-9611 SonometerRecommended Equipment• CI-6550 or CI-6565 Computer Interface and aPower Amplifier (CI-6552)OR• Series 6500 Computer Interface, CI-6508 InputAdapter Box, and a function generator capable ofproducing 0.5 AOR• dual trace oscilloscope and a function generatorcapable of producing 0.5 AOptional Equipment (for use with function generator)• banana plug patch cords and BNC-to-dual bananaadapter (for connecting the function generator tothe BNC connector on an oscilloscope)2Driver/Detector Coils 012-03479CWA-9611SONOMETERKEEP WEIGHTS AS NEAR TO FLOORAS POSSIBLE IN THE EVENT THESONOMETER WIRE SHOULD BREAKCAUTION!1.75 kg MAXIMUMLOAD ON LEVERBK PRECISION200 Mhz OSCILLISCOPEMODEL2120INTENSITY FOCUSTRACE NOT ATIONTRIG LEVELCOUPLE SOURCESLOPE - YTIME/DIVX-POSVAR VARVAR SWEEPCALCALmVVCH 1VOLTZ/DIVCH 2VOLTZ/DIVCALmVVVERTICAL MODEPULL XS PULL XSCH 2 ∞CH 1 ∞ACDCACDCAC CH1CH2ALTEXTPOS POSNORMEXTCH1CH2NORMEXTCH1CH2MANUAL AUTOT X-YT X-YLINECAL EXT CH4POWER200VMAX400VMAX400VMAX-++-TTLHIΩGNDLOΩMINRANGEADJUSTMAXOUTPUTFREQUENCYAMPLITUDEPI-9587BDIGITAL FUNCTIONGENERA TOR -AMPLIFIERHERTZWAVEFORMINPUTGNDEXTERNALDETECTORW A-9613DRIVERWA-9613OperationTo connect the Driver/Detector Coils to a functiongenerator and oscilloscope:➀ Connect the Driver and Detector Coils to the functiongenerator and oscilloscope as shown in the diagram.Connect the Driver Coil directly to the output of thePASCO PI-9587B Digital Function Generator. Connectthe Detector Coil directly to channel two of an oscillo-scope that has a BNC connector. You can use bananaplug patch cords and a BNC-to-banana plug adapter toconnect the output of the function generator to channelone of an oscilloscope that has a BNC connector.➁ Set the gain on channel-one of the oscilloscope to 5mV/div. Adjust the oscilloscope so it triggers on thesignal from the function generator.➂ Position the Driver Coil approximately 5 cm from oneof the bridges of the Sonometer.Depending on the wave pattern you are trying to pro-duce, you might want to place the driver at some otherposition. It will drive the string best if it is placed at anantinode of the wave pattern.➃ Position the Detector midway between the bridges ini-tially, though for some patterns, you may want to re-position it to best pick up the signal. As with theDriver Coil, it works best when positioned near an an-tinode of the wave pattern.➄ Set the function generator to produce a sine wave. Setthe frequency to a value between 100 and 200 Hz. Ad-just the amplitude to about 5 V (approximately half ofmaximum). Slowly vary the frequency of the functiongenerator output. When you reach a resonant fre-quency, you should see the motion of the string andthe sound produced by the vibrating string should be amaximum. The wave pattern shown on the oscillo-scope should become a clean sine wave. If you can’tsee or hear the string, raise the amplitude of the func-tion generator output and try again.Using the Driver/Detector Coils with a PASCOComputer InterfaceThere are several ways to use the Driver/Detector Coils witha PASCO Computer Interface. The method you use dependson the kind of computer, the interface (e.g., CI-6500, CI-6550,etc.), the device to control the driver coil, and whether youwish to do frequency analysis (Fast Fourier Transform orFFT) of the standing waves produced by the driver coil.Computer Interface Device to drive coil Software FFT?Apple II AI-6501 Power Amplifier Power Amplifier (Apple II) noApple II AI-6501 function generator Data Monitor (Apple II) noDOS - PC CI-6500 Power Amplifier Power Amplifier (MS-DOS) noDOS - PC CI-6500 function generator Data Monitor (MS-DOS) yesMacintosh CI-6550 Power Amplifier Science Workshop (Mac) yesMacintosh CI-6550 function generator Science Workshop (Mac) yesWindows - PC CI-6565 Power Amplifier Science Workshop (Windows) yesWindows - PC CI-6565 function generator Science Workshop (Windows) yesWindows - PC CI-6500 function generator Data Monitor (Windows) yesFunction GeneratorOscilloscopeDriver CoilDetector coilChannel 2Channel 1 (trigger)3012-03479C Driver/Detector CoilsTo connect the Driver/Detector Coils to a PowerAmplifier and PASCO Computer Interface:• Connect the Power Amplifier DIN plug to channelC of the interface. Connect the Driver Coil to theoutput of the Power Amplifier.➤ CAUTION: Do not turn on the power amplifieruntil you have set the output amplitude from withinthe program.For the Series 6500 Computer Interface (e.g., CI-6500):• Connect the BNC plug on the Detector Coil to theBNC jack on the CI-6508 Input Adapter Box, andthe DIN plug on the Adapter Box to channel A ofthe interface. Turn the amplification select switchon the CI-6508 to 100X.For the CI-6550 or CI-6565 Computer Interface• Connect the BNC plug on the Detector