OCLI Instrumentspubs.acs.org/doi/pdf/10.1021/ac60296a756strumentation systems and compo- nents is rapidly becoming a nec...
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EDITORS' COLUMN AT LEAST a rudimentary under standing of digital and analog in strumentation systems and compo nents is rapidly becoming a neces sity for the practicing analytical chemist. The unwary scientist, tempted by the many new data han dling and digitizing devices avail able today, may incorporate an un wise combination of units into his system and actually degrade the output accuracy! In this month's Instrumentation feature, page 69A, Professor C. G. Enke of Michigan State University introduces a number of "data do mains" concepts which analytical chemists will find most useful in de signing and modifying analog, digi tal, and analog/digital measure ment systems and devices. Profes sor Enke has for a long time been a leader in educating scientists in the intricacies of electronics. His pres ent article provides a means of uti lizing the latest electronic devices, such as digital frequency meters, signal averagers, digital pH meters, "digitized" gas chromatographs and double-beam spectrophotometers, and Fourier transform spectrom eters, efficiently and effectively, with no more knowledge necessary than an understanding of the basic measurement process. In the future we shall feature, as a sequel to Professor Enke's ar ticle, a discussion and review of the analytical aspects of the digitiz ing step in digital instrumentation, authored jointly by Professor Stuart P. Cram of the University of Flor ida and Professor Harry L. Pardue of Purdue University. The quanti tative aspects of digitizing and in strumentation performance and specifications will be considered for this important step prior to data ac quisition or reduction. The similar ities and differences between volt age-to-frequency conversion and analog-to-digital conversion also will be stressed. We hope that the two-part series of articles mentioned above will
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Now, Side-window arrangement in a reliable photomultiplier tube (S-20) by Hamamatsu Expand the wavelength range of your spectrophotom eter with the new HAMAMATSU R-446 Side-Window Photomultiplier Tube. S-20 response —185-850 nm. Standard direct replacement requires no adaptation. The R-446 eliminates the need for several differentrange tubes or time-consuming interchanges. When your UV spectrophotometer analyses require wider wavelength coverage, lower noise, and/or higher sen sitivity, plug in the HAMAMATSU Side-Window R-446 and get all the response you need. Dependable, reli able, and available on 48-hour shipment. Write or call Dept. PT-AC11
OCLI Instruments 132 WATER STREET, SOUTH NORWAI.K, CONN. 06854 (203) 853-2224 Circle No. 6 on Readers' Service Card
ANALYTICAL CHEMISTRY, VOL. 43, NO. 1, JANUARY 1971
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