compared to hand reading of instru ment analyses. The digitized infrared spectropho tometer, built around the Perkin-Elmer Model 2 2 1 and 4 2 1 instruments, con sists of two shaft encoders and a digi tal recorder. The shaft-to-digital en coders are mounted on the spectro photometer. They take the analytical readings of the instrument, such as wavelength and transmittance, and translate them into digital data. The data are then fed into the digital re corder which converts the information into proper format for punch tape readout for use by a conventional computer. The encoders can be used on al most any instrument or device which produces data as a shaft position, voltage, or count. The encoders, how ever, must be integrally linked with a specific instrument. Perkin-Elmer Corp., Norwalk, Conn.
Environmental C h a m b e r The chamber is useful for testingsemiconductor and electronic compo nents and is built to actual require ments to suit a specific need. For simultaneous tests, the chambers can be stacked one on top of the other. Addi tional instrumentation—i.e. recorders, counters, timers, and program controls —can be easily attached. Modern Lab oratory Equipment Co., Inc. 1809-11 First Ave., New York 28, Ν. Υ. 420
FRAME CLAMPS* Single set screw Precision, all-purpose counter, 2 0 megacycle measures frequency pe riod, multiple period average, and frequency ratio. The counter is equipped with its own time base and a crystal oscillator which can be re placed by a 1-megacycle signal from a primary frequency standard, if in creased accuracy is needed in critical applications. A rear panel connection allows complete control of the instru ment from a remote location. Low power requirements and plug-in printed circuit boards for all active circuits are other useful features. Model 5 2 4 3 L . Hewlett-Packard Co., 1501 Page Mill Road, Palo Alto, Calif.
421
Front-adjusting Five types build any fran Prices, details in Catalog 80A150. Another labware specialty
from
*Patent applied (or
FISCHER
& PORTER
COMPANY
GLASS PRODUCTS DIVISION 1572 County Line Road, Warminster, P a . Circle No. 103 on Readers' Service Card
VOL. 34, NO. 8, JULY 1962
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103 A
