AND NOW SIGMA The first complete GC line with consistent excellence in performance, adaptable to any analytical need and budget. The SIGMA series from Perkin-Elmer is entirely new, entirely unified. It includes gas · chromatographs, lab data systems, and accessories. Incorporating the latest chromatographic technology and the most recent advances in microprocessors, SIGMA presents major improvements in system control and detector performance.

SIGMA is unique for another important reason. You get identical chromatographic

performance from every instrument in the series because they Ye all assembled from common components and accessories. You can transfer most methods developed on one SIGMA gas chromatograph to any other in the series, with no deterioration in performance. Even the column can be transferred.

Optional SIGMA accessories include an Autosamplerfor liquid sampling, and various systems for gas sampling and column switching. An Automatic Environ­mental Sample System enables air

samples to be analyzed with any of the detectors. There's also a solid sampling system. You can get a wide selection of standard interchangeable columns, both metal and glass-capillary and packed. Everything has been incorporated in the SIGMA concept.

Ask your Perkin-Elmer representative for all the facts on the SIGMA series. Contact him now, or write Perkin-Elmer Corp., Mail Station 12, Main Ave., Norwalk, CT 06856.

SIGMA 1 is the most sophisticated system. It combines one or more gas chromato­graphs with integral microprocessor con­trol and data handling. It can employ all the injector and detector options in the series. A keyboard sets analytical parameters, in­cluding carrier gas flow rates, automatic switching of detector amplifier outputs, and external event timing.

Its microprocessor controls the analyzer units and reduces data for as many as four detectors at once. An internal printer/plotter gives you the chromatogram, analytical conditions, and results.

SIGMA 2 gas chromatographs are multi-detector, microprocessor-controlled in­struments that combine versatility with operating ease. They include dual channel, temperature-programmed systems and can have up to four detectors installed simultaneously. You set the analytical parameters on a keyboard that instructs you in the set-up routine. (Instrument parameters can be stored on a card and entered through a Card Reader Accessory] The microprocessor also provides multi­level temperature programming, digital setting of carrier gas flow rates, and digital reporting of all set and actual values.

A NEW ERA IN GC

GMA 3 gas chromatographs are xiestly priced, but exceptionally versatile, igleordual channel temperature-jgrammed instruments. They come h a wide choice of detectors: flame lization; electron capture; nitrogen/ osphorous; flame photometric; or hot e Accessory amplifiers are available for nultaneous multi-detector operation. A ηρΙβ numerical keyboard sets param-;rs while the microprocessor controls the jtine, so no "impossible" values can be tered.

SIGMA 4 gas chromatographs are excel­lent for routine applications and teaching. They are dedicated isothermal instruments designed for single column, singledetector operation. They are also available with a wide choice of detectors: flame ionization; electron capture; nitrogen/phosphorous; flame photometric; and the new thermistor thermal conductivity for rugged routine operation. Injectors, gas controls and other accessories and options are identical to those used throughout the entire SIGMA series.

SIGMA 10 Lab Data System handles data from any gas or liquid chromatograph. Annotated chromatograms can be ob­tained for any oneofthefouractivechannels connected to it, and multiple data files and methods can be stored. Six time-controlled relays are standard on every channel, and ready signals from gas chromatographs and Autosamplers can be fed back to the system for complete synchronization of automatic analysis. With the optional pro-grammability accessory, you can write programs in standard BASIC. A cassette accessory provides additional storage space for programs, and there's also an RS-232C input/output accessory.

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