INSTRUMENTATION
Old Reliable
J . he newest, most versatile version of this famous fraction collector, currently serving scientists in more than a thousand laboratories all over the world, is now available for immediate delivery direct to you from Canalco's plant in Rockville, Maryland. W i t h the Canalco 1205 Fraction Collector, you can have accurate volumetric siphoning (2, 5, 10 or 20 ml fractions), timed flow (18 seconds to 2 hours) and drop counting (1 to 400 drops). Interchangeable turntables hold either 150 or 240 test tubes to collect fractions up to either 5 or 20 ml. W a n a l c o ' s own factory-trained technical representatives stand ready to assist in installation and guide you in operation at no extra cost. Canalco thus gives you double assurance of the same dependable, trouble-free performance on which this collector has built its unsurpassed reputation for quality and reliability. A two-year warranty provides added protection. f o r sample collection plus flow analysis, the Canalco 1205 makes an integrated system with Canalco's Wide-Track 85 Ultraviolet Flow Monitor. Available in three models—all with true ratio recorders whose charts are as wide as this full three-column page—the Wide-Tracks give more sensitive detection of both proteins and nucleotides, and cost less, than any other flow analyzers. Options include automatic scale expansion, automatic baseline compensation, extension cables for cold-room use and choice of cuvette path lengths. When ordered together, the Canalco 1205 and Wide-Track come with interconnecting cable for the Wide-Track's event marker pen.
Contact Canaico direct for full details on the Canaico 1205 Fraction Collector and Wide-Track Flow Monitor. Write or telephone:
CANALCO
CANAL INDUSTRIAL CORPORATION 5635 Fisher Lane, Dept. A2. Rockville, Maryland 20852/(301) 427-1515
Sales and Service Offices in · Boston · Houston · New York · Seattle · Chicago · Los Angeles · Pittsburgh · Washington, D.C Cincinnati · Memphis · Cleveland · Minneapolis · San Francisco Circle No. 63 on Readers' Service Card 186 A
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ANALYTICAL CHEMISTRY
Controls on the right side are concerned with initial voltage, damping, current span, electrolysis function, supply current, electrolysis, stop light, working electrode, balance adjust, voltage scan, external scan, recorder input, external monitor, voltage scan range, electrolysis light and supply current per cent of range. An important feature is the use of positive throw, snap action switches which provide an almost instantaneous transition from "full-off" to "full-on." This prevents the constant current amplifier from going out of control due to a momentary open circuit and also prevents a temporary shorting of the cells. It is not possible here to describe all functions of this instrument. Some more pertinent details may be listed. For the controlled current power supply, there are five ranges from 0-10 microamperes up to 0-100 milliamperes continuously with any given range and the polarity is reversible in all ranges. Drift is less than 0.1% of current range after initial warm-up. Current accuracy is 0.21% of current range and reproducibility thereof 0.09%. Current response time, although a function of current selected and cell resistance, is of the order of 1 millisecond. The controlled-voltage power supply, obtainable as an accessory, has an initial voltage of ± 5 volts continuously adjustable over a 10-turn potentiometer. Precision of initial voltage setting is ±10 mv. There are 4 scan voltage ranges of ±0.5, ±1.0, ±2.0, ±5.0 volts per 10" of chart, each with seven scan rates which are 0.5-50, 1-100, 2-200, and 5-500 mv./sec, respectively. The precision of the voltage drive is ±0.5% of range and its linearity is ±0.2%. Among the recorder specifications are a 0.5 second speed for full scale, seven chart speeds from 1-100 seconds per inch, operational a.c. amplifier, and full wave chopper for stabilization. We are pleased to note that Beckman has followed the growing trend to have the recorder scale and up scale pen movement read from right to left. By thus abandoning the sacred Talmudic rite, those of us who are perverse enough can read our final charts from left to right. We expect to hear much in the near future about the research uses of this flexible instrument. With its use and, hopefully, with the appearance of a ready reference compendium, electroanalytical techniques may find applications comparable to more widely used gas chromatographic and spectrophotometric methods.
