“Carbon-tet” vapor detector

“Carbon-tet” vapor detector

Sept., 1957.] CURRENT TOPICS with the pumping frequency set at 8800 inc. Oscillations and frequency conversion were observed at both the lower frequ...

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Sept., 1957.]

CURRENT TOPICS

with the pumping frequency set at 8800 inc. Oscillations and frequency conversion were observed at both the lower frequencies. The action of the ferromagnetic amplifier can be simulated at low frequencies by a pair of ordinary resonant circuits coupled by a variable inductance or capacitance. Since certain very high frequency atomic phenomena also have this circuit analog, it is possible that the same amplification principle will find applications at frequencies much higher than those presently in use. It appears that ferromagnetic amplifiers can be designed for operation in practically any portion of the microwave spectrum. Preliminary results indicate that the bandwidth is adequate for many applications. Thus, although the new device is still in the experimental stage in the research laboratory, this discovery may lead the way to an entirely new group of ferrite microwave devices.

Inexpensive Exposure M e t e r . General Electric has announced the first American exposure meter designed for the budget-minded, beginners' market. Called the MASCOT II, the direct-reading meter will sell for about $10.00. Photometric engineers at the company's Instrument Department-manufacturers of precision measurement devices for 75 years--describe the MASCOT II as no bigger than a cigaret lighter, but capable of performance well within ASA accuracy standards. The budget-priced meter gives instant "one-answer" exposure readings and is extremely simple to use, the photometric ingineers said. Useful product features of the MASCOT II include a direct-reading scale for both f-stops and the new

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Exposure Values (EVS), and settings for movie cameras at 16, 24 and 48 frames per second.

"Carbon-Tet" Vapor Detector.Medical detection of carbontetrachloride poisoning--potentially four times as dangerous as carbon-monoxide-may be greatly improved through tests conducted by a General Electric engineering medical-team. Carbon-tetrachloride is a chemical used in many consumer cleaning products and in various industrial solvents. Poisoning can result simply from breathing carbon-tetrachloride vapors. Preliminary investigations by the company's Instrument Department engineers and Dr. J. W. Blevins, plant physician, show that the General Electric Halogen leak detector will detect carbon-tetrachloride in the human system more than an hour after exposure to relatively small amounts of "carbon-tet" vapors. Dr. Blevins said other instruments have been used for this purpose, but "the increased sensitivity and accuracy of the H-1 detector greatly improves medical tests for detecting carbon-tetrachloride poisoning." General Electric's detector obtains a quantitative measurement of the gas present as well as a qualitative detection. This, according to Dr. Blevins, has made the instrument applicable to medical uses and extremely valuable to the industrial hygienist for monitoring areas where toxic halogen gases may be used. The supersensitive Halogen leak detector--an instrument used primarily to locate leaks in tightly sealed industrial systems such as refrigerator and air conditioner units--can find a leak so small that only one ounce of gas would leak through the opening in 100 years.