ISSN:0034-6748    

DOI:10.1063/1.1752511

出版商:AIP    

年代:1938

数据来源: AIP

摘要:

A coaxial line stabilized oscillator that is easily and rapidly adjustable over the frequency range from 70 to 700 Mc per sec. is described. Rugged mechanical construction, substantially complete shielding and coaxial line output connection are other features. With a 316A type vacuum tube, outputs of several watts are obtained over the entire range. Measurements indicate that for best stability it is necessary to tune precisely both filament leads, in addition to providing a highQtank circuit. An optimum resonant length (&lgr;/4, 3&lgr;/4, ···) of line was not found. The stability decreases as the frequency increases, becoming very poor for frequencies near the limit of oscillation of the tube.

ISSN:0034-6748    

DOI:10.1063/1.1752512

出版商:AIP    

年代:1938

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1752513

出版商:AIP    

年代:1938

数据来源: AIP

摘要:

An instrument is described for the continuous transformation to a scale of linear or logarithmic intensity of a galvanometer tracing representing the density of a photographic image. The instrument has few moving parts, and has proved capable of executing the reductions quickly and accurately.

ISSN:0034-6748    

DOI:10.1063/1.1752514

出版商:AIP    

年代:1938

数据来源: AIP

摘要:

A new circuit is described which has applications for operating high speed electric counters by gaseous triodes. No auxiliary contacts are necessary, and the circuit resets itself in a period which is so short that most counters will operate near their maximum speed. The circuit thus has the advantage that it utilizes the trigger action of the gas tube to operate with a very short initiating impulse, and yet does not involve any auxiliary relays or contacts to open the arc circuit after the count has been registered.

ISSN:0034-6748    

DOI:10.1063/1.1752515

出版商:AIP    

年代:1938

数据来源: AIP

摘要:

A device is described for producing very sharply peaked electrical impulses devoid of the curvature at the base so characteristic of condenser discharges and peaked wave forms. The sharp impulse is applied to the grid of a greatly over‐biased vacuum tube, thus only the peak of the impulse is represented by the plate current output. The advantages of such peaks in oscillograph and stroboscope work are outlined. They enable a single oscillograph element to record at least three independent quantities. The paper concludes with a note on irregularities in some frequency sources.

ISSN:0034-6748    

DOI:10.1063/1.1752516

出版商:AIP    

年代:1938

数据来源: AIP

摘要:

Construction and operating characteristics of an ion source of the capillary arc type are described. The source yields 0.4 milliampere of singly charged argon ions through an orifice 1 mm in diameter, which allows, with pumping speeds of 14 liters per second, maintenance of a pressure of 5×10−5mm Hg in the adjacent chamber where the ions are used. The ion beam is easily focused at ion accelerating voltages of 1000 to 6000 volts. The source has been used as part of an apparatus for study of controlled sputtering of metals bombarded by argon ions, and the accompanying secondary electron emission. The source can be used advantageously in a number of analogous researches of a fundamental character, and also has application in the field of engineering and biology.

ISSN:0034-6748    

DOI:10.1063/1.1752517

出版商:AIP    

年代:1938

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1752518

出版商:AIP    

年代:1938

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1752519

出版商:AIP    

年代:1938

数据来源: AIP

摘要:

A high temperature vacuum furnace suitable for spectroscopic investigations is described. A coil of tungsten wire is used as the heating element. Thermal insulation is provided by the use of insulating bricks. Temperatures of the order of 2000°C are attained with a power consumption of 2.5 kw.

ISSN:0034-6748    

DOI:10.1063/1.1752520

出版商:AIP    

年代:1938

数据来源: AIP