ISSN:0034-6748    

DOI:10.1063/1.1751431

出版商:AIP    

年代:1939

数据来源: AIP

摘要:

Voltage stabilizing circuits employing thermionic tubes can be classified into four groups, according to their derivation from (1) the transconductance bridge, (2) the amplification factor bridge, (3) the simple degenerative amplifier, and (4) combination circuits involving two or more of the foregoing classes or utilizing amplified control voltages. It is shown that the variational performance of a stabilizer is characterized by an internal output resistance and a stabilization ratio. The effect of source resistance on these performance parameters is discussed in the general case and expressions for these parameters are evaluated for ten stabilizer circuits, seven of which are original with the authors. All but two of the circuits can be adjusted to yield perfect stabilization and four have also a very low internal resistance. Glow discharge tubes are discussed as bias battery substitutes. A simple a.c. bridge technique which is convenient for the experimental determination of stabilizer performance under normal load conditions is described in an appendix.

ISSN:0034-6748    

DOI:10.1063/1.1751443

出版商:AIP    

年代:1939

数据来源: AIP

摘要:

Constructional details are given of a complete Geiger‐Mu¨ller counting system consisting of a stabilized high voltage supply, Neher‐Harper coupling circuit and vacuum‐tube scale‐of‐eight feeding a Cenco counter stage. The system is entirely a.c. operated. Its resolution time of 6.5×10−6second allows it to follow the G‐M circuit without counting losses. The counting losses in the Cenco counter stage are negligible for random input rates to the system up to 20,000–30,000 counts a minute.

ISSN:0034-6748    

DOI:10.1063/1.1751432

出版商:AIP    

年代:1939

数据来源: AIP

摘要:

A portable sensitive differential manometer is described. The instrument consists essentially of a train of gears from a small jeweled wrist watch movement and a drum covered with a rubber diaphragm. The design is such as to permit the measurement of rapid and slight variations of pressure. The pressure variations may be as small as 0.0012 cm of mercury and as rapid as 15 per second. The above sensitivity may be increased by a factor of approximately 10 by increasing the effective volume behind the moving diaphragm.

ISSN:0034-6748    

DOI:10.1063/1.1751433

出版商:AIP    

年代:1939

数据来源: AIP

摘要:

A mechanical recorder is described having a resolving time of 0.8×10−3sec. It will follow regularly spaced pulses at the rate of 1200 per sec. and should miss no more than one percent of pulses spaced random in time at an average counting rate of 10 per sec. A circuit is also described giving a pulse of short enough duration and at the same time of sufficient magnitude to satisfactorily operate the recorder.

ISSN:0034-6748    

DOI:10.1063/1.1751434

出版商:AIP    

年代:1939

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1751435

出版商:AIP    

年代:1939

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1751436

出版商:AIP    

年代:1939

数据来源: AIP

摘要:

Following A. G. Worthing the spectral emissive power may be obtained from measurements of the reflection coefficient. This method is applicable to the oxide‐coated filament both at room temperature and at normal operating temperatures. For a particular type of filament containing dispersed nickel the reflection coefficient averaged 36 percent independent of temperature and independent of the degree of activation, i.e., the content of free alkaline earth metal.

ISSN:0034-6748    

DOI:10.1063/1.1751437

出版商:AIP    

年代:1939

数据来源: AIP

摘要:

A beat‐frequency oscillator is described which has a frequency range from 5 kilocycles to 1600 kilocycles, and a maximum power output of ten watts. Broad‐band amplifier principles are utilized in the design to obtain an output voltage substantially independent of frequency throughout the range of the oscillator.

ISSN:0034-6748    

DOI:10.1063/1.1751438

出版商:AIP    

年代:1939

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1751440

出版商:AIP    

年代:1939

数据来源: AIP