摘要:

The condenser type of pressure pick‐up for a high speed engine indicator has advantages of simplicity, ruggedness, and frequency response over other types. As used ordinarily, with a d.c. polarizing voltage, fidelity at low frequencies requires the use of a very high impedance input circuit, with consequent troubles from poor stability, low sensitivity, and particularly ignition pick‐up. The latter has required the use of airplane type shielding on ignition systems. These difficulties have been completely overcome by use of a high frequency (several megacycles per second) ``polarizing voltage'' in conjunction with a special bridgedTtype of balancing circuit. TheTelements of this circuit can be built into the pick‐up very simply and ruggedly, thereby eliminating difficulties with capacity changes in the lead wires. The sensitivity of the circuit is such that very little amplification is required. Frequency response is limited only by the elastic characteristics of the diaphragm. Both pressure‐time and rate of pressure change‐time cards can be observed and photographed. The wide frequency response of the indicator makes it particularly applicable to the study of knocking combustion.

ISSN:0034-6748    

DOI:10.1063/1.1751677

出版商:AIP    

年代:1940

数据来源: AIP

摘要:

A new method of interpolation is described which eliminates one tube per scale‐of‐two and does not disturb the equilibrium of the trigger tubes. A resolving time of 10−4second was obtained with a quenching circuit incorporating the desirable features of both the Neher‐Harper and the multivibrator circuits.

ISSN:0034-6748    

DOI:10.1063/1.1751678

出版商:AIP    

年代:1940

数据来源: AIP

摘要:

Formulae are derived for the investigation of the lag between a current pulse through a galvanometer and the galvanometer's deflection. Examples are given, chiefly to galvanometric recording in microphotometry.

ISSN:0034-6748    

DOI:10.1063/1.1751679

出版商:AIP    

年代:1940

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1751680

出版商:AIP    

年代:1940

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1751681

出版商:AIP    

年代:1940

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1751683

出版商:AIP    

年代:1940

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1751685

出版商:AIP    

年代:1940

数据来源: AIP