Accession Number:

AD0265848

Title:

VARIABLE PRECISION METAL-FILM RESISTORS

Descriptive Note:

Corporate Author:

WESTON INSTRUMENTS INC NEWARK N J

Personal Author(s):

Report Date:

1961-09-30

Pagination or Media Count:

1.0

Abstract:

A radical contactor design change was instituted which curtailed investigations of metallic brush designs in favor of graphite brushes. Data obtained indicates wear rates to be reasonable with some initial drop in resistance as carbon deposition occurs. Noise figures obtained are relatively stable for extended cycling periods and are due mainly high contact resistance introduced by carbon deposition. To expedite the testing of this contactor as regards wear and noise, elements were subjected to rotational life under load. Cycling was performed at 25 and 28 cpm on cyclers which do not allow noise testing at 2 cpm. Hand rotation of the cyclers at approximately 2 cpm showed negligible transient noise but contact resistance varied from 100 to 400 ohms. Author

Descriptors:

• *CARBON RESISTORS
• *POTENTIOMETERS
• *VARIABLE RESISTORS
• GRAPHITE
• ELECTRICAL RESISTANCE
• RESISTORS

Subject Categories:

Distribution Statement:

APPROVED FOR PUBLIC RELEASE