VARIABLE PRECISION METAL-FILM RESISTORS
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)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 30, 1961
- Accession Number
- AD0265848