Preliminary investigation on error code rate of high speed digital circuitry caused by electrical contact failure

It is found that one of the most important reasons causing high error code rates in digital communication systems is the contact failure of coaxial connectors installed in the systems. Preliminary investigation into the failed connectors collected in-situ has revealed that the contact failure of coaxial connectors may be caused by many factors, such as corroded products or dust particles on the contact surfaces, and the change of normal contact force caused by relaxation of the spring elements, etc. It is interesting to learn how the contact failure causes high and erratic contact impedance and results in error codes in digital communication systems which are still unknown. The effects of tarnish materials on the contact impedance and also the influence of the contact failure on digital signal transmission are studied theoretically and experimentally. Some of the results and tentative conclusions are presented in this paper.