A comparison of test procedures for determining dielectric constant and dissipation factor

A cooperative investigation was conducted by Rogers Corp. (hereafter called the Vendor) and NAFI to evaluate test procedures used in determining dielectric constant and dissipation factor of sheet laminate material. The need for this became apparent when inter-laboratory tests revealed serious inconsistencies in results. It was found that test procedures which employ a gap between electrodes and the specimen do not give accurate determinations of dissipation factor, but that with a proper gap choice accurate dielectric constant determinations are possible. One test procedure of those considered was chosen as preferred since it produced the most accurate and reproducible results in determining both dielectric constant and dissipation factor.