[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: Variable Capacitance and Inductance
Original poster: "Ed Phillips by way of Terry Fritz <twftesla-at-qwest-dot-net>" <evp-at-pacbell-dot-net>
Just thought of something else related to this topic. Precision
resonant-cavity microwave frequency meter are capable of measurement
accuracies measured in parts per million. It is often impractical to
seal them hermetically and it is then necessary to correct the
measurements for barometric pressure, humidity, and temperature. The
corrections are very tiny!
As an example, the dielectric constant of dry air at 68° F is
1.000536. That means the capacitance change of an air dielectric
capacitor due to reducing the air pressure to zero or increasing it to
two atmospheres would only be +/- 0.05%. Corrections under normal
conditions will be much smaller than that.