The Tuned Circuit calculator solves for frequency, capacitance, or inductance given the other two values. Click on the button that displays the desired result and enter the other two values into the other boxes and click on "solve." The impedance of the inductor and capacitor at the displayed frequency is also shown.
The Parallel Resistor calculator is useful for connecting two resistors in parallel to achieve a precise value. Choose the nearest value in your stock that is above the desired value and the calculator will display the value to add in parallel to get the desired resistance. For example, you might need 935 ohms exactly but you only have 1k resistors. The calculator will tell you to parallel a 14,384.6 ohm resistor. You look around and only find 15k. But that gets you very close at 937.5 ohms. But you really need 935 ohms. So, enter 937.5 into the starting value box and the calculator recommends a 350,625 ohms. You only find 330,000 ohms. That gives you 934.84 ohms which is very close to the desired resistance. You might want to measure the actual resistors for best results and remember that cheap resistors can change value slightly when soldered. The calculator works identically for paralleling inductors and also for series capacitors. It usually works best to get the starting value as close to, but above, the desired value. If you plan on adding a third resistor to get even closer, choose the second value above the value recommended.
The L(f) Due To Vibration calculator calculates either the single-sideband phase noise due to vibration given the acceleration sensitivity, power spectral density of vibration, oscillator frequency, and vibration frequency. Alternately, the vibration sensitivity may be calculated for a given L(f). Click on the button for the value to be calculated and leave that box blank. The acceleration sensitivity is divided by 10^9, so enter 3E-9/G as "3."