Miguel VK3CPU - RF Toroid Calculator v0.9g
2D Chart Canvas

RF Toroid Calculator was developed to help users predict the RF characteristics of a ferrite or powdered-iron toroid wound as an inductor or suppressor. It uses the manufacturer's (Fair-Rite & Micrometals) published data including the toroid's dimensions and complex permeability characteristics to predict the component's characteristics.
The calculator has 4 separate display areas. At the top is the chart display for showing frequency-dependent characteristics. Next is the schematic display, where a scaled image of the toroid and windings is presented to help with intuitive design. Next is the control panel section, where the user can select the application type, toroid material, toroid size, wire size, number of windings and excitation voltage.

Inputs via the select widgets: Inputs via the slider widgets: Note: Manufacturers recommend keeping the number of turns (N) to a minimum.

Chart display: The chart title contains manufacturer, size, material and part number of the device.
Calculated parameters are displayed against frequency (log scale). Each parameter may be displayed or hidden by tapping on the legend key. Tapping on a data point will display the parameters for a single frequency.
Schematic display: Scaled representation of the toroid and the windings. Wire gauge and toroid dimensions are provided.
On the left of the display are the following: In the middle of the display are the following: On the right are the manufacturers data for the selected material.
Powdered Iron:
Inductance and reactance values correspond well with those predicted by online calculators such as toroids.info. However, predictions for Q have mixed results when compared to the Micrometals Q-Curve Catalog found HERE. I suggest using their catalog for accurate Q prediction. It has been previously identified that Q values predicted using Micrometal's curve-fit equations do not reconcile with measured Q as discussed here.


Change history:
[16-Feb-22] - v0.9f
* Remove references to transformers. Transformers will be supported by a separate calculator.
[17-Jan-22] - v0.9f
* Added x2 and x3 stacking for 31, 43, 52 and 61 240-sized toroids.
[24-Nov-21] - v0.9e
* Justify tooltips.
[14-Nov-21] - v0.9d
* Updated manufacturers data section to more-closely match datasheets. Also justify to appear like tabular data.
[6-Nov-21] - v0.9c
* Re-enabled PI support.
* Added support for PI Material 17.
[3-Nov-21] - v0.9b
* Disabled PI support due to bugs that need to be fixed.
[2-Nov-21] - v0.9a
* Release 0.9a - Major code refactor to support Powdered Iron toroids.
* Increased resolution of the f-slider, making it smoothly regenerate the dataset.
* Fixed frozen f-slider issue that was occurring in some browsers running on Windows.
* Increased contrast for experimental Ceff and SRF calculations, based on David Knight's (G3YNH) paper.