The combination of the waves in a single layer coil
It is known that the speed of propagation of waves in a coil of inductance for different frequencies are different, and subject to rather complex patterns, depending on its proportions, the absolute dimensions and material of manufacture. In addition, there may be several types of waves simultaneously: LC-resonance and standing waves. If the first type of waves, given the characteristics of the harmonicscan be calculated simply by the formula of Thomson, the mode of standing waves depends on the design features of the coil is much more complex patterns. For example, the frequency ratio for the floor and quarter-wave mode will be in the range of 1.3-1.8 times.
This calculator allows you to combine two types of waves in a single layer coil given its variety of design features. It is assumed that the tested coil is excited with an inductor located at the bottom (as shown). Unlike the previous version it takes into account more parameters, fixed some bugs, and apply a more accurate formula for determining the inductance and influences the dielectric constant. Now in calculating the insulation thickness of a wire and its diameter. Due to the studies have the opportunity to consider the capacity of land to LC resonance. In this version expanded the range of possible points of intersection of the graphs by laying on the X-axis the ratio of the height of the winding to the diameter of the coil. Just like before, the orange graphs represent possible for a given coil frequency LC resonance, and blue for the standing wave.
At the request of readers added calculation of active resistance at the resonant frequency and the quality factor of the coil.
Another important feature of the new version is the calculation of multiple intersection points simultaneously; they may be formed by several harmonics or the two modes of standing waves: half and quarter wave. This allows the researcher to see the overall picture of all possible options. If you selected multiple harmonics, on the chart they are located on the serial number — from the bottom up. If you select both standing waves, the bottom graph chetveronogo, and the upper half-wave. The intersection of the graphs of the highlighted circles, clicking on which you can get a detailed report on the coil parameters at this point.
The schedule can be focused at a chosen point by disabling unnecessary harmonic modes and standing waves. For example, we are interested in the point of intersection of the second harmonic with a 1/2 wave. Then explore the graph can be set in the "Harmonic LC resonance" values of "2 to 2", and "frequency of wavelength" leave a tick only "1/2". Also, it is possible to activate the "Focus data for that point" and then click "Calculate".
The parameter "Frequency of frequency modulation", the default unit. This means that investigated the combination of harmonic LC resonance with standing waves, and there is no modulation. If this parameter is greater than one, instead of a harmonic LC resonance is investigated harmonics generated by modulation of the fundamental frequency. All the details of this mode are described here.
Separately to highlight the parameter "Capacity ground". He has three modes. 1 — when the ground is disconnected and secluded capacity of the scheme to be connected to the coil, is small. 2 — hand. In this mode, you enter this parameter, based on observations or measurements. 3 — automatic. In this case the program tries to approximate this capacity. On even harmonics of the LC resonance this parameter does not affect the operation of the real coil and is ignored by the calculator.
One of the methods for the calculation scheme, which involves the calculator is here.
Note. The calculator works in test mode. Possible changes and additions.
The materials used
- Volkov V. A. Parts and assemblies of electronic equipment
- Robert Weaver, Numerical Methods for Inductance Calculation, 2016
- Alan Payne. SELF-RESONANCE IN COILS, 2014
- Dielectric permittivity
Screen diameter, mm
The minimum diameter of the screen, mm: