diff --git a/short_antenna.html b/short_antenna.html
index 4f7b413..4c475c2 100644
--- a/short_antenna.html
+++ b/short_antenna.html
@@ -38,29 +38,13 @@
slider widgets.
Inputs via the slider widgets:
- - f : The frequency of operation in MHz.
- - l : Length in percent compared to a half-wave dipole.
- - d : Distance of the coil/inductor from the feedpoint to the end, in percent.
- - AWG : Conductor diameter slider changes AWG from 0-40. Actual diameter displayed in decimal inches and millimeters.
-
- Characteristics on the left are independent of frequency, while the characteristics on the right are dependent on the selected frequency.
- Each of the graphic representations attempt to keep the relative geometry correct, without exceeding the drawing boundary. The coil diameter
- relative to the conductor diameter are representative.
- Calculated dimensions:
-
- - ⌀o : Outer coil diameter (inches)
- - ⌀i : Inner coil diameter (inches) - corresponds to the diameter of the winding former.
- - c : Distance between windings, measured from the conductor centers (inches).
- - ℓ : Length of the coil (inches). Equal to c x N.
-
- Calculated parameters:
- Frequency independent:[L]
- - L : Inductance is calculated using Nagaoka's equation incorporating his coefficient.
- - C : Capacitance is calculated using Knight's 2016 paper on self-resonance and self-capacitance of solenoid coils.
- - Rdc : DC resistance is calculated using conductor length divided by the conductor cross-sectional area, assuming a copper conductor.
- - SRF : Self-resonant frequency (MHz) for the unloaded coil.
- - wire : Length of wire required to wind the inductor.
+ - f : The frequency of operation in MHz. [1.8-57.6 MHz]
+ - l : Length in percent compared to a half-wave dipole. [10-100 %]
+ - d : Distance of the coil/inductor from the feedpoint to the end, in percent. [10-80 %]
+ - AWG : Conductor diameter slider changes wire thickness in AWG. Actual diameter displayed in decimal inches and millimeters. [40-0 AWG]
+ Top left is the length of a single antenna element. (Not including the coil length.)
+ Top right is the length of the entire dipole. (Not including the coil length.))
@@ -320,6 +304,20 @@
ctx.stroke();
}
+ function getFeetAndInchesFromMeters(inMeters) {
+ //
+ var inFeet = Math.trunc(inMeters * 3.28084);
+ var inchesLeft = (inMeters - (inFeet / 3.28084)) * 39.37008;
+ return inFeet.toString() + inchesLeft.toFixed(2).toString();
+ }
+
+ function getFeetAndInchesFromFeet(inFeet) {
+ //
+ var wholeFeet = Math.trunc(inFeet);
+ var inches = (inFeet - wholeFeet) * 12.0;
+ return wholeFeet.toString() + "\' " + inches.toFixed(1).toString() + "\"";
+ }
+
const afront_canvas = document.getElementById("inductor2D");
const fctx = afront_canvas.getContext('2d');
@@ -371,16 +369,20 @@
drawInductor(fctx, wire_x, d_pos, 0.0*Math.PI);
drawArrow(fctx, wire_x - 30, d_pos, 0.5*Math.PI);
fctx.fillText(dipole.distance_meters.toFixed(2).toString() + " m", wire_x - 60, d_pos + 12 );
- fctx.fillText(dipole.distance_feet.toFixed(2).toString() + " ft", wire_x - 60, d_pos - 4);
+ //fctx.fillText(dipole.distance_feet.toFixed(2).toString() + " ft", wire_x - 60, d_pos - 4);
+ fctx.fillText(getFeetAndInchesFromFeet(dipole.distance_feet), wire_x - 60, d_pos - 4);
drawArrow(fctx, wire_x - 30, up_wire_bot_y, 0.5*Math.PI);
fctx.fillText("0.00", wire_x - 60, up_wire_bot_y + 5);
//fctx.fillText("0.00 m", wire_x - 60, up_wire_bot_y + 18);
drawArrow(fctx, wire_x - 30, up_wire_top_y, 0.5*Math.PI);
- fctx.fillText((dipole.length_feet * 0.5).toFixed(2).toString() + " ft", wire_x - 60, up_wire_top_y - 4);
+
+ //fctx.fillText((dipole.length_feet * 0.5).toFixed(2).toString() + " ft", wire_x - 60, up_wire_top_y - 4);
+ fctx.fillText(getFeetAndInchesFromFeet(dipole.length_feet * 0.5), wire_x - 60, up_wire_top_y - 4);
fctx.fillText((dipole.length_meters * 0.5).toFixed(2).toString() + " m", wire_x - 60, up_wire_top_y + 12);
fctx.textAlign = "left";
- fctx.fillText(dipole.length_feet.toFixed(2).toString() + " ft", wire_x + 60, up_wire_top_y - 4);
+ //fctx.fillText(dipole.length_feet.toFixed(2).toString() + " ft", wire_x + 60, up_wire_top_y - 4);
+ fctx.fillText(getFeetAndInchesFromFeet(dipole.length_feet), wire_x + 60, up_wire_top_y - 4);
fctx.fillText(dipole.length_meters.toFixed(2).toString() + " m", wire_x + 60, up_wire_top_y + 12);
//fctx.fillText("0.00 ft", wire_x + 60, down_wire_bot_y );
fctx.fillText("0.00", wire_x + 60, down_wire_bot_y + 5);