Update toroid.html

toroid.html

@@ -74,7 +74,7 @@
             <b><u>Inputs via the slider widgets:</u></b>
             <ul> 
                 <li>AWG : Select the wire gauge. Sliding L-R changes AWG from 40-0. (Defaults to 20 AWG)</li>
-                <li>Nd  : Winding density at the toroid inner-diameter. Controls how many single-layer turns can be achieved around the core. 
+                <li>N  : Winding density at the toroid inner-diameter. Controls how many single-layer turns can be achieved around the core. 
                 Maximum (100%, slider to hard-right) is reached when the turns are adjacent at the toroid's inner radius. (Defaults to 15%)</li>
                 <li>Vrms : The RMS voltage applied to the inductor (Volts). Determines the flux-density (B) and field-intensity (H) within the ferrite toroid. (Defaults to 10Vrms)</li>
                 <li>f : Shifts the frequency of interest of the chart display from left-to-right. Left towards kHz, right towards GHz. </li>