[Elecraft] Elecraft CW Net Announcement

[kevin]

Good Evening,

    It was a good week; my to do list could not keep up with me. I think 
it was the sun.  Mix in a little rain and you get a lot more flowers.  
And hummingbirds.  The sun also sent more ions.  We are currently inside 
a stream of solar wind.  There was an X class flare a few days ago.  The 
ionosphere should be ready for us tomorrow.  QSB will add interest.

Please join us on (or near):

14050 kHz at 2200z Sunday (3 PM PDT Sunday)
  7047 kHz at 0000z Monday (5 PM PDT Sunday)

    73,
       Kevin. KD5ONS






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I am modeling the motion of a charged particle through a magnetic field, 
by implementing the Lorentz Force equation.  Only the magnetic portion 
for now, the electric part comes later.  Using vectors makes the code 
more readable and compact.

This is a rough draft of a streak pattern to display charged particle 
motion:

void streak( void )
     {
     struct spark F;          // Force field
     float q = 1.6e-19;       // Electron charge Ampere*second
     float Me = 9.1e-31;      // Electron mass in kilograms
     struct vt ptC;           // Screen point
     struct pt Fm;            // Magnetic component of Lorentz Force in 
Newtons
     struct pt Vv = vector( 5e5, 0.0, 0.0 );     // 500 km/second
     float dt = 1e-2;         // Seconds

     F.B = vector( 0.0, 1e-5, 0.0 );             // Vertical 1 Gauss field
     Fm = vecMult( vecCrossVec( Vv, F.B ), q );  // Magnetic component 
of the Lorentz Force

     for(int i=0; i<rcount; i++) // Move the ray across display
         {
         SelectObject( bkhdc, pn[ ray[ i ].col ] );     // Choose preset 
pen color

         if(( ray[i].X.x > 100.0 ) && ( ray[i].X.x < 400.0 ))  // In the 
field
             {                                          // F/m = a
             ray[i].X = vecPlusVec( ray[i].X, vecMult( vecDiv( Fm, Me ), 
dt*dt ));
             Vv = vecPlusVec( Vv, vecMult( vecDiv( Fm, Me ), dt );
             }
         else
             ray[ i ].X = vecPlusVec( ray[ i ].X, Vv ); // Move ray to 
the right

         if( ray[i].X.x > 500.0 ) ray[i].X.x = -100.0;  // Arbitrary 
endpoint choices

         ptC = perspective( matrixMultiply( Transform, matTvec( Rot, 
ray[i].X ), View ) );
         Ellipse( bkhdc, ptC.x-1, ptC.y+1, ptC.x+1, ptC.y-1 );
         }
     SelectObject( bkhdc, hpen );                       // Restore 
standard black pen
     }


When this works I will generalize it to animate charged particles in a 
toroidal magnetic field.