‰  NOW 15 WPM  ‰  TEXT IS FROM OCTOBER 2012 QST  PAGE 63  ‰

HEIGHT, WHILE THE DIRECT PATH LENGTH IS CONSTANT.  AS A RESULT, AT SOME
HEIGHTS THE REFLECTED SIGNAL IS IN PHASE AND ADDS TO SIGNAL STRENGTH, WHILE
AT OTHERS IT IS OUT OF PHASE AND SUBTRACTS.  FIGURE 3 IS A SKETCH OF A
GROUND REFLECTION RANGE SHOWING HOW THE RECEIVE AMPLITUDE VARIES WITH TEST
HEIGHT DUE TO GROUND REFLECTION.  WE CHOOSE THE LOWEST IN PHASE HEIGHT FOR
MAXIMUM SIGNAL STRENGTH.  THE HEIGHT OF THE DESIRED MAXIMUM IS CONTROLLED
BY THE HEIGHT OF THE SOURCE TRANSMITTING ANTENNA  IN PRACTICE, THE GROUND
‰  END OF 15 WPM TEXT  ‚