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PROCESS TO CABLE AND NEST EACH OF THE FOUR INNER SECTIONS.  MY DESIGN
INCLUDED TWO NORMALLY CLOSED MAGNETIC LIMIT SWITCHES AT THE TOP OF THE 3
INCH BOTTOM SECTION, SPACED TO ALLOW EITHER 8 OR 6 INCHES OF TUBING OVERLAP
AT MAXIMUM EXTENSION.  THERE IS A SINGLE LIMIT SWITCH AT THE BOTTOM OF THE
SAME SECTION, AND IF ANY LIMIT SWITCH IS OPENED, POWER TO THE WINCH MOTOR
IS INSTANTLY CUT.  ITS NOT NECESSARY TO WATCH OTHER SECTIONS BECAUSE ALL
MAST SECTIONS MOVE SYNCHRONOUSLY AND ARE THE SAME LENGTH.  A FINAL FAIL
ƒ  QST DE W1AW  ‰
SAFE BOLT WAS ALSO INSTALLED TO PREVENT THE SECTIONS FROM ACCIDENTALLY
COMING APART EVEN IF THE TOP LIMIT SWITCHES FAIL.  A BOTTOM FAIL SAFE IS
NOT NEEDED, BECAUSE THE SECTIONS ARE HARD STOPPED WHEN THE PULLEY HOUSINGS
NEST TOGETHER.  ALL LIMIT SWITCHES AND THE SAFETY BOLT WERE INSTALLED ON A
SIDE OF THE TUBING AWAY FROM THE PULLEYS AND CABLE RUNS.  I FOUND THAT IN
ORDER TO MOUNT THE LIMIT SWITCH MAGNET AND FAIL SAFE BOLT ON THE FIRST
‰  END OF 13 WPM TEXT  ‰  QST DE W1AW  ƒ