=  NOW 30 WPM  =  TEXT IS FROM DECEMBER 2020 QST PAGE 49 =

CONNECTIVITY DUE TO SHRINKING UNDER PRESSURE.  IN THE 1950S, THE WIRE UNDER
SCREW TERMINALS GOT THINNER OVER TIME AND THE RESISTANCE WENT UP, RESULTING
IN HOUSE FIRES.  THIS WAS ALSO A PROBLEM WITH RADIO EQUIPMENT THAT USED
ALUMINUM RIVETS TO ATTACH THINGS, SUCH AS TUBE SOCKETS, TO STEEL CHASSIS.
ALMOST ALL RADIOS FROM THOSE TIMES THAT I HAVE RESTORED HAD DC RESISTANCES
BETWEEN THE SOCKET AND ITS GROUND CONNECTIONS, AND THE ACTUAL CHASSIS
GROUND, IN THE SINGLE DIGIT OHMS RANGE PERFECT FOR CAUSING ALL MANNER OF
PROBLEMS.  BRAZING OR WELDING MAY BE THE BEST OPTION.   SOLDERING IS CLOSE,
BUT DIFFICULT FOR SOME METALS, AND UNPROTECTED JOINTS DEGRADE WITH EXPOSURE
OVER TIME.  ANY MECHANICAL CONNECTION INVOLVING ALUMINUM BEAM CLAMPS OR
OTHER JOINTS SHOULD BE TIGHTENED PERIODICALLY AND APPROPRIATE COMPOUNDS
APPLIED TO ALL MECHANICAL JOINTS, AS WELL AS ELECTRICAL INSULATING MATERIAL
TO PROTECT THE CONNECTIONS.  Q A FRIEND HAS AN 18 FOOT OPEN BOAT THAT HE
HOPES TO PUT ON THE AIR ON 60 METERS.  HE WAS WONDERING WHAT KIND OF
COUNTERPOISE TO USE WITH HIS WHIP ANTENNA.  HE WOULD NOT WANT TO DRILL
THROUGH OR MAKE ANY MAJOR MODIFICATIONS TO THE HULL.   TRAILING WIRES SEEMS
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