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JOEL R. HALLAS, W1ZR, W1ZR ARRL. ORG  THE DOCTOR IS IN SOME ANTENNAS NEED
LOW RESISTANCE CONNECTIONS TO BE EFFECTIVE Q A FRIEND AND I HAVE GOTTEN
VERY INTERESTED IN BUILDING SMALL TRANSMITTING HF LOOP ANTENNAS.  IS THERE
ANYTHING IN THE AMATEUR LITERATURE THAT DISCUSSES HOW TO IMPLEMENT VERY LOW
RESISTANCE M LEVEL RF CONNECTIONS?  I AM REASONABLY UP TO DATE ON WHAT HAS
BEEN PUBLISHED IN AMATEUR RADIO PERIODICALS ON SMALL LOOP ANTENNAS GOING
BACK TO TED HARTS, W5QJR, ARTICLE, SMALL, HIGH EFFICIENCY LOOP ANTENNAS, IN
THE JUNE 1986 ISSUE OF QST BUT I DONT TRULY UNDERSTAND WHAT IS NEEDED FOR
JOINTS THAT DONT TURN THE HIGH RF CURRENT INTO HEAT.  A FIRST, THANK YOU TO
SENIOR LAB ENGINEER ZACK LAU, W1VT, FOR HIS COMMENTS ON THIS.  THE LOSS
COULD BE INDIRECTLY MEASURED BY CALCULATING THE BANDWIDTH OF THE LOOP THE
NARROWER THE BANDWIDTH, THE BETTER.  ZACKS GUESS IS THAT THE BEST APPROACH
IS TO BRAZE EVERYTHING ONCE, THEN CAREFULLY SAND AND POLISH ALL JOINTS TO A
MIRROR LIKE SURFACE.  ANOTHER PARAMETER IS THE NEEDED DURATION OF THE
CONNECTION, BECAUSE MOST CONNECTION ARRANGEMENTS DEGRADE OVER TIME.  SOME
MECHANICAL CONNECTIONS THAT DEGRADE DUE TO OXIDATION CAN HAVE THEIR
RESISTANCE GROWTH DELAYED BY A COMBINATION OF CONDUCTIVE ANTICORROSION
GREASE ON THE SURFACE AND COVERING THE JOINT WITH SOMETHING THAT KEEPS NEW
OXYGEN AWAY.  SOME ANTENNA MATERIALS, PARTICULARLY ALUMINUM, LOSE THEIR
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