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DESIGN, BE SURE TO USE THERMAL GREASE WHEN MOUNTING THE RESISTORS.  DUMMY
LOAD ASSEMBLY AND PERFORMANCE I MOUNTED A FEMALE N CONNECTOR FOR THE INPUT
TO THE DUMMY LOAD, AND THEN I USED A 10 MILLIMETER COPPER STRAP TO WIRE
BETWEEN THE RESISTORS 2 MILLIMETERS FROM THE HEAT SINK THIS HELPED ME KEEP
A CONSTANT IMPEDANCE OF ABOUT 50.  I USED THE MICROSTRIP LINE CALCULATOR AT
WWW. EMTALK. COM/ MSCALC. PHP TO DESIGN THE TRANSMISSION LINE.  TWO
MILLIMETERS IS ABOUT THE SAME THICKNESS OF A PC BOARD, AND THE DIELECTRIC
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CONSTANT OF AIR IS NEAR 1.  A LOWER IMPEDANCE LINE HELPS THE SWR AT 200 MHZ
BUT MAKES IT WORSE ABOVE 300 MHZ.  I USED A SHORT, 5 MILLIMETER WIDE COPPER
STRAP TO THE GROUND CONNECTION AND 14 AWG SOLID WIRE TO THE N CONNECTOR SEE
FIGURE 1.  A SMITH CHART SHOWED THAT WITH A 5 MILLIMETER COPPER STRAP AT
THE N CONNECTOR, THE IMPEDANCE WAS INDUCTIVE UP TO 100 MHZ AND CAPACITIVE
ABOVE THAT FREQUENCY.  I ALSO FOUND THAT THE INDUCTANCE OF THE 14 AWG WIRE
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