‰  NOW 13 WPM  ‰  TEXT IS FROM JULY 2015 QST PAGE 58  ‰

THEY WILL BE ABLE TO CARRY AS A FUNCTION OF FREQUENCY.  THIS IS QUITE
IMPORTANT IN SOME AREAS OF TRANSMITTER CIRCUITRY, SUCH AS FOR HIGH POWER
INTERSTAGE COUPLING CAPACITORS, IN MATCHING NETWORKS OR FOR SOME FILTERING
APPLICATIONS, AS WELL AS FOR USE IN ANTENNA TRAPS.  THE OTHER IMPORTANT
CHARACTERISTIC IS THE DIELECTRIC LOSS AT HIGH FREQUENCIES.  THE TYPICAL
CAPACITOR IS SPECIFIED BY A DC RATING, AND OF COURSE AT DC, IT ONLY CARRIES
CURRENT DURING CHARGE AND DISCHARGE CYCLES.  AT RF, IF A SIGNAL IS PASSING
ƒ  QST DE W1AW  ‰
THROUGH THE CAPACITOR, THERE WILL BE DIELECTRIC LOSS THAT WILL BOTH REDUCE
THE DESIRED SIGNAL AND ALSO RESULT IN HEAT DISSIPATION FROM THE CAPACITOR.
AT SOME POINT THERE COULD BE ENOUGH HEAT TO DAMAGE A CAPACITOR.  TYPICAL
WORLD WAR II ERA TRANSMITTING CAPACITORS WERE OF LOW LOSS MICA DIELECTRIC
AND HAD THREADED TERMINALS THAT COULD CARRY HIGH RF CURRENT.  I SUSPECT
MODERN CERAMIC DIELECTRIC DISK CAPACITORS ARE SUITABLE FOR LOW POWER TRAP
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