I AM IN NO WAY CONSIDERED TO BE AN ANTENNA GURU NOR DO I CONSIDER MYSELF AS
A 160M PRO. FROM A SHORT ACQUAINTANCE WITH TOP BAND I AM CONVINCED THAT
160M IS NOT FOR SISSIES. IT IS A TOUGH BAND AND AN EVEN TOUGHER CHALLENGE.
ONE THING I HAVE LEARNED WHICH I THINK BEARS REPEATING FOR NEWCOMERS TO TOP
BAND. ANTENNAS ARE THE SECRET.
A REVIEW OF ANTENNA THEORY IS IN ORDER TO EMPHASIZE VALID POINTS ABOUT
TOPBAND ANTENNAS.
1. BASIC CALCULATIONS SHOW THAT THE SIZE OF A SIMPLE 160M DIPOLE IS
UNWIELDY FOR
MOST CITY LOTS.(ABOUT 260 FEET LONG)
2. DIPOLES SHOULD BE APPROXIMATELY ONE FOURTH WAVE agl. WHICH
TRANSLATED TO ABOUT 130 FEET
ABOVE GROUND(THAT IS A SUGGESTED MINIMUM) TOUGH CHALLENGE FOR A
CITY LOT. AN INVERTED
VEE FITS ABOUT THE SAME REQUIREMENTS.
3. ANYTHING LESS THAN THIS IS A COMPROMISE. NOT THAT COMPROMISE IN
ITSELF IS BAD BUT
SHOULD BE RECOGNIZED AS SUCH. THERE ARE SOME CURRENT PRACTICES
THAT ATTEMPT TO LESSEN
THE IMPACT OF COMPORMISE ON 160M ANTENNAS; IE, STUBS, INDUCTORS
ETC. fROM WHAT I HAVE
SEEN ON TOPBAND THERE IS NO COMPROMISE WITH HEIGHT ,ETC FROM THE
SO CALLED BIG GUNS.
4. A MORE EASILY ADAPTED TO CITY LOT OR RESTRICTED SPACE IS A GOOD
SHORTENED VERTICAL.
ANY VERTICAL NEEDS CLOSE ATTENTION TO THE BASE IMPEDANCE MATCH AND
A GOOD RADIAL
SYSTEM. BUT FAR MORE EASILY DEALT WITH THAN A FULL SIXE DIPOLE OR
INVERTED VEE IN SMALL
SPACE. FORTUNATELY, I HAVE ROOM TO PLAY WITH WIRE AND VERTICALS.
MY VERTICAL IS MUCH
BETTER IN PERFORMANCE THAN ANYWIRE ANTENNA I HAVE USED.
NT7Y, EARLE
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