KX1 #1403 Antenna Project

[Jack Regan]

I have been following the antenna threads since I started building the KX1.
These experiments are based on that thread, the ARRL Handbook 2004, previous
research into commercial verticals and my own experience.

The goals are to find the best antenna for the KX1 under various operating
conitions.

1.       Smallest, lightest, easiest to set up 4 band backpacking antenna.

2.       Smallest, lightest, easiest to set up for 1, 2, or 3 bands for
backpacking.

3.       Most efficent antenna for 4 bands but still backpackable.

4.       Most efficent 1, 2, or 3 band antennas but still backpackable.

5.       Learn Antenna Theory and Practice.  Formulas, Software, Instruments

STARTING CONDITIONS
DUMMY LOAD

BAT FREQUENCY POWER SWR
12.4 3.5005 3.0 1.0
12.4 3.5600 3.5 1.0

12.4 7.0005 2.9 1.0
12.4 7.0580 2.9 1.0

12.4 10.1005 4.2 1.0
12.4 10.1495 4.2 1.1

12.4 14.0005 2.5 1.0
12.4 14.05800 2.4 1.0

38' TRAPPED , FLAT TOP DIPOLE, CUT FOR 7.040 PLUS/MINUS,40' HIGH. FEEDPOINT
IS NEAR THE MAST FOR MY CUSHCRAFT MA5B.  I REPLACED SOME OF THE GUYS FOR THE
MAST WITH ROPE TO REDUCE AS MUCH INTERACTION AS POSSIBLE.  WHEN I TAKE THE
MAST DOWN AT THE END OF SUMMER FOR MAINTENANCE I PLAN TO REPLACE ALL GUYS
WITH KEVLAR.

BAT FREQUENCY POWER SWR
12.4 7.0005 4.2 1.2
12.4 7.0125 4.0   1.1
12.4 7.0255 3.5   1.0
12.4 7.0400 3.3   1.0
12.4 7.0580 3.0   1.0

NOTE: I HAVE MADE SEVERAL QSOS ON THIS ANTENNA WITH THE KX1 ALREADY.

FIRST BACKPACKING ANTENNA. #534 WIREMAN TEFLON COATED ANTENNA WIRE. 29'6"
RADIATOR. 2-29'.6" RADIALS.  THIS WAS BASED ON THE RECOMMENDATIONS OF
ELECRAFT IN THE KAT1 MANUAL BUT WITH 2 LONGER RADIALS.  I INTENDED TO TRY
BOTH ONE AND TWO RADIALS IN THE FIELD BUT IT STARTED TO SPRINKLE SO I QUIT
BEFORE I COULD DO THE ONE RADIAL TEST.  THE LENGTH OF THE RADIALS WAS BASED
ON THE ARRL HANDBOOK RECOMMENDATION OF QUARTER WAVELENGTH RADIALS. 29' WAS
CLOSE TO THE 1/4 WAVE LENGTH FOR 80 METERS.  FUTURE TEST WILL INCLUDE
MULTIPLE RADIALS FOR EACH BAND.

I TOOK THE GEAR TO THE TOP OF STRAWBERRY HILL (AN ISLAND IN STOW LAKE HERE
IN SAN FRANCISCO) AND HUNG THE ANTENNA AS A 45 DEGREE SLOPER FACING THE
NORTH.

BAT FREQUENCY POWER SWR
12.4 3.5600 ? 9.9

12.4 7.0400 3.5 1.1

12.4 10.025 4.3 1.1

12.4 14.000 2.9 1.3
12.4 14.020 2.9 1.3
12.4 14.040 2.9 1.2
12.4 14.058 2.9 MY FIRST FIELD QSO WITH KX1. 449 FROM WA!!!

As this note took longer to write than I expected I'll leave my guesses as
to what the figures mean till later. Now it's time for food and then some
air time!





 

 


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