TRAP-dipole - the W3DZZ antenna for 40 and 80 meter band - updated nov. 2010

HOW TO....

Before you start, bee sure that you know exactly where you would hang the dipol.
I hang it in the tower up 9 meter, and the ends is inverted to about 4,5 meter over ground
with an angel about 140 Deg. in feedingpoint. 
I have added a BALUN in the feedingpoint to match 50 Ohm's COAX-feeder.

  1. Make the 40 m dipole on the spot, with 2 x 10,1 meter loudspeaker-wire 2 mm .
  2. Cut it to Resonans at 7.05 MHz.
  3. Mount the TRAP's ( see DOWN here...)
  4. Mount the rest of the dipole for 80 meter, 6.7 meter in each end
  5. Cut it to Resonans at 3.6 MHz

Feb. 2011:  I made TRAPS to extent the antenne with 160 meter band.


Makinge the TRAP's

 

Resonans on Homemade SpectrumAnalyser:

A clean HI-Q COAX-resonator made after the program: Coaxial Trap Design, by Tony Field (VE6YP),  (582 Kbytes)

Freq.Marker:     7.05 MHz
GRID:                  10 db / 50 KHz div.

 

Measuring VSWR at 3.6 MHz 

CALIBRATING the Cable:

 Measuring the TRAP-Dipole:

 Best VSWR at 3.6 MHz = 1:1.13

 RETURNLOSS: 24.45 dB

 

Usable from 3.5 MHz to 3.73 MHz

 

Measuring VSWR at 7.0 MHz 

CALIBRATING the Cable:

Measuring the TRAP-Dipole:

 Best VSWR at 7.08 MHz = 1:1.11

 RETURNLOSS: 25.9 dB

 

Usable from 7.0 MHz to 7.2 MHz

 

 

Good Luck

VY 73 de OZ6YM, Palle