Topband: Re: Vactrols and Flag

[k6se@juno.com]

Don, K4KYV wrote:

"The QST article recommends using non-metallic support poles for flags
and pennants.  The 16 ft. high vertical section six feet off the ground
calls for a 20 ft. mast.

I'd be interested to know what some of the folks who have successfuly
built these antennas have used for masts (not including trees)."
==========
Modeling the Flag with two 20-foot metallic support mast shows a slight
degradation in the F/B ratio.  Without the masts, the F/B is about 34.5
dB on 160m and with the masts, the F/B is about 27.5 dB.

A 20-foot wooden tilt-over mast can be made easily from four 10-foot
2x4s.  I built two of these (and a shorter 13-footer) to support the two
point-fed Pennants I erected for the on-air tests I made prior to writing
the article.  The 2x4s can be assembled as follows (each line is one
foot):

          |
          |
          |
          |
          |
          |
          |
          |
          |
         ||| <---- two bolts here
         | |
         | |
         | |
         ||| <---- one bolt (tilt-over swivel point)
         |||
         |||
         |||
         |||
         ||| <---- one bolt (remove when tilting over)
          |
          |
          |
          |

Burying the bottom 3 feet will put the top of the mast at 20 feet.  One
set of rope guys may be attached at the swivel point.

73, de Earl, K6SE