[TowerTalk] Can take-off angle be too low?

[K7GCO@aol.com]

Tom: When there are uncertaincies like this I've had some others take down 
the usually multiband compromize yagi and clean the joints which it has many 
of.  If that doesn't change anything, install another monobander beam of a 
similar number of elements.  Or use one less element.  You may find a 
difference between one beam tuned for gain and one tuned for best F/B at tht 
height.  A 2 element beam will fill each secondary higher angles of the 
Reflction Factors fully.  This way you can determine if your height just 
isn't right.  If the beam works OK on the other bands the coax is probabaly 
OK althought a loss measurement of it with the MFJ Analzyer is always a good 
diea.  

In a message dated 12/10/00 5:08:25 PM Pacific Standard Time, 
cdietz@swbell.net writes:<< 
    My 10M beam at 75 feet is usually my best antenna.  Check your antenna 
and feed line.
 
 Chuck, W5PR
 
 n4kg@juno.com wrote:
  > Here we go again. I find that my TH6 at 80 ft is the absolute WORST
 > performer of all my antennas on 10M, including a TH7 at 40, TH3 at 40 ft 
    fixed SE, 5L10 at 60 ft, and 5L10 at 35 ft fixed on EU.
 > 
 > The 80 ft high TH6 is NEVER better than any of the other (lower) antennas
    on 10M. On 15 and 20M, the TH6 at 80 ft sometimes is a good band 
    opener and closer but is usually not as good at the TH7 at 40 ft or 4L15 
at 
    55 ft when the band has opened up.
 > 
 > During midday, the 40 ft TH7 is often the best antenna on 20M and still 
not 
    a bad performer at night.  I never bother to move a higher antenna to 
Africa
     where the low TH7 works all. For domentic contests, an 80 ft high antenna
 > has a null at 600 to 1000 miles on 20M.  My TH7 at ft 40 is typically 20 
to 
   40 dB stronder into W1, 2, 0 than the 80 ft high TH6.
 > 
 > de  Tom  N4KG in North Central Alabama
 > 
 > (300 miles south of Indianapolis,  20 miles south of Tennessee,  60 miles 
    east of Mississippi)
 > ////////////////////////////////////////////
 > 
 > On Sat, 04 Nov 2000 Logan <cdietz@swbell.net> writes:
 > > > On Thu, 29 Jun 2000  "Tonno Vahk" <tonno.vahk@hansa.ee> writes:
 > > > > How important is it to have the ability of running very low 
elevation 
    angles in upper HF contesting?
 > >
 > > The prevailing wisdom is high antennas open and close the band...Low
 > > antennas when it is wide open.
 > >
 > > In Texas for the path to Europe if one only could have one antenna,
 > > 75 feet would be best on 10-15-20 meters.  I understand this height is
 > > about 55 feet on the East Coast of the US.
 > >
 > > I do a lot of contesting on 10 meters and 75 feet is certainly the
 > > "bread and butter" (best overall) height to Europe from here.  From
 > > this statistic, and since Texas is the center of the World...Well, about
 > > the center of the US for Europeans...I would think 75 feet would be the
 > > best height for a single antenna for working the most US stations in a
 > > contest. That's my story and I'm stickin too it!
 > > Chuck, W5PR ex: KZ5MM
 >  >>

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