[TowerTalk] Tower heighth question

[K7GCO@aol.com]

 In a message dated 10.02.00 08:34:08 Pacific Standard Time, 
James.E.Brown@lrdor.usace.army.mil writes:
  Hi Ken,
      I can second your comments about the 6-band, 2-el quad at a relatively 
low
height being (VERY) cost/dB effective. (RIGHT ON) That is my current setup. 
The quad is on an AlumaTower crank-up at 52 feet. (PERFECT) The cost of the 
tower (on sale) plus the quad was about $1600 approximately 3 years ago.  
Zero problems from either one, and everything worked beyond expectations from 
the time it was put up. The 5 HF bands of the quad are fed with a single coax 
line through a 2:1
  "Matching Transformer", which you will probably say detracts from the
  optimum performance. (IT'S EASY TO PROVE) However, it works fine and 
simplifies the set up, cuts down on the parts needed, the weight, the 
potential maintenance, and the cost.  I added the 6th band (6M) a year ago 
with no interaction consequences. This band, of course, has it's own separate 
coax feedline.  On the same mast (aluminum) I have a dual-band VHF/UHF 
vertical and a 2M 4-el quad.  The whole array is so lightweight that I easily 
turn it with a medium duty rotator.  You mention advantages of the quad, but 
also add the short turning radius (8' boom) and light weight to that list.  
Some will say that it is not a robust antenna, however I have had no problems 
in that area despite occasional high winds, ice, etc.and have had zero 
maintenance.  Of course, cranking down the tower helps there. The tower also 
serves as the ground side of a 160M 1/2 sloper and suspension point for a 
low-band
 windom.    Jim     W4LC
   >>
 JIM: You have fully experienced as you say "beyond your expectations" what I 
keep suggesting for a basic antenna system of maximum possible performance 
and at the lowest possible and reasonable cost.  I've used that 2:1 balun and 
it failed at 1500W.  This means your quad was compromised tuned for 100 ohms 
and yes it has good compromise bandwidth.  In a 5 band quad, all feedpoint 
Z's aren't the same with basically the same pattern.  Some are lower than 
normal Z's and their tuning has to really be compromised to raise it to 100 
ohms rather than a no compromise match.  Further more on 10M, the free space 
pattern points down at 35 degrees due to the unbalanced orientation of the 
currents in the 17,15&12M DE's.  If you compared your performance on 10M with 
a 2 element quads free space pattern head on, your expectations will suffer a 
severe readjustment.  You may be pleased with the performance you're getting 
with all the DE's tied together but you have yet to experience the "Pile Up 
Busting Potential Of A Full Performance Properly Tuned Individually Fed DE's 
2 Element 5 or 6 Band Quad with Tapered Spacing."  Every time I think I find 
the ultimate, something comes along and alters my thinking.  When it does I 
jump on it right now. 

You are the only one I know of that added 6M--very good thinking.  I have 
some interesting pattern data I'll send you on all my experiments. Without 
Compromise detuning, you will also be able to rotate the quad and quickly 
determine what direction an unknown station is for peaking purposes with an 
8' boom on 20M.  It's a needed and valuable asset.  It's very hard to do with 
a compromise quad even with a fast rotator that I use.  I used to get answers 
to CQ's from all directions between 30 and 330 degrees running 100W as much 
as head on 330-30 degrees with the DE's tied together. That's not exactly an 
effective beam pattern which was the main goal of our beam investment.  I 
knew what was going to happen when I installed the quad after seeing the 
patterns in Eznec but I had to observe it on the air to satisfy my curiosity. 
 I can easily and quickly determine the Azumith of a station with a "Full 
Performance 2 Element Quad" and I never get an off beam answers running 100W. 
 That is why I say a 2 element 5 or 6 band quad with individually driven 
elements (coax switch on the tower and it's proper support of all the cables 
to the DE's) is the "K7GCO Standard Reference Of Beam Performance" after one 
has spent $1600 as you have.  Every worth while dB you could possibly gain 
over this will cost you a lot of money, higher towers and guy wires of 
expensive Phillistrand or steel guy wires broken up with insulators at 
precise points and worry about turnbuckles breaking (recently discussed in 
TT, and liability insurance--on and on). Those with installations like yours 
don't have all these problems, about 38 dB more $$$ in your bank, peace of 
mind and money for bigger rigs.    

I can put up anything I want and I have the space for 6 more poles.  My first 
main work horse antenna will be a 2 element 6 band quad WITH TAPERED SPACING 
with a coax switch to feed each DE and one heavy coax on a self supporting no 
turnbuckle guy wire 48' tower next to the house.  I'll have a 144/440 
MHz--4/8 element combined quad pointing either out the front or back fed from 
the coax switch--all this with the shortest turning radius of any other 
antenna--8 bands of top performance.  If I point the 144/440 quads out the 
back, they both see the least of each other.  You ran another coax for 6M and 
I presume another was used for the VHF/UHF vertical, 2M quad, Windom or the 
160M L which you could have purchased a couple remote coax switches with.  
You could have saved some money on coax.  Antenna Mart has a heavy remote 
coax switch with at least 9 terminals and maybe more.  I'm going to a run a 
heavy low loss coax to the remote switch more for the 50/144/440 beams than 
the 20-10M quad.  I will also have the ability to switch the quad from 
maximum gain to max F/B which no one seems to have done.  I congratulate you 
for your antenna configuration insights that give you the maximum dB/Bang/dB 
Buck/per band with an 8' boom, moderate tower height and medium rotator.  All 
that money you didn't waste can be put in a retirement account.  When you 
retire, you can buy 6-10 acres and spend it there for a 100' towers and 
monband beams for 6 or more bands for that few extra ego massaging lower 
angle dB's that go off into space to never be heard again--like I just 
did-Hi!  

For just a few more ego lifting dB's at a few degrees lower angle than you 
have, you will need 6-100' towers with mono-banders of 5 elements, constant 
maintenance you may have to hire out, need to make big decisions on whether 
to use guy wires broken up or Phillistrand.  The additional 6-10 acres you 
will have to buy, won't have any shade with all those guys.  The antennas, 
towers, rotator and guys will cost about $100,000 and no spare time working 
on them with little to operate, the land about $100,000--and a divorce.  

After listening to my own advice I'm having 2nd thoughts about it-Hi!  I can 
install the least cost antennas systems of anyone but the land and house in 
SD cost over $100,000 which is far less than most anywhere else.  I'll have 
50' towers with a 6 band quad and I'll have 100' towers with mono-banders on 
telephone poles with wire tracks.  I'm retired, in ery good heath and have 
the time.  Meanwhile back to my packing.  This delayed my moving yet another 
day.  Being or not being contented with what we have needs serious review at 
times.  A remote coax switch on the mast would be a very inexpensive way to 
gain more clout with your all band quad.  K7GCO  
   

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