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[TowerTalk] Re: Excessive Band Aids

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Subject: [TowerTalk] Re: Excessive Band Aids
From: (
Date: Thu, 14 Jun 2001 11:35:50 EDT
In a message dated 6/11/01 2:51:14 PM Pacific Daylight Time, 
    << On 6/8/01 5:10 PM, at wrote:
      >used no TT Band Aids and have spent the .....
     This seems to be a catch-phrase for you, Ken. You've used it in several 
     Frankly, I've been a charter member of TowerTalk (virutally) since it's 
     inception, and I've never seen anyone advocate any "band aid" approach 
     tower or antenna design.
     Indeed, the governing phylosophy of this list appears to be to do things 
     RIGHT. Doing the job right often means it costs more, but there are 
     substantial dangers to equipment, property or life doing it any other 
     Now, prop-pitch rotators are most definitely over-rated for the vast 
     majority of tower installations, so it is no wonder that they perform 
     superbly in that service. They are also as scarce as hens-teeth. And 
     I'm sure your 55-year-old prop pitch rotators will be giving fine 
     to your grandchildren's heirs, but not all of us can afford, nor need 
     The new bell-housing rotators are also absurdly expensive, but it is a 
     lot easier to find used ones in servicable condition, or to bring back 
     one to condition yourself. (My Ham-M cost me less than $50 recently, 
     a couple hours of work to service it) If a few aerodynamic tricks make 
     the bell-housing rotators perform better, that's not a "band-aid", but a 
     good idea. Let's save those prop-pitches for when we really need them. 
     I thought no one would ever ask.  It applies to fixes on mostly an 
"inadequate electrical or mechanical design or equipment".  "If something 
needs fixing or beefing up--It's inadequate."  (Old K7GCO Axiom)  
  I've used the "Catch Phrase Band Aids" about 50 times in the past 1 1/2 
years relating to just specific repairs to what it infers.  What have you 
been reading?  I had a specific discussion with you on this very point where 
you were defending the use of rivets in general and 2 in line to secure 
telescoping elements when the larger one is less than .058" wall.  The 
element is relatively rigid in only one plane where with hose clamps it's 
rigid and secured it in "ALL 360 Degree Directions".  Aluminum pop rivets of 
the diameter used are not a secure device for something with stresses--24 hrs 
a day.  Hammer rivet (not pop rivets) are more secure if large enough and are 
used in airplanes.  Getting behind them with a bucking bar is impossible 
inside elements.  As a Quality Assurance Engineer at Boeing I worked with and 
ran failure tests on all kinds of rivets and know exactly all of their 
limitations of each and every design which I tried to get across to 
you--repeatedly at the time with no success.  TT was full of "Failure 
Reports" which should have been enough to convince you of their limitations 
yet you continued to defend them.  The manufacture even eliminated the use of 
some of them.  They are fast and cheap to use in manufacturing and kit 
building but don't hold up unless they are what I call are "over size" and 
even then I don't use them on antennas where things can wiggle 24 hours a day 
with various loads on them.  "They Failed"--that's the "Big Clue" of 
inadequate design.  "Longevity and No Maintenance" should be the design goals 
we strive for and demand from manufacturers.  I've been oriented that way 
since the 30's as a nickel a day allowance (and what I could earn) "Radio 
Pension" had to be stretched as far as I could during the Depression and WWII 
where there were "no replacements."  I still have my original open wire line 
I made.  It was very cheap to make, has the "same low loss now" even with 
high SWR it had back then and now, doesn't need all those charts telling of 
"increased loss in coax with higher SWR on TT" and has never needed a repair. 
 Come to think of it I did break a spacer one time.  That open wire line has 
probably carried more RF than any ham feedline in history.  I've broken a 
wire on another open wire line and a "soldering job" was all that was needed. 
 Actually coax is just a fad and will go away.  Hold it I'm just kidding.  
Some have taken that seriously and got all upset.  Open wire line (the good 
stuff) is now being sold you know.  If you learn how to use Antenna Tuners, 
certain feedline lengths, techniques I suggest and don't listen to the poo 
pooers who haven't, you might like the results.  All those fancy and very 
expensive coax connectors for the big expensive coax just go away.  I'm 
trying to save you money.   
A recent "TT Band Aid" discussion had to do with the Prop Pitch Motor or I 
should say the "lack of use of it" from my standpoint.  There have been many 
many discussions on all kinds of extra beam, rotator, guy and tower stresses 
when a beam is unbalanced to the wind.  All kinds of math lessons are given 
on wind loads to tower and beams--on and on.  I can do the math but I haven't 
had to all these years because I had the good sense or luck from day 1 to use 
properly guyed (sometimes with ropes) (and self supporting towers to 
eliminate guy wire problems dominating TT now) that were perhaps over rated 
and PP rotators that were overrated by your standards.  I can't buy your 
statement "let's save those prop-pitches for when we really need them."  From 
what I read on TT we need them NOW properly installed.
 I beef up booms and elements in the middle so I don't even need cable braces 
(another Band Aid with inadequate boom design initially at least on 20M and 
up) and with my selections they have taken all the winds even with ice 
loading for some 55 years.  I have the same rotators and other parts "still 
working and undamaged."  You need a "realignment of your ratings and 
 Rotators are purposely underrated so that TT would be full of all kinds of 
rotator problems and they would have more of your money over time.  I like 
"one time purchases and NO maintenance."  One rotator mfg asked me for one of 
my proven Antenna Tuner Designs to mfg.  He didn't want to pay anything for 
it either?  His rotator designs were and present employment business 
practices for another company now are on the cheap side also.   
 Any rotator by my standards that lasts 55 years with no signs of wear with 
all kinds of loads (some unbalanced) "is not over rated."  It's rated just 
right.  Smart hams should make every effort to use them and cultivate this 
type of thinking.  They will save a lot of money.  I have 8 PP motors and 
every damn one is converted to higher speeds than 3/4 RPM which I have no 
patients for except for a 75M beam--someday I'll have one.  I use 2-6 rpm 
depending on the size of the beam.  I hear of all kinds of horror stories by 
those who have "never used a properly designed PP system."  You would think 
that by now I'd have found a few or "even one problem they absolutely insist 
I have"?  I say 1 RPM is just enough to not be too slow for most and not 
require bigger gears and brakes--in particular if faster.  I say that is a 
"Band Aid Design" and TT is full of all it's problems.  I speed up even 
commercial rotators and just don't over load them.  I speed up even the small 
TV rotators and it's a joy to see TV antennas spin at 4-5 RPM.  I can peak an 
unknown signal real fast even with a 2 element beam.  I've a couple thousand 
patterns or more on paper and by watching S-meters which I wouldn't have done 
without a fast rotator.  I have Eznec patterns I check out on the air 
inparticular for "nulls" and haven't found a lot of the "null fill in 
surrounding objects" (that many go to great length reporting on TT) in actual 
practice and in Eznec.  The biggest problem is "RF Spill Over" of what I call 
"Band Aid Feed Systems" the creator of it and it's sins which no one else has 
addressed.  Use balanced feed systems and many problems just go away.  That's 
why I like balanced 100 ohm coax into FD DE's on beams and quads.  Balanced 
1/4 wave stubs can be made of several Zo's to use for lower Z feedpoints on 
yagi's.  With "link coupled tank circuits" one can match a balanced or 
unbalanced feedline from 30 to 1000 ohms.  Receivers had balanced inputs 
years ago.  So in some cases an Antenna Tuner is a Band Aid.  It is needed 
for Z loads above 1000 ohms at the end of an open wire feedline when using 
link coupling or a Pi.  Actually there is a way with Hi-Z loads to couple 
directly to the tank with 2 capacitors. 
 I just paid and all time high of $50 (he wanted $75) for a medium PP motor 
at a flee market and there were 3 others there I felt overpriced--$100.  You 
can certainly afford that.  You just need to know how to use them.  It was a 
real mechanical joy converting it and I took a lot of digital pictures of 
each step although I had plenty from the past.  I may publish a Prop Pitch 
Motor Handbook and may do a Maintenance Service on them later as beams are 
getting bigger and Slow Band Aid Rotators are getting real expensive.  It 
appears there will a market for this info.  I just don't understand why you 
say "lets save the PP motors for when we really need them."  What's wrong 
with using them NOW when they would be the cheapest and have "strong 
mechanical rotator clout" (new term I just created) which is always needed.  
Many have to be dragged kicking and screaming into better ways of doing 
things in many areas.
 If "no one is advocating a Band Aid approach to towers and rotators" as you 
claim, how come so many are having so many problems?  A good repair to 
anything is great if it lasts.  Use bigger stuff than recommended and 
problems go away.  There are "No Relectors for PP Motors" and other 
adequately designed products.  I plan to have PP motor info on a future Web 
Site for conversion and use--not repair unless improperly used.  
 I got most of my PP motors real cheap like $10-20, so in 55 years I don't 
have over $200 invested and only one maintenance job where water got into one 
not properly protected.  I overhauled the rusty bearings and it's still 
rotating.  I was recently asked how I kept the water out and I answered him 
by E-mail in absence of a quick picture.  PP Motors "are not scarce as hens 
teeth"-- I see them at every flee market at good prices and when I get time 
I'll buy them up, overhaul them and makes some money. 
 Other TT Band Aids are the transmission line coupling from a BMW to soften 
wind torque's on rotators.  One TTer suggested another Band Aid of a 40' mast 
pile into the tower to "give a little."  You don't need all that with a PP 
Motor.  All this has been known for years.
 All the concrete problems and heavy math that dominated TT are interesting 
and needed for certain installations.  I have suggested telephone poles 
repeatedly with a 2 wire track on the side.  You dig a hole and have the 
Power Co drop it in, fill in the dirt around it and you are done in a hour or 
less.  Be sure and take care of the driver and crew with a few bottles of the 
proper spirits.  If you move, cut it off below the ground level with a chain 
saw, sell it locally and throw a can of "Stump Remover" on it.  The only math 
needed is what was needed to "Buy the Spirits."  The widow doesn't have the 
problem of removing the concrete block in the ground either.  Telephone poles 
are far more acceptable than towers to neighbors I've noticed.
 There has been big discussions of guy wire interference to beams on TT.  It 
does occur and I gave simple solutions.  I have suggested connecting unbroken 
up guys to the top of the tower is not a really smart way to ruin a pattern 
and a major dumb dumb many repeat.  Who says guys have to be connected to the 
top of a tower?--Weak tower Mfgs do.  I say that "if your guys can't be 
connected 10-15' below the top of the tower--your tower is too weak".  The 
lower connection will reduce guy wire interference although I would still use 
a 1/2 wave of Phillistran before the wire guy just to be on the safe side.  
Lower guy connections also make it a a lot easier to install a beam  
 A yagi's basic design involves telescoping joints.  I and many others found 
over the years, joints become lossy and capacitive.  I developed a cleaning 
process for the problem as needed.  I then used the various goops and found 
they helped but some would eventually fail and get hard enough that a file 
was necessary to remove it.  I have ways to check beam performance with 
pattern recorders.  I've used a capacitance meter and a HP low resistance 
meter on the joints.  A regular ohm meter is all you really need.  It will 
show you if the joint is capacitive also--the Xc value is irrelevant.  So I 
got tired of that nonsense and now use a flee market solder on the joints and 
I have "ZERO Maintenance and ZERO Resistance" on the joints--continuously.  I 
believe I'm the only yagi user that can make that statement and yes soldering 
the joints could be called a "Band Aid Fix" but it lasts.  It's the only way 
to solve the joint problem 100%.  Prior to soldering the joints I had a "Saw 
Tooth Performance Curve" created by regular cleaning.  I have run adhesive 
backed aluminum and copper tape over the elements with good results.  I've 
cut long strips of copper sheet, coated it and the aluminum or fiberglass 
elements with contact adhesive and stuck it on there.  You can still buy 
this.  I rotated it slowly in the lathe and wrapped plastic tape around it.  
Shrink on tubing is too expensive.  I noticed reductions in feedpoint Z's and 
a slight resonant frequency change with the copper wrapped elements. This 
adhesive backed aluminum tape is ideal for a strip across the double folding 
joints on TV antennas in the center in the high current area.  It's 
convenience and necessity for shipping would get very resistive.  This would 
show up when running TV antenna patterns.    
 Quads have a "Straight Line Performance Curve."  The joints are soldered and 
there is "never any performance deterioration".  I'm "yagi'd out" after all 
these years, have a family of good designs, and am switching to new 
challenges with quads.  Quads are also very easy to scale to the100 MHz FM BC 
band (or any band) to use RF sources that are on 24 hours a day from all 
directions and you can use your FM receiver as FS meter.  The reason they are 
very easy to scale compared to yagi's is that wire sizes come in very close 
steps.  Model airplane tubing doesn't.  Spacing and length are easy to scale 
with both, diameter steps aren't.  
 I like PFA's-- "Permanently Fixed Aids" and "Controlled Buying and Other 
Pressures" that forces manufacturers to produce better stuff.  Then a 
"Reflector for Fixes" isn't even needed.  E-mail is 50 times more useful than 
regular mail.  Lets make the most use of it which we still can before they 
tax it.  
 I'm just trying to save you money and wasted maintenance time.  There are 
many more Band Aids I could have mentioned but I think you and others should 
have got the message by now.  Bill, do you have any further question?  K7GCO  

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