[TowerTalk] (no subject)

[K7GCO@aol.com]

                                           ANTENNEX MAG
         AntenneX has immersed as the most authoritative and creative source
 of Antenna Info there is for the Hams.  Communications Quarterly did well
 for a while but sold out to QST and they lowered it to their standards.  I 
have
 a huge Antenna Library (just shipped 2 tons of it and all other books to S.D)
 and have down loaded most of the articles from the Archives as there were a
 lot of new ideas--even today.  There is no way anyone can be competitive in
 Ham Radio today without a constant study of antennas and being on Reflectors
 like TT and some of the others.  Knowing how valuable the antenna
 information is on TT, I and many others spend a lot of time reading, some 
times
 contributing to TT and reading AntenneX and other material.  I'm down to
 about 5% of my spare time making contacts.  The average "Get Up To Speed
 Time and Antenna Expenses" are greatly reduced for an average new ham by 
doing
 their antenna homework.
 
    There's been a series of articles on 2 element quads in AntenneX by Cebik 
and
 Handlesman that is some of the best work I've ever seen in over 60 year of 
heavy
 reading.  "The 2 Element Quad will rise again".  I've had all kinds of
 small, medium and large antennas and will have a variety of them again in 
S.D.  I
 have no height or space limitations there and I like high performance 
antennas.
 However I have a great interest in the major 2 element beams as at 1/2 wave
 above the ground, they do a great job in particular when tuned for max F/B
 which also results in a very broad vertical pattern ideal for low heights.  
 High F/B is and 2 element gain figures are therefore a highly desirable
 feature of a beam--2 ways.  2 element beam installations are inexpensive,
 affordable and require only a moderate height for a self supporting or guyed
 tower, moderate rotor, low maintenance, one person can install it, are not a
 big eye sore and there is not other antenna in the Antenna Kingdom that will
 outperform them at that height.  I call them the "initial and primary
 antenna" for every ham.  Even if you had a 5 or more element beam up much
 higher on another tower, it would only be used a small % of the time in
 comparison for many.  Low angle is not always the best and during the
 sunspot lows ort even the highs and the higher bands are dead for DX during 
 the lows.  High angle is always "in" full time for the best overall 
performance for
 the entire 11 year cycle.  You can make a lot of great contacts with the 2 
 element beams any time 35-45' high.  2 element beams--in particular
 multibanders--are Ham Radio's Best Antenna Buy--a great "Starter Antenna".
 A high gain beam high in the air is an expensive investment all DXer's need
 and will also not work well close to the ground due to a much sharper 
vertical
 pattern.  Fortunately few install high gain beams close to the ground.  This 
is 
 a concept I have never heard anyone else discuss or read any article on this
 important concept.  2 element beams also work great say at 100' and they 
 fill the higher angle Reflection Factors with far more RF than the higher 
gain
 beams do.  They are just a couple dB down from the higher gain beams on the 
 main lobe.  They are far easier to stack also and one person can install 
them-- 
 or at least I can.
 
    Many DXer's I know who moved to trailer parks have been pleasantly
 surprised with properly designed 2 element beams around 40' high. The Hex
 beam has a bit less pattern and SWR bandwidth than a 2 element quad due to
 compressed wires and no matching device direct feed for 30 ohms with no
 balun.  It's vertical pattern is wider than the 2 element quad but it does a
 great job 35-50 high--in particular the 40M Hex Beam.  I have a great
 matching system for it and with great SWR bandwidth as a bonus.
 
    Multiband beams are a must for basic economy.  Some are bigger
 compromises than others but I claim a smaller compromise when mounted 
 1/2 wave or slightly higher.  2 element beams have a broad vertical pattern 
 which is really not a big detriment--it's a benefit.  It fills the high 
angle 
 Reflection Factor for this height with maximum RF.  Not so with higher gain
 beams.  So do multiband yagi's but they have too many compression joints 
 that can get resistive for me.  
 
    Hams have been constantly brain washed that the highest gain beam
 practical is the only way to go.  That is a total misconception and all the
 2 element beam manufacturers agree with me 100% hi hi.  The 2 element 
 quad will rise again with innovative ideas and advancements thanks to Cebik 
and
 Handlesman.  I may add a few also.  It's actually riding high right now and
 I'm trying to get many of you to "look up", see it and listen to it do it's
 thing.  Progress is always tough and slow but improvements are being laid in
 our hands--take advantage of them now. 
 
    The 2 element quad has one soldered joint/element and 2 contacts for the
 feed line (that could be easily soldered)--no electrical deterioration.  
I've found 
 you can get better patterns with a 5 band 2 element tapered spacing quad 
 than with monobanders.  I even added 6M with some unusual pattern results.  
 Some of the wise ones didn't believe it on TT but even Cebik has verified it 
 and they shut up.  Some years ago I noticed rectangular quads gave better
 gain and wider spacing gave better F/B even with square quads but with a 
 slow computer at the time, I saw the potential there and didn't have the 
time 
 to persue it.  I'm looking at the fastest computer available now for several 
other  
 projects.
 
    Now Cebik and Handlesman have done their homework and developed several
 concepts fully.  There hasn't been any electrical improvement in 2 element
 multiband quads for about 30 years except indiviually driven DE's like 
Antenna 
 Mart does.  Cebik has 2 books coming out with all his data.  The Junk Dealers
 actually reduced interest and popularity in the 2 element 5 band quads by 
 degrading it's design by tying the DE's together and one physical spacing 
for 
 all elements to save money.  It's ruined the pattern on all 5 bands.  One 
has 
 tapered spacing with the DE's tied together.  The same spacing and wires size
 was used on some of them as if that was optimum--it wasn't.  Some were 
direct 
 fed without a balun--the ultimate dumb dumb on any balanced feedpoint.
 
    In addition Cebik has had articles on the affect of wires size which has
 always been what's available.  Essentially the bigger the diameter the
 better 2 ways and this months coverage in November AntenneX by Cebik and
 next month coverage will really cover it.  Tubing is feasible only on 
VHF&UHF.  For
 maximum performance on 80M a 3.5" diameter tubing is needed and not
 practical.  Cage wire construction is feasible on LF loops.
 
    I have done some work with 4, 5, 6 & 8 wire cage antennas for 160&80M and
 solid tubing comparisons in Eznec and I bet this is what Cebik is coming up
 with.  Or he is just adding wires longer and shorter in the same plane in
 the reflector to give somewhat the equivalent to tubing of larger diameter.
 I've done that in the DE to get broader SWR bandwidth.  I can't wait to see 
what
 he's used.
 
    I couldn't be happier at all the work they are going to save me in my
 quest for the Ultimate 20-6M 2 element quad fed with individual coaxes with
 the proper feed system from a coax switch on the mast like Antenna Mart
 does.  Bill Wall and Chuck Smith of Raibeam do everything right--no 
electrical 
 or mechanical compromises.  I will add one wrinkle to my "Ultimate Design." 
 A good F/B dip in the rear only holds for a narrow range of frequency and no 
one else has addressed this problem.  I will use variable Xc's in each 
reflector all ganged together to a selsyn at the mast and obtain the great 
F/B dip possible over the 
whole and on all bands and is around 100 ohms.  Further I can tune the quad 
for
max gain also.  The Z goes down here and is reactive in comparison to the Z 
for
 max F/B.  However my feed system will have uses 100 ohm balanced coax of 1/2
 wave multiples that is fairly forgiving into a Match Box.  This is one of 
the best 
 feed systems going.
 
    Massaging the quad loops rectangularly as Handlesman did is desirable for
 more gain--if you want it.  I've have a 2 element quad configuration with a
 vertical pattern that is as sharp as 3 element beam is on a boom 3 times
 longer.  Yagi lovers--eat your heart out.  It is not exactly what I want in
 some cases on every band of a 2 element 5 band quad.   17&12M have different
 bandwidth requirements being only 100 KHz wide.  This will be an exciting
 research project, I have Eznec Pro now and will have one of the fastest
 computers available.  This beam will have more multi-band performance for
 the boom length than any other 2 element 5 or 6 band beam available without 
any
 SWR or bandwidth compromises.  Actually the 2 element Raibeam's gain on a
 shorter boom is real close, has a good F/B, good pattern and SWR bandwidth
 over the band in their mono and triband beams, great construction and light
 weight.
 
    The 2 element quads and other beams "big dip" in the rear can be deep but
 the next improvement is to get the highest F/B average all the way around
 the back.  I have a great 3 element yagi on a .35 WL boom with no less than 
 30 dB all the way around the back that is the best I've ever seen.
 
    For the next level of improvement I have a 3 element quad type antenna
 that has one of the best F/B's around the back I've ever seen along with a
 big dip of over 90 dB in Eznec.
 
    Big improvements that are easily, inexpensively and finally utilized are
 just around the corner for 2 and 3 element quads thanks to Cebik and
 Handlesman.  I'd suggest you subscribe to AntenneX to keep up with the
 progress of quads and all the other antenna coverage they have every month.
 I have no connection with AntenneX other than a satisfied reader.  Take a
 look at their Web Site and be prepared to spend some time on
 it--"AntenneX.com".  You will find instructions on how to subscribe.  It's a
 Ham's Best Buy in Antenna Info.  I've been reading everything printed in
 antennas for over 60 years and I really look forward to it every month.
 K7GCO

 
 
 


--
FAQ on WWW:               http://www.contesting.com/FAQ/towertalk
Submissions:              towertalk@contesting.com
Administrative requests:  towertalk-REQUEST@contesting.com
Problems:                 owner-towertalk@contesting.com