[TowerTalk] More on "no good" Quads.

[K3BU@aol.com]

There was a recent bunch of postings on Contesting reflector about humongous 
antennas. Here is one describing another "crazy Yuri" case of "useless" 
Quads. 

>>
"A friend of mine, Yuri UA9CI once had a system of 3 band(20-15-10) quads  in
H configuration. That was 4-4 over 4-4. The system was installed on the roof
of a 9 storey residential building using 26 meter tower. He had to take the
antenna due to moving to another flat but now has plans to restore it
possibly next summer. Another big antenna he had up was full size 4 el 40
meters quad. That was a real "killer" on 40 meters during the day hours when
he could hear what nobody else could because of "no propagation".

73, Igor, UA9CDC"
<<

Let me try to avoid another barrage of shoot'em down postings: (:-)

"No way he could have 26m tower on the 9 story building!"
"The Yagis are much better, no way Quads can be any good!"
"Nobody else could hear anything because they had dummy loads for antennas!"
"There is no propagation during the day on 40m!"
"Can he show the gain figures for the Quad? Software (and W8JI) says he could 
be
only .56 dBi better than classic, well researched Yagis! You win!"
"Where is the article describing those imaginary antennas?"
"It's anecdotal, "me feel good," because I put it up nonsense!"
"Oh yea, what is trying to prove?"
????
the nay-sayers can place the variation of other comments seen here previously 
:-)

K3BU rule #1 on Quad arrays. (I may be quoted if proper credit given.) 
Let me repeat my findings and advice on quads.
    Benefit of using Quad (or other similar full wave) loop elements in 
parasitic arrays shows up to one parasitic element behind and one parasitic 
element on the front of the driven element or driven cell (two or more phased 
elements). Beyond that, more gain and performance is gained by adding Yagi 
(half wave dipoles) elements as parasitic directors (or reflectors).

For those from Rio Linda and who have hard time understanding the above 
statement let me 'splain further:
    With single driven Quad element, 3 el. Quad will beat pants of Yagi of 
same size boom. If you want more gain and performance from the Quad antennas 
you will be better off by adding Yagi elements as extra directors. 4 el. Quad 
is still OK if mechanical situation warrants it (nice looking, symmetrical). 
Going beyond that with more quad directors, is a waste of hardware. If you 
want 5 el. any antenna, you are better off (over 5 el. Quad) with plain Yagi 
or to maintain edge (cut through the pileups) - 5 el. Razor.
    So 3 or 4 el. Quads are also excellent building blocks for stacked arrays 
as the UA9CI example above illustrates. Also Ian, VK3MO is presently 
completing 20m vertical 4x stack of 4 el. quads on 200 ft rotatable tower. 
Stay tuned for him, when he fires up. He had stacked Yagis, now he is going 
to put up "no good" Quads. He also has 550 ft per leg Rhombic, there is a 
good base for on the air comparison (unscientific, but real life) tests.
    So if you think that your 7 el. Quad is going to be a killer, not so! The 
7 el. Yagi will beat it. Then only 7 el K3BU Razor Beam can beat 7 el. Yagis 
(on the same boom length). We are excluding curtains and other "weird" 
arrays, in case someone wants to argue that 2000ft two element rhombic can 
top that :-)

    The above rule was discovered and verified by Yuri Blanarovich, then 
VE3BMV, now K3BU, experimentally on 2m models (real antennas, not software 
models) circa 1974. Later it was confirmed by experiments by N6NB and now by 
software simulation by W4RNL and perhaps others.  
    VE3BMV Razors Beams which include: 3 el. Quad, 5 el Razor, 7 el Log Razor 
and other variations are at the present time know to be the maximum gain 
producing antennas per boom length in the category of antennas on a single 
boom using full wave loop elements and half wave dipole elements. They are 
proprietary designs at this time and detailed information will be available 
at some later time.
    Photos of Razors as featured on the covers of CQ Magazine can be seen at 
VE3BMV home page:
http://members.aol.com/ve3bmv/index.htm
    They proved to be remarkable antennas, outperforming Yagis of similar 
size and VE3BMV managed to set many world records in CQ WW and WPX contests 
in single band categories using Razors from the city lot of 46x120 feet in 
the suburb of Toronto.
    This may be contrary to W8JI (and others) teachings, but this has been 
verified on real antenna models on 2m, and later on scaled down 10 - 20 m 
models. 
    After moving to US, Yuri is now K3BU (part of his old ex call OK3BU) and 
is working on the new generation of high performance antennas using 
assistance of computer antenna modeling software and VHF antenna modeling 
range with focus on salt water environment.
    Any (constructive) contribution and experiences on the above subjects are 
welcome and please direct them directly to me (to ease the clutter on the 
reflector) at k3bu@aol.com, they will be sorted out summarized and CREDIT 
GIVEN to contributors.
    Here you have more of it on "no good" Quads, combination of some of 
Yuri's wisdom and press realease like mumbo jumbo to reinforce the point. I 
hope it makes some sense.

Yuri, K3BU

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