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Survey Results - Yagi Beam Combo




Hi Everyone,

Here are the results of the "Yagi Beam Combo Survey" query that I posted
several weeks ago (I am sorry that it took so long to post this). At the
end of the email I have included the comments that respondents sent in. 

-Hank Heidt N4AFL
					    # Users|Construction | Performance | Comp to Other Ants

(E=Excellent,G=Good,P=Poor)
a)	KLM 2M-14C/435-18C 			2   | 2E          |  1E, 1P     |  1E, 1P
b)     KLM 2M-22C/435-40CX 			10  | 7E,2G,1P    |  7E, 3G     |  7E, 3G
c)	M2 2MCP14/436CP30			3   | 3E          |  2E, 1G     |  1 E, 2 Unknown    
d)	M2 2MCP22/436CP42UG 			1   | 1E          |  1E         |  1E
e)	Hygain-Telex 216SAT/7030SAT		4   | 4E          |  4E         |  4E
f)	Home-brew				3   (see comments) 
g)	Other - If so, what?			2   (see comments)

******* Comments *******

>>>>>>>>>>>>>>>>> KLM Antennas:

The pair are so long and subject to sag, I heartily recommend the user
build a truss invloving a fiberglass rod from near the center of the
antenna, that supports a braided nylon or dacron cord connected to the
ends of the boom.  I put a small aluminum turnbuckle on mine to
accomodate tightening if the cord stretches.
--------
The 435-18C mounting plate came with wrong holes drilled.
After 5 years at 15 Km from beach I see corrosion on the KLM 2M-14C balun.
--------
After 5 years I am having difficulties to copy Oscar 10. But not sure if
thisa is really due to antenna degradation. Terrestrial operation seems to
be good.
--------
I think the KLM,s are very good antennas and perform as a quality antenna
should.  I also have an M squared eggbeater for 2m and I use it for the wx
sats and with a preamp it works AOK.
--------
In service 2 yrs no trouble at all. Have been moved several times for
Mir school contacts and loaner, still no problem on reassembly.
--------
I don't think that the antenna are delivering the publish gain.
--------
Depends on which "other" antennas you are talking about!
Better than most, probably not as good as M-squared.
--------
Hank : - This is from an old timer who has been on the satellites since
OSCAR lll, first satellite QSO on March 15, 1965 and I think I can add
something to your survey. I have used home made yagi beams from 3
elements to the present day KLM twins.  Built and sucessfully used helix
antennas from 4 turns (145 Mhz) to 24 turns (435Mhz) with great successs.
Presently have the KLM twins (22C and 40CX) - construction and
reliability is very good.  These antennas withstood wintery, blustery
norther Minnesota winters and now in the mountains of western NC still
functioning perfectly.  The most amazing thing about the 435 KLM 30CX is
that the SWR is absolutely flat.  On my Bird wattmeter that was carefully
adjusted at the Bird facility in Cleveland when I was there a few years
back doesn't even show a flicker when switched to SWR position when
running 100 watts forward. I have had an occassion to visit with other
satellite hams at field day and can say that I feel these ants are much
superior in performance and construction.  the only comment I would make
to the manufacturer is that the use of the stainless steel 'keeper' rings
is a poor choice for those of us who disassemble the antennas a number of
times in the course of the antenna's life. But, I suppose the designers
had in mind a ham who would install them on a tall tower and would hardly
be taking them down every so ofter.
--------
The unit is a single mast 2m/440. Using it a 2m h or ,440 Vert. Rotateup
25 ft from ground
Does a good job for its size and construction

>>>>>>>>>>>>>>>>> M2 Antennas

They seem to be very reliable and mechanically very well constructed.  I
have no basis for comparison, as I've never used any other.  They don't
come with a circularity switcher--that might improve things on some birds.
--------
The M2 has employed superior construction engineering... very impressed.
--------
Actually Hank, I choose my antenna set because of a (then) apartment
location, I do plan to erect a new array with phased antennas in our new
QTH. However, the M2 medium length yagi's perform very well, I can usually
put a good signal thorough AO-10 even at apogee using 80 watts, and a solid
signal through FO-20/29 and AO-27 using 25 watts or less. I believe the KLM
antenna sets are equal across the board compared to my M2 array.
--------
M2 2MCP22 / K1FO FO-22TV vertical polarization
This antenna combination has been up for a couple years and never
required any maintenance.  They just perform flawlessly.
--------
1 M-Square 2MCP14/G3RUH 16 turn helix...the best and by
far the mose robust 70cm antenna I've ever used 
see above.  The M-Square is mechanically superior to the
KLM, and the G3RUH is impressive!
--------
M^2 are probably the best built of the "majors".  I just wish someone came
up with something easier to deal with than those damn locking washers.

>>>>>>>>>>>>>>>>> Hygain-Telex:

I have had the Hygain Oscar set up for 3 years , I have contacts on nearly
every amateur    satellite in orbit . Have never used any other brand sat
antenna, but I am very happy with the perfomance of these ant .
--------
I assume you mean for Sat use. KLM .....However, I use a HY-GAIN array because
it was convient. Both beams, polarization switches, Fiberglass boom all in one
package for less money. Its been up three years in New England on a Yaesu
G-5400b with no problems and works well on AO-10 and Fuji birds.
--------
Comments - Generally the Hy-gain set are excellent - the KLM are even
higher gain
but longer so i could not fit them on my setup

>>>>>>>>>>>>>Cushcraft 2x8 element AOP-1:

Extremely poor.  THe antenna goes from being acceptable
on a dry day, to becomming worse than a dummy-load when
even slightly wet.  (I'm not exaggerating.)

The cushcraft seems like a fine antenna when dry.  It's
a bit lacking in gain for AO-13 and/or Ao-10 (usable, but
marginal.)

  When the antenna gets even slightly wet, there is no signal
reception at all, due to severe detuning.  I finally put a 
plastic "trash bag" over the driven elements, and it worked
much better...  :^)

  I would advise against buying one under any circumstances.

>>>>>>>>>>>>>>>>> Other Atennas:

Only built one. 15 element CP yagi's for 436 mhz. Works great.  It is a kg5oa
design.
--------
I don't have any commercial beams, but I can give you
my observations:  the serious guys all have KLMs; the guys who do the pacsats
have eggbeaters and M2 beams; hardly anybody claims to have the Cushcraft
beams, even though they are the least expensive of the bunch



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