I used to experiment with antennas more than I do now. Maybe we need to
"normalize" what we call wire. In some experiments I have used copper
coated welding rod (for gas welding not arc welding) in small diameters
as antenna elements on 2m on up in freq. With skin effect and copper
coating this worked OK. ...and yes I have made wire antennas for 440.
You can make a multi-element beam that rolls up quite small (fits easily
in your backpack)and can be unrolled quickly and easily. If below the
treeline you don't need to carry F/G wands.
Patrick N5G
On 4/13/2015 8:36 AM, john@kk9a.com wrote:
You have 420-440 MHz wire antennas?
John KK9A
To: towertalk@contesting.com
Subject: Re: [TowerTalk] More from the M2 antennas quality control file
From: Patrick Greenlee <patrick_g@windstream.net>
Date: Mon, 13 Apr 2015 07:37:06 -0500
I'm not a Yagi guru or an EZNEC modeler. Can someone tell me what 1/16 of
an inch in element length means in performance parameters in the example
below? I have done mostly wire antennas and 1/16 or 1/8 didn't seem to
make much difference.
Patrick NJ5G
On 4/13/2015 7:10 AM, Lizeth Norman wrote:
Bought a 432CP42UG from M2. Would you believe that of 21 pair of
elements, 14 PAIR were the wrong size? 13 pair were 1/16" off. 1 pair
was 1/8"
Never, never again. 700$ waste.
It took me 2 hours of puzzlement to discern the problem.
The bad news is that they have NO WARRANTY WHATSOEVER!!! YOU BUY IT
IT'S YOUR BABY!!!!
See here:
https://www.flickr.com/photos/n3ykf/16913167247/
Looking at the photos, the elements are lying on paper that shows that
the correct measurement as well as what should be the actual
measurement. The elements are all represented.
The assembly diagram shows that 9 pair are 1/16" different from each other.
This screw up makes the wrong element the right size, as well as the
converse.
Good news is that it's a match at 50 Ohms. What sort of pattern and
G/T is anyone's guess.
BTW: There is another problem. Whoever designed the antenna is a liar.
He/she defines the antenna as rated for 100 MPH. The antenna boom is
secured to the cross boom (this is an antenna designed for an az/el
array) by a pair of #8 screws. When the hurricane comes (I live in
FL), common sense says the antenna is history. I will be happy to snap
pics of it streaming downwind of the tower. Who needs an engineering
degree to see this?
FYI: Mike no longer works there. My experience with M2 customer
service has been abysmal. I have owned 4 of their antennas (18 year
time span). Still own 3. Have the receipts if some parasite of a
lawyer wants to see them.
Ask me and I'll tell you the story about how Mike's wife was screaming
obscenities at me AND Mike at the same time, then she hung up. Was
something about the package being 1/3 of the weight I was billed for.
Rip off artist.
Norman J McSweyn n3ykf
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