David, Tony, et all,
I had the very same trouble with the M2 18xxx yagi's.( I had a
pair of them until Isabell.) I could never get a satifactory answer to the
problem from the folks at m2 either. The best vswr I could get was about
1.7:1. The symptom was identical to what you've described. The antennas
indicated resonance below the band. I tried everything I could think of and
rechecked all the element dimentions etc. Nothing worked. I finally gave
up at put them up on the tower thinking that what I was observing was due to
the close proximity to the ground. It was not. The antenna's behaved
exactly the same at 80 feet plus. The antennas obviously worked but I was
never satisfied that they were optimized. The one thing that I did not do
was to check the length of the RG59 with the "F" connectors. I did not know
the velocity factor of the coax. You may try different length(s) just to
satisfy your curiosity.
If you figure it out please let me know the solution.
GL es 73,
Bill, WF4R
----- Original Message -----
From: "t3" <T3@semarg.ath.cx>
To: <VHFcontesting@contesting.com>
Sent: Saturday, September 10, 2005 4:47 PM
Subject: Re: [VHFcontesting] 2M5WL issues - Advice ?
>
>
> Is that a new antenna?
>
> the M2 antenna's are setup differently then any other...
> the elements are not in line from largest to shortest like other brand
> antenna's
> make sure the antenna is made "by the book" better yet take it all apart
> and follow the
> directions step-by step, i had the same problem, when the elements are
> not installed correctly.
>
> Tony
> NN1D
>
>
>
> Dave Vondrasek wrote:
>
>>While I wait for the Insurance to pay off next week, I've been working on
>>the arrays, this week was bury the cable time. Lot of work, I'm to the
>>point
>>were I have a T-joint to intersect with the Tropo tower and run several
>>cable to the same pipe. SO I figured I'd give the Tropo antenna's a good
>>tuning. The only rig that works after the lightning is a FT-736 I had
>>setting in the closet, so I started at the bottom of the stack and worked
>>up. They are on a hazer system so it's not hard really to work on with a
>>step latter. I got the 5-ele M2 6mtr to tune flat at 50.1, I have the 432
>>tuned flat at 432.1, the 220 is also tuned fine, But I'll be ^&#^*#$ if I
>>can get the 144 antenna to tune. It's showing the antenna is tuned below
>>144.0 someplace. The SWR drops as I tune down the band and I run out of
>>band
>>before it gets to a 1:1. I have moved the two shorting bars from one
>>extreme
>>to the next on the driven element 1/4" at a time and it never moves the
>>SWR.
>>I've changed feed lines and meters and it is just not going to change.
>>Could
>>the fancy sealed feed point be blown somehow ? I didn't have this issue
>>till
>>after the lightning and it's leading me to think that this was the focal
>>point of the strike. There are no burn marks on any of the lines or
>>antennas, but most of the 2meter gear was toasted. No fancy antenna
>>analyzers at this shack so it's radio and meters only. Ideas ?
>>
>>Needless to say I will not be contesting this weekend
>>
>>David - N5ITO / EM23
>>http://david.davidv.net
>>
>>_______________________________________________
>>VHFcontesting mailing list
>>VHFcontesting@contesting.com
>>http://lists.contesting.com/mailman/listinfo/vhfcontesting
>>
>>
>>
>
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