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Re: [VHFcontesting] Tech Help needed

To: Buddy Morgan <beamar@aol.com>, "vhfcontesting@contesting.com" <vhfcontesting@contesting.com>
Subject: Re: [VHFcontesting] Tech Help needed
From: Paul Rollinson <paulrollinson@sbcglobal.net>
Date: Sat, 02 Jan 2021 10:01:28 -0500
List-post: <mailto:vhfcontesting@contesting.com>
Well, misery loves company. Thanks for the feedback.I plan on calling M2 on 
Monday but was hoping to finish this project this weekend. 2m tower still needs 
attention. Hope to work you in January. Btw...is the Orlando hamfest canceled? 
Met you last year. Nice VHF dicussion.Thanks,Paul Rollinson, KE1LI Rollinson 
Associates860-928-5147860-208-8814 Cell/TextPaulrollinson@sbcglobal.net 
Representing Component Part Manufacturers for over 35 yearsSent from my 
Verizon, Samsung Galaxy smartphone
-------- Original message --------From: Buddy Morgan via VHFcontesting 
<vhfcontesting@contesting.com> Date: 1/2/21  9:20 AM  (GMT-05:00) To: 
vhfcontesting@contesting.com Subject: Re: [VHFcontesting] Tech Help needed  
Can't really offer you much help. But, about six months ago, I did what you are 
trying to do with my Five element M2. I did it without adjusting element 
lengths. (I agree, moving the shorting bars out, goes against the grain) Yes, 
the antenna is really made to operate in the low end of the band. Here is the 
best I could do:50.080         1:150.125         1:150.200         1.1:150.318  
       1.3:1Before re-tuning I think I was close to 2:1 @50.318. Doubt if this 
helps you. But, maybe it will spur on an M2 Five Element owner or two.Buddy 
WB4OMG  -----Original Message-----From: Paul Rollinson 
<Paulrollinson@sbcglobal.net>To: 'VHF Contesting Reflector' 
<vhfcontesting@contesting.com>Sent: Sat, Jan 2, 2021 9:01 amSubject: 
[VHFcontesting] Tech Help neededGood morning all, I hope you had a nice 
holiday. Part of prepping for the January contest included taking down the 
stack ofM26M7antennas and tuning them a bit higher to accommodate FT8/4 
frequencieswhere the swr runs close to 2:1 After several hours of tweaking we 
were unsuccessful in elevating thefrequencies. Moving the shorting bars had 
little effect and the elements arecrimped together so shortening them would be 
permanent; I prefer not to dothis. After diving thru the specs, the antennas 
are 6M7 and not the modernversions 6M7JHV. Below is a link to the 
  I'm looking for advice. The manual states that moving the shoring bars 
outwill increase the tuned frequency (which doesn't make sense to me). If 
thisis true, I may experiment with either adding push on rings to act 
ascapacitance hats, electrically lengthening the t match, or swedge on 
lengthsof rod to extend the t matches. The design freq of the antenna is very 
sharp: 49.5 to 50.5MHZ but I can'tseem to stay within 2:1 at 50.315. Running 1 
kw is an issue for the amp. The other, not preferred option is to run a short 
segment of 70 ohm coax asa transformer but I will lose output/receive in the 
form of heat. We hung the antennas about 10 ft in the air to sweep so the 
numbers arefairly accurate. Any help or suggestions would be appreciated. 
Thanks, Paul Rollinson, KE1LIFN41AU860-928-5147860-208-8814 Cell/Text 
<mailto:Paulrollinson@sbcglobal.net> Paulrollinson@sbcglobal.net                
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