Don't forget about RBN possibilities for checking signal strengths.
73, Larry W6NWS
-----Original Message-----
From: Robert Harmon
Sent: Friday, August 28, 2015 1:33 PM
To: Ham - Tower Talk
Subject: Re: [TowerTalk] 80 meter inv V
Jim,
I see your point. I have easy to install (and extend up in the air)
telescoping supports for the ends of the V.
I've found I can go from 10 feet to 38 feet with them. I am going to test
the antenna at 10 foot high
ends and then 38 foot high ends. I have a ZL friend in New Zealand that
will give me the signal
differences. It will be a fun test to see what happens. I have a big
Johnson matchbox in line to
match any increase in SWR.
Thanks to you and Marsh for the info. I will let you know the results.
73
Bob
K6UJ
On Aug 28, 2015, at 7:04 AM, Jim Hargrave <w5ifp@gvtc.com> wrote:
Another consideration: As you increase the apex angle, the feed
impedance will increase and the radiation pattern will no longer be
Omni-directional. A Mismatch can result in offsetting any expected
gain and the radiation pattern might not be in the desired
direction.
An Apex of 90 degrees provides a good 50 ohm match and near
Omni-directional pattern.
I have used successfully used Inverted Vs and Slopers for 61 years
and subscribe to the college of hard knocks: Try it, If it works to
your satisfaction, be happy. That gives you bragging rights. In
1954 we never heard of EZNEC, but the antennas didn't know the
difference.
73, Jim - w5ifp@gvtc.com
-----Original Message-----
From: TowerTalk [mailto:towertalk-bounces@contesting.com] On
Behalf Of Marsh Stewart
Sent: Thursday, August 27, 2015 10:16 PM
To: 'Marv Shelton' <marvs@att.net>; 'Ham - Tower Talk'
<towertalk@contesting.com>
Subject: Re: [TowerTalk] 80 meter inv V
Suppose the ends of the 80M inverted V were each raised to 90
feet - the height of the apex of the original inverted V. The
apex
angle would increase to 180 degrees and the antenna would be a
flat-top dipole. The elevation angle of maximum gain would
decrease. At elevation angles lower than the maximum gain angle
the gain would also increase. The original post as I understood
it
was about increasing gain at lower elevation angles for better DX
performance.
73,
Marsh, KA5M
-----Original Message-----
From: TowerTalk [mailto:towertalk-bounces@contesting.com] On
Behalf Of Marv Shelton
Sent: Thursday, August 27, 2015 9:21 PM
To: towertalk@contesting.com
Subject: Re: [TowerTalk] 80 meter inv V
Doesn't the take-off angle increase as the apex angle increases?
Sent from my iPad
And YES it's cool!
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