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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