Del:
Over the past many years, I've kept copies of "The ARRL
Anenna Book". The earliest one I have is 1954. After thumbing
through those books, it looks like both you and John-W0UN are
right about what an "inverted V" is.
Clearly the ARRL Antenna Book in 1955 (see pages 186-187)refers
to an Inverted V as a 'half rhombic' and 'a tilted wire' antenna,
but the more recent ARRL antenna books refer to an 'inverted V
dipole'. This 'inverted V dipole' is a normal 2-legged dipole
with droopy wire legs...a 'droopy dipole'. See ARRL Antenna
Book for 1970, page 204.
It seems to me as though the common usage nowadays, and for the
past 25 years or so, of the words 'inverted V' refers to the
so-called droopy dipole. As far as I know, don't think I've
ever worked anyone with a non-resonant rhombic, or tilted-V
as it's also known.
73
Dale K5MM
==================================================================
At 06:08 AM 4/28/98 -0800, KL7HF wrote:
>John: A real "Inverted Vee" is an end fed wire that
>is precisely a half rhombic, several wavelengths long, and
>terminated on the far end.
>It was originally called the "Collins Antenna", but that gave
>way to Inverted Vee. What hams call an inverted vee is
>just a drooping dipole, called inverted vee because of it's
>shape.
>de KL7HF
=================================================================
>-----Original Message-----
>From: John Brosnahan-W0UN <broz@csn.net>
To: <towertalk@contesting.com>
>Date: Tuesday, April 28, 1998 4:41 AM
>Subject: Re: [TowerTalk] New Discussion Topic: Dipole secrets
>
>
>(An Inverted V is really a half-Rhombic turned on its side, with the
>earth forming the other half. Somehow we started calling droopy
>dipoles Invereted V's.)
>>
>>Au contraire:
>>
>>An inverted V is a reasonable description of the antenna that is
>>based on a dipole. Calling it a " half-Rhombic turned on its side"
>>is not only more clumsy to say it is also technically incorrect.
>>The rhombic has legs that are MULTIPLE 1/4 Wavelengths on
>>a side (when used in the resonant mode without a termination),
>>whereas the inverted V has only a SINGLE 1/4 wave on a side.
>>In the non-resonant mode the rhombic still has legs MUCH longer
>>that a 1/4 wavelength and requires terminations--something that is
>>never done with an inverted V.
>>
>>73 John W0UN
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