[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [IRCA] Short antenna radials
- Subject: Re: [IRCA] Short antenna radials
- From: "Mark Durenberger Mobile" <Mark4@xxxxxxxxxxxxxxx>
- Date: Sun, 1 Dec 2013 13:59:01 -0600
No...that's referring to the Day "Franklin."
The tower height is related to the frequency. To build a Franklin you'd
need twice the "normal" tower height, so a Franklin or "Baby Franklin" are
practical only at the higher frequencies where wavelengths are shorter.
(FYI: KSTP's nighttime array uses antennas that are closer to the 'normal'
length for 1500...though a bit short).
So, yes, KSTP's high tower height is because they chose to install a
Franklin-type antenna. SE Hubbard wanted to give his station every
advantage. While being on 1500 is a disadvantage (compared for example to
WCCO at 830)** the use of a Franklin approach helped to slightly overcome
that difference.
** Some propagation charts suggest there's a 6 db difference between
coverage from 830 and 1500. That would mean KSTP (using a normal antenna)
would have needed 4 times WCCO's power, or 200,000 watts to match WCCO's
Field Strength. (Of course in the practical world the difference is
probably not that great.)
Mark Durenberger
On the Road
-----Original Message-----
From: Forrest Skaine
Sent: Sunday, December 01, 2013 1:02 PM
To: IRCA Mailing list for the International Radio Club of America
Subject: Re: [IRCA] Short antenna radials
Did you mean that KSTP night facilities? I'm just trying to understand
because I'm just an amateur. If it is their day facilities is it because
that tower is taller than most?
Confused,
Todd in Woodbury Mn
Sony ICF 2010, Toyota car radio
On Dec 1, 2013 8:37 AM, "Mark Durenberger" <Mark4@xxxxxxxxxxxxxxx> wrote:
To add to Dennis' info: The KSTP antenna was/is a 179.4/179.4 and appears
to be considered a "Sectional" rather than a Franklin by the FCC.
Nit-picking' I guess.
Happy Holidays!
_______________________________________________
IRCA mailing list
IRCA@xxxxxxxxxxxxxxxx
http://montreal.kotalampi.com/mailman/listinfo/irca
Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers
For more information: http://www.ircaonline.org
To Post a message: irca@xxxxxxxxxxxxxxxx