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Re: What do you recommend for FM transmitter antennas?
To: CRTech <crtech@crtech.org>
Subject: Re: What do you recommend for FM transmitter antennas?
From: Mark Croom <markc@newmail.kinshipradio.org>
Date: Tue, 3 Apr 2018 19:56:04 -0500
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I am with Kevin and some of the other posters here, the low-power Shively antennas are useless in the Winter without radomes. I know there is icing even in North Texas at times so I would be thinking about icing performance. I was peripherally connected with a site where we replaced a Bext (Telecom) two-bay circular polarized antenna with a Versa2ne or whatever Shively calls it, using the bathtub radomes.

That went up very nicely, was tunable to pretty nice reflected power, and to the best of my knowledge has been working well. If you're looking for a non-pressurized antenna I think it might be a good choice.

Others have mentioned the Nicom (and Bext) unpressurized cross-arm antennas are fairly broadband but at the band edges, not so much. Especially down low (which was the issue at the site where we installed the Shively (88.3 I think). The old tube transmitter could be tuned around the antenna's issues, the new Nautel they replaced it with, not so much. So the Shively went in and everything got better.

You are in a different class of antenna when you buy an ERI, because they will likely be designed for pressurization and will be best with air dielectric line, pressurized. You are likely to get the best longevity, and my experience is that you still get the best coverage with the ERI rototiller design, but there are ongoing costs involved.

I think, at 4kW ERP, that I would prefer a medium power ERI antenna and a pressurized feed system.

More random thoughts from another random field guy.


On Tue, Apr 3, 2018 at 3:57 PM, Kevin Kidd <kkbroadcastengineering@gmail.com> wrote:
Although I am no fan of Shively lower power products, but have also been very pleasantly surprised with a 4 bay VersaTune that a Class A client had installed purely because it was all the tower would support.

For a full power station, I would stay away from the Nicom, Bext, OMB, etc and go with ERI or Dielectric or even SWR.  I think that you will really be pushing some of the small antenna's with that amount of per/bay power.

I always advocate for a pattern study if the station can afford it.  I can't count the number of FM antenna's that I have found that were mounted in the singularly worst place that could be found.  Replacing the antenna AND positioning it according to a reputable pattern study has improved coverage in almost every case.

Good luck,

Kevin C. Kidd, CSRE/AMD
Lawrenceburg, TN
AM Ground Systems Company  -  WD4RAT
kkidd@kkbc.com  --  866-22-RADIO -- 866-227-2346

On Tue, Apr 3, 2018 at 12:17 PM, Pat Wahl <pwahl@wwib.com> wrote:

been installing the "Versa2une" by Shively. Comes in a kit, quality
heavy stainless, easy to put together and you tune it yourself to any

On Tue, Apr 3, 2018 at 11:26 AM, Dave Land <dave@klvv.com> wrote:
> We're looking at putting in a new FM station soon. I'm wondering what folks
> prefer for transmit antennas on a budget! This will be a 6,000 ERP station
> with about 4,000 TPO so a 4 bay antenna. We're looking at - BEXT,
> Dielectric, ERI, Jampro, Nicom, PSI, Shively, & SWR. Which do you prefer and

Mark W. Croom
Riverfront Communications, LLC
Yankton, SD
Follow-Ups: Re: What do you recommend for FM transmitter antennas?
(Andy Larsen <andy@whwl.net>, 4 Apr 2018 13:06:41 -0000)
References: What do you recommend for FM transmitter antennas?
(Dave Land <dave@klvv.com>, 3 Apr 2018 16:26:56 -0000)
Re: What do you recommend for FM transmitter antennas?
(Pat Wahl <pwahl@wwib.com>, 3 Apr 2018 17:17:56 -0000)
Re: What do you recommend for FM transmitter antennas?
(Kevin Kidd <kkbroadcastengineering@gmail.com>, 3 Apr 2018 20:57:25 -0000)
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