Acceptable registrations in the queue through March 30 at 9:00a ET have now been activated. Enjoy! -M.W.

Terms of Use have been amended effective October 6, 2019. Make sure you are aware of the new rules! Please visit this thread for details: https://www.mibuzzboard.com/phpBB3/view ... 16&t=48619

antenna lift

The technical side of broadcasting. Think IBOC is a sham? Talk about it here! How about HDTV? Post DX reports here as well.
User avatar
Plate Cap
Posts: 222
Joined: Sat Dec 04, 2004 9:18 am
Location: After the rectifier stack

WTOM Antenna Lift

Post by Plate Cap » Tue Aug 18, 2020 2:25 pm

The removal of the old pylon and the installation of the new antenna with it's new extension pylon went very well. Perfect weather and perfect execution by Legacy Tower and Helicopter Transport Services.

I have a lot of photos and video, but it's just too cumbersome to host them somewhere and post them here.


The box that many broadcasters won’t look outside of was made in 1969 and hasn’t changed significantly since.

Rich F.
Posts: 80
Joined: Wed May 29, 2019 5:53 am
Location: Illinois USA
Contact:

Re: antenna lift

Post by Rich F. » Tue Aug 18, 2020 4:17 pm

CK-722 wrote:
Sun Aug 16, 2020 7:07 pm
... What are you using to determine the field strength? Maybe Rich can chime in on this. ...
Sorry, I didn't notice the recent comments until just now.

The plots below give some perspective about the pattern distortion that can be produced by side-mounting a c-pol FM transmit antenna on a relatively small (24" face) tower. The two sets of four patterns each there in the upper left and upper right corners show how the patterns vary at four azimuth bearings (N/S/E/W), for the conditions studied. Probably the WBCT antenna is mounted on a significantly larger face width tower, and that would distort the patterns even more than shown here.

As a non-D FM station, the FCC bases the operation/licensing/protections of WBCT on a single, assumed, theoretical radiation pattern such as the one shown in the center of the page. However FCC records show that WBCT uses a 12-bay, full-wave-spaced, rototiller-type array as their main antenna.

Note that radiation from elevation angles of 0° to about -5° is the most important in providing good signals to their predicted, normal listening areas.

Image



Post Reply Previous topicNext topic