Examining AM, FM, and QAM
No doubt as an engineer you have experienced the “buzz saw” on the AM band from adjacent facilities, particularly at night, or been charged with running your station in digital.
A discussion to demystify some of the elusive language consulting engineers tend to use.
After a decade of discussion, some changes have been implemented.
Jeremy Ruck overviews the basics of AM towers.
Although station personnel do not always have the same level of exposure as our friends who work at the heights, you are nevertheless exposed.
The simple view of interference meaning overlapping signal contours tends to overstate the area of potential interference. Jeremy Ruck explains.
While the FCC designed its pattern modeling method to be reasonably accurate over a fairly broad slice of circumstances in the United States, it tends to fall apart in situations in which terrain is abnormally smooth or cases where a particular propagation path has some fairly significant undulations.
Network analyzers come in two flavors: scalar and vector. Jeremy Ruck explains their use.
Regardless of which antenna you select, the best quality antenna you can afford should be chosen as this is the last item in your transmission chain, and the last point over which you have control of your signal.
The L network is the simplest of the impedance transformation networks, and is the basis for the more complex T, Pi and other types of networks.
The connection between LPFM and translators is a result of the necessary implementation of certain provisions of the Local Community Radio Act of 2010 (LCRA).
No doubt, you have received frequency coordination notices. These notices form one side of the coordination process. It's up to you to follow through to avoid potential interference.
Some important events relating to translators warrant some attention.
The tee network seems almost magical as it has the ability to transform between almost any two complex impedances using only reactive elements.
Jeremy Ruck reviews the basics of directional antenna arrays.
It is prudent to create and maintain a plan for disaster recovery at your facilities, which includes maintaining a strong working relationship with your consulting engineer.
FCC rules, IEEE and NCRP standards are designed to reduce the potential for human danger.
First and foremost in any tower maintenance program is to build a solid relationship with a tower crew; and you get what you pay for. Jeremy Ruck explains.
At the heart of the moment method proof is a computer model using an appropriate software package, however, the moment method proof, is not applicable in all cases or array designs.
FM translator service, since its inception in the very early 1970s, has been subjected to several major technical overhauls.
Understanding the mechanics of your RF program delivery system, and maintaining a keen grasp of the associated fade margin can go a long way to diagnosing the rare, but ultimately problematic impact path failure can have.
One good working definition of the Smith chart is that it is simply a graphical calculator for normalized impedance and associated RF parameters.
The bottom line is that without maintenance, transmission line will ultimately fail. The good news is that with regular and periodic inspections, the likelihood of unplanned failures is greatly reduced.
The bottom line is that Revision G is a good thing, and the standard authors have crafted an excellent standard.