Engineers charged with the job of designing a new AM transmitter facility nearly always try to plan for the tallest tower possible. This is not just an ego trip; it's because the taller the AM radiator, the higher the field strength developed in the listening area with a given power.
Transmitting several frequencies from a single broadband antenna system requires the use of a combining system, or combiner, composed of RF filters and interconnecting transmission line. Generally, a combiner can be categorized as branched (star point) or balanced (constant-impedance). These types may use band-reject (notch) or band-pass filters.
It's a cool Monday morning; the first in October, in fact. After opening your office, and after downing the requisite two cups of coffee, you turn on your computer and open them: The dreaded capital budget spreadsheets.
When Northwestern College Radio acquired WMAD, one of the first priorities was to replace the transmitter. Mark Croom reviews the AM-1A.
The article titled "Transmission: Implementing IBOC" in the October 2001 issue of BE Radio is very informative, but one concept in it may need further clarification.
We have all been taught that the load impedance must match the generator impedance in the case of non-DC voltages in order to obtain the most efficient transfer of power. In DC work it seems that loads with an improper resistance fail to work because the supply voltage is too low, or else burn out because their resistance is too low for the applied voltage, and simple Ohm's law applies.
In the early days of radio engineering, it was necessary to calculate every value used in determining coverage and antenna design manually. Slide rules were the norm, and many engineers carried one in a hip holster -- well, almost. My slide-rule case certainly had a belt slot in it.
In an ever-evolving effort to smooth the transition from analog to digital technology, the Federal Communications Commission is proposing to revise its rules to allow broadcast auxiliary services (BAS) to convert to digital technology along with broadcast stations.
I often wonder if Major Armstrong knew what he was giving to the world when he began developing frequency modulation as a public service.
Usually, bigger is better. But in the case of AM towers, taller is not always better. A very tall AM radiator is not always the best radiator. In fact,
Discussions with FM engineers unearthed concerns about radio's future when considered with reference to streaming, DAB/IBOC, RBDS, satellite radio, and
Whoever said, the more things change, the more they remain the same, must have had the FCC in mind. More than 50 years ago, Form 301 was thin and did
Incrementally or all at once, the transition is coming. How digital is your facility?
Like mushrooms after a heavy rain, unwanted reradiators sometimes appear almost overnight in the near field of AM antennas.
At some point in an engineer's career, questions such as How does our signal compare to so-and-so? or, Have we increased multipath along the highway lately?
Matters of impedance are deeply significant in radio engineering. In audio, with lower frequencies, the actual component values are generally considerably
The author Gertrude Stein once said a rose is a rose, is a rose is a rose. Maybe an antenna is an antenna, is an antenna also applies, but an AM antenna
If you have the good fortune to be responsible for the installation of a directional AM station, you will find that there are many important details that
A look at the theory of controlled parasitic reradiators and possible directional arrays using parasitic elements.
Most radio engineers will agree that after the antenna and ground system, transmission lines are probably the most neglected item. For both AM and FM,
Andrew PMT200 DryLine: A fully automatic device that covers systems with volumes from 0.01 to 1700 liters (0.01 to 60ft superscript 3), this dehydrator
Many test instruments have been developed in the history of broadcast engineering. Some have had brief lives; others simply filled the needs that many
A radio engineer's definition of a parasite might be something that obtains its power from another's energy. In other areas of broadcast engineering it
Tower maintenance may not rank up there with your top 10 engineering duties: It's costly and time-consuming. Tower work is usually contracted, so engineers