RF Engineering
Vertical Radiators
Sometimes we tend to forget some of the fundamental facts of electronic life involving radiation which, after all, are requisite for radio transmission.
Ground systems
The average ground system is quiet, dependable and retiring, performing its work efficiently, without demand for attention. Unfortunately, too many stations try to economize when installing or maintaining ground systems.
Tweaking the antenna system
The last link in the broadcast chain under the control of the broadcast engineer is the transmitter and antenna system. From then on quality of reception is left in the hands of the listeners. Thus it puts the onus of transmitting the best possible signal on the station engineer.
Taming a wild monitor point
When monitor points suddenly exhibit surprisingly high field strength, one's first inclination is to look at the previous logs and ask the technical staff about the monitoring point's history
Forgotten modulation methods
Early in the 1930s French engineer Henri Chireix devised an ingenious method of modulation that he named most appropriately out phasing. It was based on the result of combining two out-of-phase voltages. This produces a fluctuating signal voltage that varies in amplitude as the audio signals change. This voltage, after amplification, drives a power amplifier stage with properly amplitude-modulated RF.
Radio broadcasting and 700MHz
The FCC is auctioning what may be the most important spectrum allocations of our time. This portion of spectrum will be available as a result of the FCC mandate for traditional analog broadcast television to migrate to the new digital HDTV system by Feb. 17, 2009, specifically the portion previously occupied by channels 60-69.
Don't become a statistic
There are many lists extant of precautions to take before working with high voltage pieces of equipment. Lethal incidents may be more often caused by completely unexpected circumstances than from pure, careless accidents.
LEDs Are Here to Stay
Tower lighting requirements, which are specified in part 17 of the Commission’s rules, sometimes come as a financial shock.
The alphabet soup of broadcast engineering
When the early pioneers such as Alexanderson, Fessenden and Marconi commenced the production of non-ionizing radiation no one limited their RF levels, blamed their antenna towers for the deaths of migrant birds, or complained about ugly towers spoiling picturesque views.
The road to antenna maintenance
Before any useful maintenance can be performed it is essential to know how a system is supposed to operate and also know the licensed operating parameters. A copy of the latest proof of performance and the current license are a good place to start.
