From time to time, we will share articles about do it yourself broadcasting that have been written
over the years.
Feud over part 15 AM heats up on Radio Info.
Douglas Speaks volumes to the subject.
Douglas's post was pulled almost as soon as it went up.
Methinks that someone else is "obsessed", here!
Agreed, the mounting of a part-15 complainant transmitter "above ground" does indeed extend it's range for exactly the reasons you've stated just as an "omnidirectional" FM array is not ever truly onmidirectional - and the FCC still licenses it as such. Do you visit every FM station with a more than 1db pattern distortion and advise them that they require a pattern study in order to be truly compliant? I'm sure that these pattern distortions do indeed cause a more than 105% ERP (or less than 90% ERP) in one direction or another.
Mr. Fry, I laud your efforts at reigning-in lawlessness but, if you really wish to pursue a worthy cause, I have a long list of real violations (on the order of kilo watts that have gone on for years during which no one has bothered to take corrective actions. In fact, in one instance, a class-A FM replaced (with no FCC filing) a 2-bay array with a 4-bay and did not make any appropriate adjustment of TPO (left it set at 6.3kw into the 4-bay) as compensation. Can we say "12kw. class-A"? In another instance - in the same community - a class-A routinely finds any excuse possible to operate from an unauthorized "backup site" because the additional unauthorized 120+ feet "gives a better signal".
In these two instances alone, the resulting ERPs are easily the equivalent of 12 thousand overpowered part-15 AM transmitters operating at 200% of the authorized part-15 level. Would you like the owner's contact information and will you please police them as zealously as you appear to want to police these poor part-15 operators or, will you do as the FCC has willfully chosen to do (I've been there with them while they were in town and was told by one of their "higher-ups" to "ignore those overpowered stations") and "look the other way because they are owned by a "politically powerful man"?
How about cutting these guys just a little bit of slack, huh? Even at 10 or 20 or even 50 watts, they can't possibly cause the level of interference that the above stations cause on an everyday basis. They may not be "letter of the law" perfect but, then again, I find that their "licensed brethren" can be - and usually are - much more egregious (and willful) violators or rules than these low-power "students of radio". How else would we expect for someone to learn our trade? It certainly is not taught in many schools of higher learning!
Now, I suppose I'll be banned for this but, it is my opinion and I also will respect the opinions of whomever bans me for having an opinion and the freedom to express it. I am sure that you will try to have me banned and, based upon my observations during the past month of lurking, it will happen but, I do far more reading than posting anyway so, I am prepared for the punishment of having an opinion.
Regarding some comments of others, posted earlier...
The subject of the elevated mounting of "Part 15 AM" transmitters continues to be posted because so few people seem to realize its functional effect with regard to 15.219. There is at least an an equal "obsession" shown by the posts of others not wanting to accept this.
Put another way, the field intensity produced by an elevated system using a 10-meter conducting path from its chassis ground terminal leading to an r-f ground buried in the earth is about the equivalent of using an equally efficient transmitter rated for 4.23 watts of input power with the base of the 3-meter whip a few inches above the earth (other things equal).
Probably most people would not claim to be compliant with Part 15 AM when using a transmitter running 4.23 watts. Yet using a 100 mW transmitter on an elevated mount as described above is judged by many to be acceptable and even compliant with Part 15, even though the result can be the same.
It would be useful to their customers if the manufacturers of Part 15 AM transmitters recognized this, and did not suggest elevated mounts for their equipment. One such user who was cited for a long ground conductor under 15.219 even reported that he didn't understand why that happened, as he had followed the manufacturer's advice in his installation.
In any case, this information is not given with the intent to "police" Part 15 AM, but simply to show how it works.
Readers will decide for themselves if/how they wish to use this information.
R.FRY is one of those busybody types, just looking for trouble!