Back in the 50s and very early 60s the NH State Police operated WRPT (1650 kilocycles!) in Concord, NH. The transmitter power was, IIRC, 500 watts and the antenna was a series-fed 4-legged self-support, ~270 feet tall, located just behind the sole broadcast AM in the city (WKXL)....with a good receiver you could hear the dispatcher....but NOT the mobile units!!
Alas....the transmitter was retired to the scrap heap....and the tower met the same fate sometime in the mid 80s...I actually watched the tower demolition -- a couple of small explosive charges on the base insulators sent the beast tumbling into the field....!!:(
To expand on Artisan's post, I will draw a parallel here.
A while ago I was stopped for not completely stopping at a stop sign. kind of rolled slowly through.
The officer, after a minite of consultation with me and asking a question went back to the cruiser and a few minites later came back and said:
You were polite, and answered me honestly and I know you weren't deliberately trying to ignor the stop sign so I'm letting you off.....but please watch your stop signs and that was that.
If I had had an attitude or lied when answering a question it would have been a ticket and anything else he could find to get me with.
Willing to bet that the majority of FCC NOUO's are people not using a certified transmitter, deliberately knowing they are illegal, or have the wrong attitude when they show up.
Fortunately in Canada, for people not able to do the more complex set up to get any real range with AM(need to own your own property among other things)) FM allows more range than the USA under BETS-1, not just to your yard. And can be done from anywhere easily. And FM aproches here what you get with AM in the USA and the 1 mile plus some report getting is not with a decent listenable signal. And at night, would be not far at all.
Mark
Willing to bet that the majority of FCC NOUO's are people not using a certified transmitter, deliberately knowing they are illegal, or have the wrong attitude when they show up.
Willing to bet your assumption is wrong.. Well, partially anyway. I highly suspect most (not that there has been all that many) of the NOUOs for the AM broadcasters were actually indeed using FCC certified transmitters - probally either Rangemasters or Procasters, because they are the highest quality AM part 15 turn-key transmitters which are readily available..
Almost every single AM NOUO that I've seen were cited primarily for long ground leads.. the citations never specifies how long, but it's reasonable to assume they were far in excess of an additional 10 feet.
Granted, I don't KNOW this as fact, but I do know, or lets say, I do beleive it with a high degree of conviction.
I agree totally that most of them were fully aware they were operating outside of part 15 limits before they eventually got cited, and a poor attitude nver helps anything.
Certified transmitter is preferable, but it makes little difference as far as legality goes, it's all about how it is installed... and I have become convinced - based on almost 50 years documented common use of part 15 AM whip and mast installs (State Parks, Highway Dept. Sea Grant studies, Atlantic Records promotions, and more).. There is definately a little leinency in play beyond the strict part 15 rules.. probally because it's pratically impossible to abide 100% to specifications and still operate at all.. But what appears to be the real compliance is to abide to the "spirit" of the rules.
Again, this is only my own speculation based on historic observances.
When you have a signal going 5, 6, 10 miles.. whatever, mounted 30-50 feet in the air and saying it's legal because your ungrounded and your within the 3 meter rule.. It's compleately ridiculous, something is radiating. And if such installs become promoted as "Part 15 legal" and people start following the example, and it becomes popular.. the next thing you know the part 15 rules will be ammended to limit the legth of your audio and power leads to put a stop to it. - That's exactly the type situation that caused the ground lead to be written in.
Well... I'm just rambling.. frustrated by a lot of the nonsense I've noticed becoming evident.. and not part 15 on a part15 specific forum. That kind of stuff could lead to a real threat of screwing up what liberties Part 15 provides.
Rememeber, part 15 is primaily a protection device for licensed broadcasters, it's not only a licensed-free broadcasting medium.
I personsally don't care what anyone does, but don't go trying to blur the line between part 15 and piracy, it's damaging to the hobby. That's my only aurgument on the matter.
The citations for extra long ground leads.....makes my point about knowingly having a wrong install. But wonder what would draw a visit in the first place especially on AM with you on your own property, seeing that AM has so few anyway. Someone would have to know about your set up and not like you.
I agree with what you say about someone getting 2 or more miles even with a Procaster or Rangemaster with no ground and saying they're part 15 legal, like that post a bit back with someone having it up on a large tower. Even with a ground and loading coil still 100mW can only go so far. And that's unmodulated. When you start modulating to transmit audio you lessen the range.
As for certification or the technical acceptance certificate that is not as much a part of the legality as here in Canada.
Here it's the most important thing, not the install.....no label on the transmitter with valid certification issued by an approved test facility, whether BETS-1 or RSS-210....no use, nothing else matters. FM or AM
Mark
Here is something I am wondering about, and I am not disagreeing with anyone here. The Procaster is FCC certified and designed for use with up to 250 feet of shielded audio/power cable, and sold with either 50 ft. or 100 ft of such cable. I don't see how that cable would not radiate, yet it is FCC certified. I thought an important part of compliance was using a device as designed.
The Procaster is approved for Canada also. The certification was given with the install as designed to be used. The rule says 3 meters total antenna, ground and feedline.
Maybe there's a loophole here. Procaster has no feedline according to procaster. And the FCC and Industry Canada must agree with that and the lab in Oakville Ontario did the certification for Canada and the USA(it's on their site).
The power and audio from the indoor unit isn't considered a feedline and maybe because of the design it doesn't radiate? The design of the power/audio line may be isolated from ground or antenna besides shielded...just a guess.
But if it has the certification to be used as per instructions....no worries!
Mark
A Certified transmitter has advantages, their usally engineered to premium standards and provide the best performance. They also can help shine a positive light if inspected. But other than that, certification has no bearing on the legality of an installation, the user is always the only one responsible to insure the installation is compliant.
It's a flakey and crazy situation, and has been since 1970 when it began. In a very real sense, in order to operate any Certified 15.219 AM transmitter and be compleatly and entirely compliant with the rules; you must not connect it to anything!.. or something is going to radiate. Now the FCC came up with a solution to this back in 1976 with a proposal to simply eliminate 15.219 for manufactured xmtrs.. But they didn't, they left it alone and so this same problem has persisted to this very day.
Extended range of 15.219 had defeted it's own purpose, it was a mistake which needed to be corrected, but by the time the FCC realized this, those Certified Part 15 Transmitters had already established in a 6 year window of substantial, widespread, and growing use, and receiving high degrees of positive public response. They were mostly in Federal Parks and on the National Highways.. That FCC proposal to eliminate the 15.219 certification was not ammended, because to do so would esentially destroy the valuable and useful public resource which had been created.
Now days the Fedral Parks and Highways don't even need it anymore (though many still use it), they have the TIS created expecially for them now.
So that's why it's prudent not go about, or for that matter promote abusing the questionable liberties that 15.219 mistakenly had provided. To protect the rule; the intent/spirit of the rule must be made a priority, because to the letter can't work. As any more seasoned and knowledgable can explain here, the very maxium range that physics permits for a 3 meter, 100mw under perfect conditions is possibly a 2 mile radius (only if your real lucky).
So my attitude and advice is to use common sense and reasonableness with installation in respect to compliance, and with that aim for the best range you can get, but don't crap on the rule with obvious disregard resulting in pirate ranges.
ARRL describes enforcing part 15 as an "impossible task for the FCC to manage, and if they did, Amateur Radio might not like the line in the sand the FCC might draw with respect to signal levels. Instead, Amateur Radio gets the best of all worlds when the FCC relies on Amateur Radio to work with the Part 15 manufacturers and operators to voluntarily resolve harmful interference" http://www.arrl.org/part-15-radio-frequency-devices
That's an interesting read by the way, it's really written for hams, and covers a range of Part 15 devices, but clearly paints out a clearer picture of the part 15 situation of use and enforcement concerns.
Not sure if that answers your question, but it's my attempt.
Why is everyone freaking out about the power and audio leads now? This is literally a non-issue, feedline refers to coax or transmission line not audio or power connections.
I agree with Mighty except that I'd ad the acronym "RF" to the statement, like this:
"Feedline refers to RF coax or transmission line not audio or power connections."
I know it's not about feedlines. That's not what I said or implied, I think you misinterprit my point.. In a related thread was an isistence that an elevated ungrounded install was "legally" achieving massively incredible ranges without a ground.. But most of us here know that someting has radiating to acheive those many many miles..
The point is; If others accept that method of install as legal part 15, and it becomes a popular method of exceeding the intent of part 15, then it could plausibly incite a propsal for ammendment of the rules to combat the situtation.
It happend before.. but we got lucky, because it was voted down by the commission, which is why there are Rangemasters and Procastees on the market today.. You go abusing that luck, and you could lose it and be stuck with only 15.209
I'm just trying to illustrate that 15.219 has always been unofficially granted reasonable leeway, because to the letter is pratically impossible, so the user has some leeway, but it's important for the operator to be reasonably responsible about the install.
No one's freaking out about feedlines.
Just trying to distiquish the line between part 15 and piracy
I really don't see them adding the audio line into the rules as well. There are several reasons for this and I'll talk about this a little bit.
Assuming that your audio line is radiating RF and you go plugging that audio line-in to audio devices it's safe to say that the RF is getting into your equipment am I correct?
if the answer is yes this is an example of poor engineering practices on the manufacturers behalf which I'll explain in just a bit.
When RF in excess gets into your equipment such as a mixing board a CD player a computer whatever it is that you've got plugged into that transmitter this can cause the equipment to fail in time because of the RF that is getting into the audio line. Broadcasters and we're talking about commercial radio broadcasters has experienced this type of problem for many years and there are ways to fix that problem.
WILS in Lansing,Michigan had that problem years ago with their FM station because their sister AM station had their Tower right outside of the studio. The RF was getting into the mixing board and you could actually hear the AM station in the background when the DJ begin announcing on their FM station.
To suggest that transmitter manufacturers are deliberately allowing RF to get into your audio equipment in order to give you greater range is totally preposterous. By doing so you are claiming that the manufacturers don't care about your equipment and are making faulty transmitters just so that you can skirt around the rules a little bit.
If the RF line is radiating I assure it would be very minoot and in no way would this be intentional on the manufacturers Part. To have the RF going into the audio line as a major radiator for range would have to be done somehow on the user's Part to somehow modify the transmitter in hopes that the FCC would not catch it but by doing so they are taking a big risk on causing issues with their audio equipment. Though you might gain range by doing this you really are causing a possible potential of damaging your equipment or at the very least causing your audio to go down the toilet because of the RF feeding into your audio cable.
This is one example where following the FCC rules even if you intended to Pirate would be in your best benefit on that part because it could save you a lot of money in years to come as far as replacing your equipment.
honestly if you think honestly if you think about it correctly this is a very poor attempt to try to put the kibosh on Range. Height equals might the higher you put your transmitter the further you will get out. Why the hell do you think that commercial stations have these big huge 800 foot or 1000 foot Towers? It's not because they think it looks beautiful it's because you have to get over the objects to get more range. So this is why when you put your transmitter up higher you stand for a greater amount of range.
Other things to be considered to make things equal atmospheric conditions as well as land conditions water table conditions and speaking of water what about the water that is around you? Water conducts electricity and can often act as a sympathetic radiator. The power lines can also act as a receive antenna. This all can cause a person to naturally gain range. As was instructed by the gentleman who had the video earlier and you guys totally balked at. It is my opinion that the gentleman did not break any sort of rules he just had his transmitter up high enough and the land around him was just the right conditions that gave that person favorable range.
You know the more I read these forums I see certain people and usually the same ones always trying to diminish one's range. I don't know if it's because they are a member of some broadcast organization or what type of motivation they have but it certainly is not a motive to help the Hobby in the least.
From what I gather from Reading earlier subjects about long ground leads I from what I gather from Reading earlier subjects about long ground leads I do believe there was a gentleman who used to come on this very Forum that kept taunting the FCC about the long ground leads kept pestering manufacturers of transmitters who had displayed long ground leads to the point where the FCC finally did something about it. So it's these types of busybodies that ruin the hobby for everybody else and make it so it's a lot less fun and enjoyable.
When I saw that video it actually made me think about trying AM and somehow getting my antenna High Enough. So in a sense it made a Believer out of me and I'm not a big fan of AM. If you've ever read my post I've always been a big Pro FM type of person. So by doing this you actually helped to once again make someone in more favor of FM and actually trying to improve that rather than even experimenting with that idea on AM. So congratulations once again you've actually destroyed your own Hobby another time. Enough paranoia and rhetoric already. What's it going to take before it's too late in the hobby is totally destroyed? Have a nice day.
All Rich Powers was saying is when you can get "miles" just by getting a procaster, Rangemaster, SStran, etc. up high and having nothing connected to ground, just the 10ft antenna then something is suspect(maybe the metal tower attached to the transmitter case is inadvertantly becoming a radiator or whatever) and is worried that this is a threat to the freedom you have now.
As for feedlines, I was just commenting on Jimhenry2000's post about how can the procaster be certified with the 250 length of cable and suggested it has no feedline and the Audio/ power wires aren't mentioned in the rules and why I thought(subject to correction) that they don't radiate.
That's all.
Mark
TheLegacy, ALL commercial broadcast AM antennas are ground mounted. They also happen to be 1/4 wavelength long so they have height as well.
For Part 15 AM, height does not equal might. The best range I ever achieved (and I tried everything) was with a ground mounted Rangemaster. The reason for the range was the high ground conductivity.
It's FM where height makes a big difference, given that propogation is line of sight.
And yes, you're right. The reason for the Part 15 rules is to limit range, and thus limit interference to existing stations.
You said: "
Why the hell do you think that commercial stations have these big huge 800 foot or 1000 foot Towers? It's not because they think it looks beautiful it's because you have to get over the objects to get more range. So this is why when you put your transmitter up higher you stand for a greater amount of range."
I said: You need to invest in some research as to why AM stations use tall towers.
Thelegacy -
To expand on, and perhaps clarify, ArtisanRadio's comments a little, the main method of propagation of signals on the AM broadcast band is not line of sight, as it is with signals in the FM broadcast band. For signals under about 2MHz, the main mode of propagation is by ground wave. There is a line of sight component. I don't know how significant it is, but it's not the main method by which signals at this frequency propagate.
Regarding your comment asking why we think that commercial AM stations have such huge towers. The reason for this is that the wavelengths at those frequencies are long. For the towers (which are usually the radiating elements) to be efficient radiators, they need to be a significant fraction of a wavelength in height, so they end up being very long. This is why they are tall - not to "get over the objects to get more range". If you were broadcasting on 1600KHZ, and wanted a quarter wave vertical, it would have to be about 150 feet tall. That's pretty high. As I understand it, a lot of AM broadcast antennas are less than a quarter of a wavelength due to practical considerations, but the principle remains, that if you want an efficent radiator, it needs to be long, in terms of the wavelength.
The quality of our ground connections is very important on the AM band, and has a direct effect on the coverage area, unlike with signals in the FM broadcast band, where the propagation is line of sight.
I'd welcome input from anyone with more knowledge in this area, and am open to further clarification or correction.
Perhaps this article can help a bit -
http://www.radiomagonline.com/rf-engineering/0030/antenna-basics/26148