Also, to get a FCC visit all it takes is..."Hi Mr. FCC, I am hearing a station on 1600. A search of the database shows no records of a station in Anytown, USA. Could he be a pirate? Thanks for your time Mr. FCC, I know I am doing the right thing by helping out."
Thank you for posting John WDCX.
You are the first person to offer a glimpse of the thinking that might explain why someone would complain to the FCC about a possibly unlicensed signal.
"I know I'm doing the right thing."
I find that very interesting. I hope more points of view come along.
Rich, no one is arguing what a ground is in the realm of science.
BUT, and this a big but, the FCC used to allow grounding to masts, and they chose to interpret the words of Part 15 in such a way (and obviously, what a ground was) to allow that. That is fact, indisputable.
And with the Talking House/ATU combo, the FCC, in certifying that arrangement, obviously is not considering the coax to the ATU as a feedline (I believe it comes with 25 feet, at least, that's what I received) - again, interpretation.
The problem comes when you attempt to describe science in the fuzzy words of language, such as the Part 15 rules. At the end of the day, science doesn't change, but the words are not as exact as science.
A simple "Hobby" has evolved into a competition! Most strive to get every quarter mile that they can get! A couple blocks ain't good enough anymore!
I'm excited to send my music from my living room to my porch. That's all it's intended for. Why is that forgotten?
Give an inch, take a mile. That's good 'ol human nature. Why can't it remain simple and fun? Can't really blame the FCC. They ain't stupid! Ya swat one fly and ya kill a thousand..
All these so called "Certified" Xmtrs on the market can be made illegal very easily and they know it. They appease the buyer and give a false impression that if you use "Our" product, you'll be safe. In most cases, this is true, being the technical abilities of most of the general public but then ya got the "Gearheads" that can make a Yugo do 140 M.P.H. with a little "tweaking"..
The simple thrill of sending some music across the yard has become an obsession! There's nothing wrong with studying the physics of the hobby but there are limits and most push them to the maximum. Come back to Earth and have fun!!
Words are not as exact as science. - ArtisanRadio
I love that! It is a quotable worth quoting!
And I also enjoy the message just posted from 12vman. His view about Part 15 radio is the exact same view I have, recognizing that Part 15 AM stations are PERSONAL radio stations and they work very superbly for serving a home location.
The other dimension, that of reaching "a community," is NOT what the Part 15 rules meant to enable and frankly, I don't think the NAB or their enforcement arm the FCC want anything of the sort to exist.
In the ideal AM transmission works well at ground level, but when vacant land isn't available then elevated antennas become necessary, and the TWO reasons for adding an earth ground enter the picture. Two reasons?
Reason # 1 for grounding an elevated antenna to the earth is ELECTRICAL SAFETY;
Reason # 2 for grounding an elevated antenna to the earth is to provide the return path for efficient radiation of the AM signal.
I just thought of a way of doing it legally. WHAT? No, it's impossible. It will radiate, won't it? It will be found in violation, right?
An earth ground attachment is not in violation of the rules if it doesn't radiate. In such case it would be considered an earth ground in itself, and not a ground lead.
But the best engineering minds in the world have given up and concede that an above earth ground connection will radiate, so how could a guy called Carl Blare come up with a method of a non radiating elevated ground connection? That's the way it is sometimes. People that no one has ever heard of have brilliant brain-storm ideas, and I'm not anyone special but I've had a vision, and I'm going to share it now.
Imagine a Part 15 AM transmitter up on a 20-foot metal pole, the 3-meter antenna rising another 10-feet vertically. The ground lead of the transmitter is attached to the metal pole.
But that's just the same old thing that would be invalidated, isn't it? Well you've got to wait until I've finished what I have to say.
This metal pole reaches the surface of the earth, but it turns out to be a U-shaped pole that has a second part of itself that rises alongside the first part back up the entire 20-feet, and then dead-ends with no electrical connection to anything.
Down at earth level the very center of the curve in the U is bonded to a ground rod that is sturdy enough to support the giant 20-foot U which rises into the air. Buried ground radials circulate out just below the surface.
Can you guess why that would work?
It's because the two legs of the U would be out of phase with each other.
Safety ground, ground radials, no radiation from the pole, we win.
Hey Carl,
I admire your imagination! I am making this post in violation of my previous recommendation to terminate this thread only because you are now talking technical ways to enhance performance while being compliant with part 15.219.
There are already two common ways to eliminate ground wire radiation: (1) a vertical dipole, and (2) a precisely tuned elevated ground radial system. Your imagined U shaped ground may be a third. All of these schemes would produce a signal somewhat better than a ground-mounted vertical, but far below what you get from a simple elevated vertical with a long ground wire.
Unfortunately, all three schemes still violate the 15.219 words: "The total length of the transmission line, antenna and ground lead (if used) shall not exceed 3 meters".
You would need to "go to court" to prove the length of the transmission line and ground ground lead (if used) is irrelevent. It would be cool if somebody actually did that, but it doesn't seem likely to happen.
Carl, your imagination is great and it is true that sometimes people somewhat familiar with things can produce remarkable advances.
That being said, here's my thoughts on your proposed U tower. The current will flow downward (at an instant) through the first tower to ground and it will not return up the second tower section because it will dissipate through the earth. There will be an induced current in the second tower due to the current in the first tower but it will be in phase with the current in the first tower section (both currents going downward in this instant) so the currents will not cancel. At RF and depending upon the coupling the two tower sections are essentially in parallel. So, I don't think your idea will prevent tower radiation.
Neil
Well there's still the rest of the alphabet, I'm not stuck on a U.
Yet at the same time I am inclined to remain loyal to my huge breakthrough and get U towers in the field so we can stir up some backlash.
I'll take it to court myself if they can get me in Switzerland where I'll seek asylum.
It would be a pity if the real problem turned out to be "tower rollover" caused by the rounded bottom, with towers suddenly tipping over.
Another related idea is that of putting ground radials in the air, and previous posts have talked about this approach as being perfectly doable by installing 62-telephone poles in a circle around the outer boundaries of the property.
BACK FOR EDITORS ADDENDUM
PhilB up above mentioned the elevated radial concept but expressed a belief the F-double-C would disallow it because the ground lead would exceed the length, but I would think that ground radials, which would induce phase-canceling, would not be ground-leads but actual ground. I'd do it.
The other idea, the dipole approach, would place the transmitter in the middle, with a 5-foot wire going straight up and a 5-foot wire going straight down, for a total of 10-feet (3-meters). I don't see why this would be questionable. It's just probably true that a 3-meter vertical at the ground with buried radials would perform better.
Member Blare posted: ...His view about Part 15 radio is the exact same view I have, recognizing that Part 15 AM stations are PERSONAL radio stations and they work very superbly for serving a home location.
The other dimension, that of reaching "a community," is NOT what the Part 15 rules meant to enable and frankly, I don't think the NAB or their enforcement arm the FCC want anything of the sort to exist.
In the ideal AM transmission works well at ground level, but when vacant land isn't available then elevated antennas become necessary, and the TWO reasons for adding an earth ground enter the picture. <snip>
Hasn't experience shown that a 3-m (or less) length of wire attached to the r-f output connector of a MW transmitter using 100 mW dc input power (or less) will radiate a strong enough signal to serve AM radios at a single "home location?"
If the operator's "coverage" goal is limited to his own home location, probably there is no need to find vacant land for an outdoor antenna+buried radials, or to use an elevated mount where FCC §15.219(b) and the National Electrical Code conflict with each other.
To Mr. Rich's recent post...
"If the operator's "coverage" goal is limited to his own home location, probably there is no need to find vacant land for an outdoor antenna+buried radials, or to use an elevated mount where FCC §15.219(b) and the National Electrical Code conflict with each other."
... I agree.
The thought also brings to attention a possible contradiction in the way some tend to view Part 15 AM radio, a contradiction which I myself have exhibited.
Yet I am not so conflicted as it may appear; time for a little self-psychology.
I tend to be sympathetic toward all interest in Part 15 AM, even toward those who hope to cover enough ground to build an audience, even though that is not my ambition. But it explains why I entertain the larger way of viewing Part 15 life.
This double-sided viwpoint also explains why I have active projects in both areas: the Indoor Antenna Project, and the newly announced Outdoor Antenna Building Project. What will these projects hope to demonstrate?
The indoor antenna hopes to find minimal antenna arrangements that provide useful coverage of home and yard, whereas the outdoor version expects to show the maximum of what's legally possible.
It is reasonable to allow that different Part 15 minds will not all see the world in exactly the same way.
i use a TH5.0 and it's companion ATU. the ATU is UNGROUNDED. only ground it gets is via the TH unit and AC power supply it was certified with
the atu is suspended from the ceiling horizontally on a second story balcony in a apartment setting.
i get a listenable signal to a car radio out to about a 1/4 mile to my grundig portable about 1000ft to a JVC boombox about 50 ft (if even that far) from building. no building penetration except for the building where tx is located and only partially to the two adjacent buildings.
in the car radio if i roll up windows turn up volume on radio i can barely copy my signal under all the static on car radio just enough that i can make it out as my station out to about two miles but it's very sporadic and unlistenable even to me and it's not consistant. my consistant listenable range is what i stated above about 1/4 mile max to a car radio.
given that range in my neutered situation i would like to see what it would do over a full ground plane and ground mounted.
i am operating in what i believe to be (good faith effort to remain legal) within the certification parameters of the TH unit with it's companion ATU using all presently available information as a guide mainly in this case the fact it was certified and the user manual that is supplied with it.
Radio systems has a 35 year good reputation in the low power field and these were sold by the 1000's over the last 15 or so years before radio systems bought out the company with only two known citations in those 15 years both situations under suspect circumstances involving other concurrent or previous illegal activity.
should i ever get visited i will most certainly make a detailed account on the visit and what the outcome was and the why for the outcome.
will be polite to the agent but will ask a lot of questions that we need answered to here on the forums. i wish i had an FCC contact i could discuss all these issues with that we discuss here.
I'm not sure what the intention of Part 15 (or RSS210/BETS as it is known in Canada) radio was originally. I doubt anyone posting here really knows either.
But the fact of the matter is that the opportunity does exist to broadcast legally and without a license. That opportunity allows radio to exist either in a home, or in a small geographic area which might not be served otherwise.
Ken Norris's Friday Harbour station, my station on Bowen Island and, I'm sure, many others, demonstrate that Part 15 radio can serve a community. I also believe that realistically it has to be in conjunction with Internet streaming. But it can serve others as well as just yourself. If you don't want to, you don't have to.
I don't believe that there is any gain going outside the rules. You're not serving the community if you're breaking the law. But there's nothing wrong with pushing against the boundaries, as long as you remain within them.
And as I stated previously, the rules, as mere words, are inexact and subject to interpretation (as opposed to the science, which, outside of Quantum Physics, is exact).
So whatever the FCC/Industry Canada inspectors say is legal, in my opinion, is legal. If you're not now allowed to ground against a metal mast in an elevated installation in the U.S., then that is breaking the rules. In Canada, they take a more relaxed viewpoint on grounding, particularly when safety is involved, and here, those are the rules (even though the wording in our rules is almost exactly that of the U.S.).
I certainly support the technical holy grail quest of maximizing range legally. And I also think we don't don't need to stress about it.
OK everybody, take a deep breath and go OMMMMMMMM.
AR everytime there is an AM NOUO we go round and round on this same subject with the same outcome. the same cast of characters spew the exact same wording almost verbatim.
i personally have become desensitized to these am nouo's.
As this thread grew I began to think and learn things that wouldn't have come to me had it not been for this thread.
I believe everyone's contribution played a part, and there are even things I'd say differently if we could retrospectively change it.
But, as the guy says, the subject will come up again, and we know our lines.
are you saying that the antenna and the ground should be a ground level ? 3 meters is not high enough for a good signal...is that the whole purpose ? Nash