I was not able to access your link to the Rangemaster manual, RichPowers, but the manual and the quick setup instructions are on the website, and can be downloaded by anybody. I don't see the detailed instructions and illustration showing how to make a long ground lead installation, that were there before. It seems to me that Rangemaster has definitely toned down its promotion of long geound leads, at least on their website. There were also photos of Rangemaster installations on tall towers in previous versions of the website. The tower photos are all gone, also.
As for what to do when installing your transmitter, you're on your own. The certification will not prevent an NOUO, as has been demonstrated several times. As Keith Hamilton and his associates have pointed out, some FCC agents have accepted installations with long ground leads. Others have not, however. For those who received NOUOs, it has sometimes been insinuated by the manufacturer that they had done something wrong that was not stated (like maybe pissing off the agent?), and those not doing something else wrong will be OK. These matters are kept very vague, and no details are given.
.. do your best while you try to get the best signal.
Yep, Yeah, I know.. I just got bent out of shape on it for a moment there. Such a frustrating tiptoe of a dance, easy to stub your toe, and I put out a holler.
It'll all work in the end.
.. the manual and the quick setup instructions are on the website, and can be downloaded by anybody. I don't see the detailed instructions and illustration showing how to make a long ground lead
It's there, Page 6 of the Full Manual. (That link posted above is directly to the pdf - works fine for me)
But, it also clearly states:
Elevated radials
First of all be aware that elevated radials do increase
radiation, and may not be approved should you be
inspected by the FCC
The "Full Manual" that can be downloaded from the Rangemaster home page is not the same as the one described by RichPowers. Page 6 of the home page "Full Manual" merely has a PC board view that shows the location of some components. None of the text of the home page Full Manual contains what RichPowers says.
The link provided by RichPowers for his Full Manual is blocked by some security feature. I wonder if other people are also blocked from accessing the link.
It looks like there is a difference between the Full Manual that can be accessed by the general public (and the FCC), and the one that can be accessed by Rangemaster customers.
What it appears like is that Rangemaster has cleaned up the portions of their web site that can be accessed by the FCC in order to avoid trouble with them, but provides secret information for their customers.
This is something like a spy novel. Is the father of the cute little blonde girl holding the Rangemaster really so devious? Plese show me that I am wrong.
Note: Just because the transmitter and/or components are certified does not mean an installation is certified.
The rule is relatively simple:
Section 15.219 Operation in the band 510 - 1705 kHz.
(a) The total input power to the final radio frequency stage (exclusive of filament or heater power) shall not exceed 100 milliwatts.
(b) The total length of the transmission line, antenna and ground lead (if used) shall not exceed 3
meters.
The argument is: What constitutes a ground lead?
Some say it's just the short wire between the TX ground terminal and Earth ground. Others say it's the short wire connecting the TX ground terminal and any metal frame, pole, water pipe, or what have you, which eventually connects to Earth ground.
However, if it is a long vertical wire, then it effectively becomes part of what could be called a dipole antenna, i.e., the long ground wire radiates beyond the definition of unintentional radiator, and thus becomes part of the radiating antenna, the entire length of which cannot exceed 3m.
Section 15.209 Radiated emission limits, general requirements.
(a) Except as provided elsewhere in this Subpart, the emissions from an intentional radiator shall not exceed the field strength levels specified in the following table: **(NOTE: I isolated the band we're talking about here)**
Frequency Field Strength Measurement Distance
(MHz) (microvolts/meter) (meters)
_______________________________________________________________
0.490 - 1.705 24000/F(kHz) 30
In the case at KENC, the tower, like a long vertical wire, was probably radiating more than the antenna (the supposed intentional radiator), and the whole system was radiating many times more field strength than allowed by .209.
IIRC, both rules were invoked in the NOUO, plus, oddly, the fact that the ground connection was not shielded was also mentioned.
I haven't investigated the Procaster, but the Talking House external ATU was certified because, since the tuner is part of it and it bypasses the transmitter's internal wire tuner, it apparently stands muster ... i.e., the coax cable core wire is not considered as transmission line, nor its shield as ground lead.
What would happen if the Rangemaster could be mounted on the roof directly above the building's main ground post? Could Rich run a heavy ground wire through a conduit weather head straight down and clamp it to the same ground post?
The "Full Manual" that can be downloaded from the Rangemaster home page is not the same as the one described by RichPowers. Page 6 of the home page "Full Manual" merely has a PC board view that shows the location of some components. None of the text of the home page Full Manual contains what RichPowers says.
No no no no no Ermi, that's not correct, it is the same manual, I'm not sure where the confusion is coming in..
From the downloads page at:
http://www.am1000rangemaster.com/downloads.html , {accessible from the homepage by clicking "downloads)
then, at the top, under "Installation Instructions", it says "Download full manual here (New Manual)"
--And it's on Page 6, -2.3 Using Ground Radials
I'm not accessing some special link or anything.
No mysterious stuff!!
The Rangemaster AM-1000 ground circuit must be understood to understand the dilemma this device presents in its installation and use. Let me precede my analysis with this; the FCC inspection results over the past couple of years were promulgated on the premise that the operations were thought to have exceeded the signal limits of the Part 15 rules. Regardless of how the enforcement action was executed by the Commission, the facts remain to support the inspectors "opinion" of the violation. To my knowledge, no one has ever questioned the results of a Part 15 inspection report and provided the FCC with independent data supporting the local operation as in compliance on all counts.
Now to the actual transmitter ground circuit. A short trip through the circuit board, transmitter and associated equipment with an Ohm meter shows that all the grounds in the device are connected together. This would include the pole mounting bars for mounting the transmitter. This would mean, regardless of having a down-lead conductor, the transmitter metal-pole mounted above the earth would cause the pole/mast to radiate.
Additionally, for the audio pair it is recommended to use shielded cabling. One could conclude by this design that the grounded shield conductor would also radiate. Plus, without some inductive reactance introduced in the DC power leads, one side of the DC power input is common with ground causing it to radiate as well.
The audio and power cable radiation can be solved simply with several ferrite beads on the wires.
The mounting to the pole is a much more complicated concern. The transmitter MUST be grounded for lightning and static discharge protection. Even if the pole were only 4-5 feet above ground level, the pole will radiate. To complicate matters, buried ground radials of any length, will increase radiation from the system.
Now to clearly identify the REAL issue. When bringing 15.209 and 15.219 into play, design does not become a factor in the FCC inspection actions. All else being equal, the outcomes begin with signal strength and migrate to the 3-meter length issue. If we look at the issues as an inspector, how do you do your job? What is the process of inspecting a Part 15 station operation? There are only two parameters that will cause a finding by the inspector (who can only recommend action). The only violation I have noticed to be prosecuted by the inspectors is a Notice Of Unlicensed Operation (NOUO) of a Part 15 broadcast station due to excessive signal strength.
Frankly, inspectors don't care what you mount the transmitter on. They are looking at 15.209 first, and then 15.219. If the field strength is more than provided for in 15.209, then the inspector goes to 15.219. That is because engineering practice and theory would suggest the first place to look for increased signal would be increased length under 15.219. So, in the final analysis, what matters most. The answer: field signal strength. Taking a look at the KENC situation, that is exactly what happened on each and every KENC transmitter (3).
If you pole mount a Rangemaster AM-1000 and exceed the signal strength standard, someone complains or you get noticed in a publication, or the inspector notices your signal on a local frequency sweep just out of curiosity, you might expect a visit.
Pole mounting, short pipe ground mounting, extensive ground radial systems, mounting on a metal building, transmitter design, construction and installation, certification, don't matter at all if the inspector finds too much field strength and believes the operation of the device has the potential of causing harmful interference.
I have learned to simplify my life and not worry about the "stuff" of life. I work on what I can change and accept what I can't. The three most important words in the English language, "Get over it". Life is full of confusing situations and outcomes. Most of the time, trying to make sense of what you cannot change creates an outcome that creates greater confusion. Personally, I need to go away now and take my own advice.
Thanks for the insightful post Marshall,
But:
If the field strength is more than provided for in 15.209, then the inspector goes to 15.219. That is because engineering practice and theory would suggest the first place to look for increased signal would be increased length under 15.219. So, in the final analysis, what matters most. The answer: field signal strength.
I'm a bit confused here. I thought that with a transmitter certified under 15.219, then the compliance factor would fall specifically under 15.219..
What I mean, is that I thought it was an either/or situation.. requirement being either you have to comply with .209 OR .219, and not both..
My understanding is that the Rangemaster/Procaster/I.AM certifications under 15.219 is the very thing providing the allowance and advantage of extended range?.. thus as much as 1 or 2 miles, and not 200ft.
Yes, I found the new manual under "downloads." Thanks, Rich! I'm glad that this is not a scenario written by Tom Clancy. The confusion resulted from the fact that there is another link to the "full manual" on the Rangemaster home page that leads to a completely different manual.
The link I first looked at is in the extensive text on the home page. This can be found by first scrolling down to "Why buy a RangeMaster?" Just below the pictures of the meters, there is a paragraph that starts with "Are you a church?" On the next line, there is the link "Download full manual here." Clicking on this link leads to another, older, manual.
I notice that in the new manual, the ground lead is now called by another name, "ground radial." I suppose that Keith Hamilton has had enough of the term, "ground lead." The fact is that you really need a long radiating ground lead (or "ground radial," or pole, or tower) to get the "1-2 mile range" that is advertised. It's no wonder that Rangemaster will not give up on the radiating ground lead very easily.
Ground radials that are covered by soil do not radiate much, but they can improve signal strength considerably by reducing the ohmic loss resistance in the ground circuit of the antenna.
As far as I know, nobody has received an NOUO for ground radials, but it would not be too much of a stretch for the radials to be considered to be part of the "ground lead" under Section 15.219(b).
As kk7cw pointed out, the real violation is making your Part 15 AM installation too good. The inspectors carry field strength meters to enforce a section of the Rules where the maximum field stength is not specified. I wonder what maximum field strength they have in mind before they start digging further. Maybe 10,000 uV/m at 30 meters? 5,000? It would be really good to know. Freedom of information requests of that nature have been denied lately.
How many Ramsey, SSTRAN, Rangemaster, ProCaster, Talking House, Vectronics, Spitfire/Gizmo, home brew and other AM transmitters are in the wild today?
Likely thousands, in total.
This research:
http://lowpowerradio.blogspot.com/2011/01/fcc-enforcement-actions.html
found 21 NOUOs for enforcement actions in the AM band in 8 years
21 in 8 years and of those 21, 14 were for simply ridiculous power levels - thousands of uV/M, often from farther than at 3 Meters
So that leaves 7 NOUOs in 8 years for 3 meter violations and one had a 100' ground line, so that's 6 NOUOs in 8 years for three Meter violations
And one of those is KENC - so that leaves five
Fewer than one per year, AND no fines, no confiscations, no imprisonments - just NOUOs
No FOIA required, all you gotta do is read the field notices.
Does fewer than one NOUO per year with thousands of transmitters in use really merit this kind stress?
SCWIS is dead on target with his advice. Chill out.
Rich Powers, please understand you're trying to apply a constant standard of enforcement of Part 15 rules by all FCC inspectors. This approach is unwise and leads to further confusion. The Enforcement log gives the impression that it's one or the other of 15.209 or 15.219. Actually, in some cases both sections can be brought to bear for the reasons previously posted.
I believe it was Don Quixote who was confused and began tilting at windmills. This resulted in folks thinking he was mentally dispatched. Before we re-bury the dead horse, everybody take a good look. Then lets hold a well deserved funeral for the 15.209 and 15.219 dead horse. It's written in English on purpose and requires no interpretation. I'm just sayin'...
Scwis I've glanced that list before, but just now took the time to actually read the first dozen or so of them.. I'm think I might print them out later, and do the best I can with the info.
Marshall, How appropriate your comparison!
I believe it was Don Quixote who was confused and began tilting at windmills.
It inspired me to create a little cartoon..
The cartoon is hilarious and your avatars are delightful.
Rich Powers:
Your hilareous cartoon has me tilting with laughter!
Rich...you have done it again...LOL.