Says a range of 1 to 2 miles is possible. They never claim what some have as 5 to 6 miles.
Background noise for Part 15 devices was mostly non-existent then.
http://transition.fcc.gov/eb/FieldNotices/2003/DOC-329959A1.html
would anyone like to talk about radials now >>??<<
I still believe hoist that transmitter to the tallest tower and hook an audio line and a power line and use about 60 rf chokes to demonstrate your not trying to allow your cable to radiate
JOE THE RADIO DOOD
***************************************************** NOTICE ************************************************** This document was converted from Microsoft Word. Content from the original version of the document such as headers, footers, footnotes, endnotes, graphics, and page numbers will not show up in this text version. All text attributes such as bold, italic, underlining, etc. from the original document will not show up in this text version. Features of the original document layout such as columns, tables, line and letter spacing, pagination, and margins will not be preserved in the text version. If you need the complete document, download the Microsoft Word or Adobe Acrobat version. ************************************************************** FEDERAL COMMUNICATIONS COMMISSION ENFORCEMENT BUREAU Northeast Region Detroit Office 24897 Hathaway St. Farmington Hills, MI 48335-1552 October 9, 2014 (Sent via Certified Return Receipt Requested and First Class U.S. Mail) Steven Cherry Hamtramck, Michigan NOTICE OF UNLICENSED OPERATION Case Number: EB-FIELDNER-14-00013074 Document Number: W201532360001 The Detroit Office received information that an unlicensed broadcast radio station on 1610 kHz was allegedly operating in Hamtramck, Michigan. October 1, 2014, agents from this office confirmed by direction finding techniques that radio signals on frequency 1610 kHz were emanating from your residence in Hamtramck, Michigan. The Commission's records show that no license was issued for operation of a broadcast station on 1610 kHz at this location in Hamtramck, Michigan. Radio stations must be licensed by the FCC pursuant to 47 U.S.C. S 301. The only exception to this licensing requirement is for certain transmitters using or operating at a power level or mode of operation that complies with the standards established in Part 15 of the Commission's rules, 47 C.F.R. SS 15.1 et seq. The field strength of the signal on frequency 1610 kHz was measured at 30,000 microvolts per meter (uV/m) at 40.7 meters, which exceeded the maximum permitted level of 14.9 uV/m (24000/1610) at 30 meters established in Section 15.209(a) of the Rules (See 47 C.F.R. S 15.209(a)). Thus, this station is operating in violation of 47 U.S.C. S 301. Another exception for some transmitters operating in the 510 kHz to 1705 kHz band is found in 47 C.F.R. S 15.219. Specifically, Section 15.219(b) of the Rules states "the total length of the transmission line, antenna and ground lead (if used) shall not exceed 3 meters" (see 47 C.F.R. S 15.219(b)). The investigation by this office determined that the ground lead itself was longer than 3 meters, thereby, increasing the total length of the transmission line, antenna, and ground lead well beyond 3 meters. This installation violated Section 15.219(b) of the Rules. You are hereby warned that operation of radio transmitting equipment without a valid radio station authorization constitutes a violation of the Federal laws cited above and could subject the operator to severe penalties, including, but not limited to, substantial monetary fines, in rem arrest action against the offending radio equipment, and criminal sanctions including imprisonment. (see 47 U.S.C. SS 401, 501, 503 and 510). UNLICENSED OPERATION OF THIS RADIO STATIONS MUST BE DISCONTINUED IMMEDIATELY. You have ten (10) days from the date of this notice to respond with any evidence that you have authority to operate granted by the FCC. Your response should be sent to the address in the letterhead and reference the listed case and document number. Under the Privacy Act of 1974, 5 U.S.C. S 552a(e)(3), we are informing you that the Commission's staff will use all relevant material information before it to determine what, if any, enforcement action is required to ensure your compliance with FCC Rules. This will include any information that you disclose in your reply. You may contact this office if you have any questions. James A. Bridgewater District Director Detroit Office Attachments: Excerpts from the Communications Act of 1934, As Amended Enforcement Bureau, "Inspection Fact Sheet", March 2005
That's very similar to other AM citations, nothing odd about it. I can only make an assumption since the deatails are vague, but I get no impression at all that it is making reference to the use of ground radials - I think it's logical to conclude that it is an elevated system with a long ground wire running down to the earth
Case in point, TIS systems also are limited by a total legnth requirement, but ground radials are optional (though advised), and not considered as part of the total length of the system.
The reason that the FCC limits the length of antenna systems (including ground lead) is to limit field strength and therefore range, which limits interference.
I don't think that you're going to be able get away with claiming 5 miles of range, while at the same time also claiming you're legal. The maximum theoretical and practical range (from experience) of a legal (ground-mounted is the only way to be sure) Part 15 AM transmitter is 1-2 miles to a sensitive (likely, car) radio. And that's for an excellent installation, with either radials or great soil conductivity. You'll also likely get less range to cheaper, deafer, portable radios.
If you have an elevated install, you can never be sure that something else other than your 3 meter antenna isn't radiating. If you're getting much more than that 1-2 mile range, then you can be pretty sure that something else IS radiating.
Pretty simple, actually.
I keep trying to think of ways that station operators could declare such large distances as we have sometimes heard and I thought of another way.
Measuring the diameter of the circle from edge to edge might add up to 3 or 4 miles!
Of course the transmitter is in the center of the circle therefore the measure from the antenna to the outer edge would be 1/2 of the diameter of the entire circle.
In a circle of this size there are many many square feet! What huge number would that be?
he was running a 40 foot tower
with a ground wire from Hamilton
Straight down to ground so about 40ft
ground wire to a ground rod not a radial field etc
ken said his average was 4-5 Miles
now he's doing lpfm and quit am
But he believes he was able get out
so Good by his forty ft ground wire
And being 40 ft in air ...
joe the radio dood
1680 am KOIW
radiokoiw..com
Carl, One of the reviews I just read on the Procaster web site, the user claimed exactly that, his range claim was double the distance he went to one point of reception.
The 40ft water tower was only the most extreme violation of KENC, he actually had 3 (or was it 4?) Rangemasters spread throughout the town all broadcastinging at the same time.. another was on the roof of the football stadium, and another somewhere else - there's nothing questionable about doing that, except that everyone of those transmitters involved extreamly long grounds.
As for to your previous comment: "anything other than 3 meters is cited"
"The 3-meter combined length specified in Section 15.219(b) refers to the length of all radiating elements"
The role of "ground" becomes even more awesome when we consider the several ways of having "virtual ground" by ignoring the earth and putting it up in the air.
Two ways exist of raising the "ground" up above the ground.
Elevated radials work and are legal, as we've discussed... legal because if done according to good engineering do not radiate;
The negative half of a dipole antenna establishes a virtual "ground in the air" as no further earth attachnment is required except for lightning safety. Problem is with only 3-meters to work with a dipole antenna in the medium wave band would be no more effective than a 3-meter antenna with no ground at all.
No matter how RF ground is achieved, the 3-meter limitation dooms the results.
"15.219(b)). The investigation by this office determined that the ground lead *itself* was longer than 3 meters..."
So on a site built to meet Motorola R56, with the shelter on top of the tower*, with the grounding lead between the transmitter and the common ground bar being shorter than 3 meters that's OK?
SP
*A steel fire watch tower.
I see your point spareparts.
This may be one of those cases where the FCC's own language in their NOV or NOUO does not literally match the wording of the part 15 rules.
It has happened before and always leaves us in a swirl of uncertainty.
Dealing in such small measurements... 3-meters broken up into several parts... I often wonder if the FCC takes it so seriously.
It is likely that they have "room for error" in the way they measure the small bits, and maybe can "adjust" their judgement based on whether they "approve of" the operator and his station.
SP wrote in Reply 27: .. So on a site built to meet Motorola R56, with the shelter on top of the tower*, with the grounding lead between the transmitter and the common ground bar being shorter than 3 meters that's OK?
*A steel fire watch tower.
The issue here is that an RF ground does not, and cannot exist at the top of a conductor or other metallic structure that extends above the surface of the earth -- even though the base of that conducting structure is buried in the earth, and/or bonded to an elaborate network of buried radial wires or cold water pipes or ground rods.
Therefore connecting a short wire defined as a "ground lead" from an elevated transmitter to the top of those conductors does _not_ provide an r-f ground for the transmit system.
In reality, that short wire PLUS the length of the conductor it connects to all become part of the radiating length with whatever conductor is attached to the antenna output connector of the transmitter.
With apologies to the many readers who have seen this before, below is a simple illustration showing the basics of this type of installation.
The ~ vertical red lines there show the total length/height of the setup that is a radiating part of the antenna system.
I accept your apology.