That is definitely not Part 15 legal. No configuration with that antenna at 15 feet is going to get you a legal field strength. The average Part 15 FM will at most push 1,000 or so feet to a car radio, though typical compliant range is a few hundered feet. 1 mile is 5,500 feet a 1/2 mille is 2,750 feet. Dial back the coverage until it fitters out about 1/2 mile out consistantly on your best radio. At this point you appear to be at minimum 5x the allowed field strength.
(Edit: Do Note even a 1/2 mile of FM coverage is questionable from a legal standpoint, ballpark is 300-600 feet of coverage for compliant operation.)
I had similiar coverage to you on FM with a similar setup and was visited by the FCC for illegal operation. The station was found to be in violation and exceeded the legal field strength limit.
Get your bad news here.
Not sure for the US(well, more likely than not), but here in Canada the radiating antenna has to be attached to the transmitter.....not remotely located via coaxial cable. Still would like to know what transmitter you are using? If it's part 15 compliant, taking into consideration the losses through the cable up to a mile range even to a car radio doesn't seem likely.
Mark
IIRC a part 15 transmitter cannot be certified and have a common antenna connection. Though there have been exceptions to this rule, most notably the Rangemaster and Talking House transmitters.
I get about 1/4 mile in some directions with a Sosche FM transmitter ($10 from wal-mart) and about 29 inches of wire on the negative battery spring and about a 2 foot headphone extension cable.
I power the transmitter with 2 sets of 3 AA batteries in parallel giving it 3.6 volts and it will run unattend about 4 days. The whole shebang is mounted outside about 8 feet off the ground.
Here is a link to a thread I started about the project, I will try to update the info soon
http://www.part15.us/forum/part15-forums/general-discussion/my-summer-microbroadcasting-project
Not bad for modifiying a $10 sosche transmitter. Seemed to have missed the first post about the sosche transmitter.
Legal, I don't know but amazing yes. If you get a mile, or even half a mile, you probably are over.
ANY transmitter used here in Canada has to be certified by Industry Canada with number on the label, and unmodified.
But if I could get away with it I would just do what you did with a $10 one like yours.
Mark
An FCC Certified FM Part 15 transmitter is required to have an attached antenna, which is part of the certification. It is required to be conected with a "non-standard" connector, or even affixed in a permanent manner to prevent a user from easily changing it. If a transmitter has, say a typical BNC or type F connector, it's not legally certified.
However, it could still be legal. There's a difference between legal and certified, and being certified does NOT guarantee that you have a legal transmitter. But if it's legal, it's legal. Basically, for FM, legal means no more than 250 u/Vm at 3 meters. There is no discussion to be had about that. If you're 255 u/Vm at 3 meters, you're not legal. If you're 1500 u/Vm at 3 meters you're not legal. Etc. This field strength measurement is the ONLY standard by which Part 15 FM transmitters are determined to be legal.
I wish I was retired and rich, so I could simply hop around the country to Part 15 FM stations that insist they're legal but have never seen a field strength meter, and take some readings and show them what they've got. Based on physics, and my own open field tests last year it's simply not possible to get a half mile, much less a mile, with a maximum of 250 u/Vm at 3 meters. If you use better antennas for better range, you're getting that range because the more effecient antenna is putting more signal into the air, which means increased field strength.
TIB
Carl, a good version of a the town crier, you gave me a laugh in an otherwise tumbling thread, seeing someone alive with the sound of music on their new station and to cast doubt and not support.. It's un-American, we don't have Gestapo here, secret police on every corner, and I'd rather trust what my neighbor says and not have the mindset to suspect them.
I'll never come down on someone's operation because a wire to ground is thought to be too long, or range is supposedly too much. How do we know they're not bragging, or have estimated the distances wrong? If they say it's good, it's good, I'm not at their house to see it, or listening to the radio there, I feel I have no right.
Fury Radio Network though, ha, weren't those the guys who hacked the radio station in Denver CO and aired hours of mascot sex ramblings? It was reported right here on Part15 (us)! Now you'd better stop that stuff right now, oh!
I didn't realize it was considered un-American to help your neighbors. Heaven forbid we actually talk about legal part 15 on this site.
That is why this site exists.
There is so much misinformation 'out there' about Part 15 operation, particularly FM, and a lot of it is perpetuated by other sites, including Facebook. It's difficult to know what the true facts are, and often FM and AM get jumbled together (I can't count the number of times I've read about how the legal limit for FM is 100 milliwatts).
Thanks to Mighty1650, TiminBovey and a few others who talked about the rules, physics, and more specifically what it means in terms of range, to broadcast on the FM band legally under Part 15. If I were unintentionally breaking the rules, I would appreciate others with more experience letting me know. And it has nothing to do with being a whistle blower or town crier.
Another thing I've noticed is how every few days a newbie arrives to report on all the rules he's breaking on FM and declares he wants to operate within the rules.
All over again an attempt is made to explain what the part 15 FM rules actually say, and most of these newbies fade away and others arrive.
None of these newbies EVER show the slightest sign of having read the rules for themselves.
Ok, so I actually have read the rules and reread them to make sure I am somewhat familiar. I don't like rules, but I, being the good sheeple I am, conform to them. I never have aclimated to the idea of being wrong, so I do my best to not be.
Right, now I heard 3 seconds of dead air on my station. I am tempted to drive over and correct the cue points on the songs that were playing. OCD I am at times.
BTW, I see the same thing on the motorcyle boards I hang out on. The same questions over and over.
The one thing I can say, is that you will occasionally catch a new member that will stick around for a while, however most will not. Teaching is continuous and even monotonous, learning is up the audience (I made that up). And in the case of Part 15 AM or FM, wouldn't matter if the power levels were infinately higher or not. There is always an excuse not to continue for those that are just a "passing fancy."
I wrote this rambling post without the aid of alcohol tonight. I think I will go to bed... Heat is getting to me!
Oh, and if it matters, Thanks to everyone that has comments and answers to the same questions over and over. Some of us appreciate it! I learned a lot on this site, let me say that again, this site. I searched and read the archives for hours to see what worked and didn't for this new to me venture into micropower A.M.
Thanks I needed that, craigf, a reminder that generalizations are never true... and I did generalize by batching all FM newbies into the same illiterate bunch.
Of course there are the eventual loyalists who find a comfortable home on the website and become one of the teachers who join the repetitive lesson giving.
As far as alcohol is concerned I discover that my typographical errors remain high with or without booze, so I am forced to blame the Belkin keyboard as being spell challenged.
Admittedly I still have faith that somewhere in the rules are hidden rewards just as Bible people are certain that enlightenment is waiting to be found in the right chapter and verse.
Revolving red light! Pull this station over to the side of the dial!
Okay lets be realistic here, some of us talk a good talk, and so is the case elsewhere, but I truely do not think everyone is 100% legal, as in real legal.
I think there are those who preach the rules, but do not 100% follow them themselves.
I pick up tide-bits here and there in people's language that leads me to believe that a few who preach the rules do not follow their own advice.
It is okay to warn people who appear to be operating above the absolute legal limits, but let's not shun those that word their words to raise our suspicions a bit that they might be intentional law breakers.
Now I am not calling anyone here out directly on my claims that you are the law breakers, but I see some here that are questionable.
True, those who do break the rules, ruin it for the rest of us, who abid by the rules whether we like it or not, but shuning people who do, is not the best idea. They can still learn to operate legally if they are allowed to hang out with the legal crowd and learn new things.
Perhaps, they can operate in their area without a visit, could be no interference is produced by their semi-legal..semi-illegal station and the FCC feels they have bigger fish to fry.
Granted, if he answers your questions about his equipment, he'll get some slack from the crew here, but lets not be like that other site, where only its owner's best buddies can break the rules but not outsiders to the "kiss my big fat butt" fan club.
Bruce.