Questions About Using FM With Christmas Display

Hi, Nick,

You are welcome to join the forum and post as you wish.

Regarding the license free use of a transmitter on the FM broadcast band, such operation in the US is governed by Part 15. 239 of the FCC rules.  There is no power restriction but there is a field strength restriction which effectively limits your expected range to about 200 feet.  Usually this can be adjusted by changing the length of the transmitter antenna.  This is what I do at my "station".

Try to select a frequency which is not in use or next to a used frequency in your area.  Go to this site: https://radio-locator.com/ and click on "vacant frequencies".  You might find this is helpful in selecting your frequency but always check to make sure it is vacant.

Neil

Basically the C-Crane FM2 is about all you'll be allowed under part 15.

Its a little under the max limit but as Timinbovey tested the Whole House FM Transmitter 3.0 though certified went well above the max limit of 250 uVm @ 3 meters.

You can expect about 75 Ft from your house as reported on most Radio's these days.

Better off to go AM under part 15 section 219 you get more legal range because your allowed 100 Milliwatts with an antenna at 3 meters in length.

Since your NEW even though the Talking House AM transmitter is NOT my favorite you can get one for $95 brand new @  http://www.talkinghouse.com/ and out of the box with the wire antenna you can get 500-1000 Ft.  But there is a new ATU comming out that will make it go further.  The music is listenable but sort of sounds like someone talking with their nose plugged.  (Horrible audio) but I suggest you save your pennies and get the improved iAM transmitter that will blow away the audio quality of the talking house.  The iAM costs $189.95 (You do get what you pay for) and it sounds 200-400% better.  Its like comparing a Fisher Price toy stereo to a Macintosh high end stereo system.

If you can afford it the Procaster is the easiest but it seems to me your just doing it for a light show so iAM is the safest bet.

Find an AM frequency usually from 1620-1700 that is blank daytime and as quiet as possible at night.  You'll probably be safeer on AM than FM as the FCCC does not take any transmitter like those Chinese transmitters you see on eBay or Amazon such as those advertising 1/2 mile or greater range lightly on FM.  and you (not might WILL get a serious visit from federal agents from the FCC with a written letter called a NOUO or worse).  so if you DO go FM make sure its a legal CERTIFIED FM transmitter (Decade MS-100, C. Crane FM2, Broadcast Vision) and your OK but just don't expect any REAL range on legal FM under part 15.  I got a ticket so I know all too well about that one.

AM you can under the right conditions LEGALLY go 1.5-2 miles and won't get any sort of ticket so long as you don't jam a used frequency.

Good Luck let us know what you'll do.

How to Be Legal with FM

It takes a bit of electronic know-how, but if the certified FM transmitter/antenna is located on a mailbox pole, flagpole, or other vertical pole close to the street, then drivers-by will receive a strong signal on FM without risking a rule violation.

I'll throw in another idea I have...

On a post mounted right at the street, mount a large red pot festooned with a wreath, and on your station make an announcement as follows:

"Help support your curbside Christmas station by dropping a free will donation into the pot to bring this great Christmas Light and Music Show to your friends and neighbors. And Happy New Year!"

To simplify things, you have (legally) a choice of using either AM or FM FCC Part 15 compliant transmitters.  I'd recommend that if this is a new venture for you, you purchase an FCC certified transmitter.  These devices have been tested in labs authorized by the FCC and theoretically they transmit within the limits allowed by the FCC.  You may not get caught if you use an illegal transmitter (readily available on e-bay or Amazon, ironically), but then again you may, and it's a bad time to get caught right now - the FCC has an ongoing initiative right now to crack down on pirate radio.

You'll get better quality sound with FM, but far less range.  Expect less than 200 feet to typical portable radios (i.e., a couple of houses on either side of you) and slightly more for those listening on car radios (your range is dependent, among other things, on the quality of the radio you're using, and car radios tend to be more sensitive and selective).

You'll get more range on AM, but the sound quality will suffer.  Still, depending on your application and what you're playing, it may be the best choice.  Inexpensive AM transmitters such as the Talking House mentioned earlier in this thread will give you range in the hundreds of feet and they're easy to install.  There are much more expensive transmitters available that will give you better sound and much more range (if you install them correctly, which can be difficult - AM transmitters require a good ground system to get the 1-2 miles range mentioned).  Again, it all depends on your application, and how comfortable you are with the technical issues surrounding RF grounding.

Just make sure that you listen in on the frequency you intend to transmit on (and to either side of that frequency as well).  If they're clear, you should be good to go.  If you're located in a large metropolitan area, you might not have any choice but to go AM due to the lack of clear frequencies.  Listen during the daytime - at night, skip causes distant stations to come rolling in on virtually every frequency on the AM dial, and you'll really have no control over that (plus it doesn't count for an empty frequency - the FCC doesn't protect those signals as it does your local ones).

Thank you!

So if I understand correctly, as long as I am broadcasting in only about 200' in. each direction I should be okay?

Should I still get licensed through BMI for the months I broadcast? Because while I am really running a light show, I would like to have 24/7 Christmas music playing for me, and my neighbors like it too.

I just purchased an EDM Transmitter, however, now I am not sure if it is Part 15 compliant. I don't want to have the FCC knocking at my door over this.

Thanks again

-Nick

Nick,

The EDM should be OK as long as you limit its range.  It is sometimes confusing about "compliant" vs. "certified".  Compliant generally means the unit meets the FCC technical specifications of 15.239 as claimed by the manufacturer or seller, where certified means it has been tested to do so by a FCC acceptable laboratory.  Neither is a guarantee that the operation will be legal.  That being said, a certified transmitter used with the supplied antenna should be, but may not be, in terms of field strength.

If you use the EDM and adjust either the power or antenna to get about 200 feet of range you most likely will be OK.

Re the BMI license, I have no experience with this and trust that someone who does will comment.

Neil

I only know about Canada since I don't live in the USA but in Canada no music fees are needed for an over-the -air station not requiring a license.

I know this as I contacted all the music licensing organizations here.

Easy enough to find out. Contact by email as you can keep the response you get in writing and signed by a representative of the company. They may not even know what a part 15 station is.

It's pretty tough to get the EDM transmitter to be FCC Part 15 compliant (I've owned one).  You have to turn all power adjustments to their lowest levels, and even then that might not be enough - you would probably have to make the antenna shorter.

Also, that 200 feet is just an estimate.  Range is highly dependent on the sensitivity of the receiver, and if you use a deaf one (i.e., very poor sensitivity), you could still be well over the legal limit with a 200 foot range.  Similarly, using a car radio (which tend to be very sensitive and selective as a class), you could be under the legal limits with a 200 foot range.

The best way to avoid trouble with the FCC is to use a Part 15 CERTIFIED transmitter, preferably on AM (such as the Talking House).

As for music licensing, BMI is the only body in the U.S. that requires a Part 15 broadcaster to get a license.  Check out their website for details.  If you don't play BMI music (i.e., only use ASCAP or SESAC) you don't need anything.

Allow me to toss out my usual  random thoughts.

FM. It's the answer. I don't know about you, but get 200 feet or so from my house and you can't see my front yard anyway.  People watching your display will likely easily be within range. And you're broadcasting to cars, which generally have much better radios than any portable or home radio anyone is likely to have. Listening to a Part 15 FM is best done in a car anyway. Since this is a night light display, you'll discover noise and skip comes rolling in on the AM band once the sun goes down, and you'll wind up fighting it.  An EDM tweaked for proper power is a good choice.  I have an extensive review of the EDM posted at:

http://www.ironrangecountry.com/edmreview.pdf

Now, about that music license. You're doing part 15 broadcasting. ASCAP and SESAC do  not require a license for Part 15, BMI does. However, in a forum dedicated to Christmas light show people, it's been indicated that BMI has been contacted and they were told they consider displays such as this to be "private use" and no license is necessary. Again, just like the FCC, what the real deal is, is up to interpretation by whomever you talk to. Personally, I wouldn't sweat it.

However, if you were paranoid about it, i addition to sticking to only ASCAP and SESAC mucis, it's pretty easy to use all Public Domain Christmas music, as a lot of it was certainly written before 1922, and is free to use. BMI/SESAC/ASCAP only pay  songwriters. Artists only get paid through SoundExchange, which you only pay if you're streaming. So by using public domain music you would not be liable for any licensing fees no matter what. You'd be free to use any artist you choose, as long as the songs were PD.  Of course, this rules out using any popular or contemporary "hit" Christmas songs, but you'd be surprised how much is PD. This is one way to get around it if you're paranoid about it. Personally, I wouldn't sweat it. I know a lot of the big time light display guys use music from Trans-Siberian Orchestra for their displays and a lot of their stuff is traditional old school PD music (which also means they didn't have to pay any licensing to put out those songs on their CD's, which usually requires mechanical reproduction rights, and at their level of success that's a lot of dough).

OK, off to work 🙂

TIB

Nobody is Wrong

All the opinions given so far on this subject are true and correct.

I happen to own an EDM transmitter based on Tim's excellent review, and have set it for internal control room monitoring of my streams and AM signals, using a Decade GPL-32 Antenna which is wall mountable. (I hope I got the model number right).

Using a highly sensitive TECSUN PL-310 portable, which has a field strength display, I determined the field strength at which an FM signal drops into the noise, and I set the transmitter/antenna so that at 100' from my building the signal disappears. In my application I don't need that extra 100' (for a total of 200'), and there's nothing in that space but streets and yards.

A lightning burst at close range blew-out the final RF stage of my EDM, but I will have it repaired AND order another one because I like it so much.

I don't like Christmas, so I won't be doing any of that.

Thanks again everyone for all the advice.

This is a great forum to be apart of. You guys know a lot more about this than I do.

-Nick

Advice for Carl, If you fix or get another EDM remember to install a 2.2UH inductor across the antenna to ground. This is transient voltage protection and will save the output from static etc. on the antenna.