NPR requests FCC recall FM modulators

Hmmm... I guess there really are no standards to the testing that both labs used. If one says 76 percent, and the other says 40 percent, which one is right?

The link given would not open for me so I can only speculate that perhaps they used different make/model samples for the two reports.

As I understand this, it is not legal to market any factory assembled intentional radiator without FCC type acceptance or certification. So I ask how did these "illegal" devices get to market past the scrutiny of the FCC? For those of you who own one of these is it labelled according to the FCC requirements?

Neil

Despite the hoopla from NPR and NAB I can't find one documented complaint about interference from such modulators. I think it is largely a created complaint. Perhaps it's supposed to take attention away from the gross interference from HD radio broadcasting. That is documented and has caused the loss of reception of many stations to many people. Isn't it interesting that there are so many rules and regulations regarding interference with licensed stations, yet technology being embraced by broadcasters does exactly that. I know I have mentioned this many times before, but NPR and the NAB and many broadcasting corporations can't seem to figure out that their declining listenership is due to lack of localism. So many stations simply want a cheap satellite delivered program service and there is simply nothing unique about the programming. On another forum I visit one of the members said that he dropped his resume by a new station (new ownership) and found that they had no studio. There was equipment for emergency alerts, etc. But the station did none of their production on site and were not set up to broadcast live other than a microphone cut-in for emergency use. If all I'm getting is canned music and some commercials, why not skip the middle man and simply tune into satellite radio and hear the tunes commercial-free?

On another forum I visit one of the members said that he dropped his resume by a new station (new ownership) and found that they had no studio. There was equipment for emergency alerts, etc. But the station did none of their production on site and were not set up to broadcast live other than a microphone cut-in for emergency use. If all I'm getting is canned music and some commercials, why not skip the middle man and simply tune into satellite radio and hear the tunes commercial-free?

What kind of station was this? They are still required to have a certain amount of local programming, which I think includes having live staff. If that were not the case, my local Cheap Channels would have packed up long ago and run everything from headquarters in Texas. I know that LPFM distinctly requires a certain number of local hours (suggesting live people), and I'm pretty sure the same applies to the full power stations.

I still think the idea of an independant test of these part15 devices is in need, but the broadcasters and the FCC will not listen to us little guys, even if we have the most expensive (and brand new) equipment to perform the testing. All the "firms" that have been hired to test this stuff, have been hired to make sure they find a problem, and then report it.

Maybe when the weather gets nicer I'll have to fire up my FM25 on a local channel and see how far I get before the full power station takes over. If I had an HD radio I would try the same on the digital half too (or is that digital two thirds?).

Live, local content has been argued about for the last couple of decades or more, ever since the change in the ownership rules occurred. The fact is, the FCC got bit big time when a local emergency occurred in the Upper Midwest a year or so ago and the local emergency manager couldn't get a hold of the Clear Channel radio station in the town to get the word out for local residents to evacuate. The station was being run in "unattended" mode. It wasn't against the rules at that time to operate in such a mode. However, just recently, the FCC has reevaluated "unattended" operation and has deemed it necessary to have someone who could be contacted if an emergency occurred.

That issue is different from the issue already on this thread. Stations CAN operate without a local "sound" studio, but must have a way of communicating to their local communities in the event of an emergency. A microphone, a small mixer hooked to the audio chain is all that is required by the rules. Local issues and local programming can be programmed from anywhere on the planet, according to the current rules. The "public file" with a list of the local issues and the stations activity in addressing those issues is still required in the city of license. A new proposal even moves the control studio for a licensed station to 50 miles away from the city of license. The local service rules aren't tightening, they are, in fact, loosening up.

Maybe you get the idea that localism is dead. And in this age of technolgy based broadcasting, being local just isn't economical or necessary anymore. Well, I don't believe that for a minute. And you're correct when you say you can get the same thing only better from XM and Sirius. Enters the local Part 15 radio enthusiast who can cover all the sins of the licensed broadcaster. Bingo. That is the story we need to tell local leaders over and over again. Then have them tell the FCC, the little guys better serve their purposes.

And by the way, the experimentation with radio gear has been relegated to the amateur bands for years. I think it needs to stay there. Part 15 should allow people who want to take what they have learned elsewhere and put it into practice. But, unless you experiment in a closed, controlled environment, someone will eventually interfere with a licensed service. And the arguement you shouldn't need to acquire a license just to play around with the public airwaves is faulty even in it's basic logic. The case to be examined carefully is the sensitivity public licensed broadcasters have to interference from FM "mods". Like it or not, a Part 15 broadcast transmitter is the SAME as an FM "mod" to the FCC and the NPR folks. So, the certififcation and testing of transmitters is no assurance the device will be installed or operated legally. In short, the responsibility still remains with the guy who flips the "on/off" switch.

Marshall Johnson, Sr.
Senior Pastor, President
Rhema Christian Fellowship, Inc.

Rhema Radio - The Word In Worship
AM 1660 - FM 93.5
http://www.rhemaradio.org

And the arguement you shouldn't need to acquire a license just to play around with the public airwaves is faulty even in it's basic logic.

Sorry, but your belief about this is just plain ludicrous.

Do you really think that your wish to "play around" with the public airwaves supersedes the needs of the public as defined by the Communications Act of 1934? And what if your operations, and/or those of your followers interfered with police, 911, fire and/or other emergency communications services?

Even licensed AM/FM/TV broadcast stations deserve the interference protection ratios determined by the FCC Rules governing them. You are not entitled to re-define them for your purposes, without due process.

If you believe that what you have posted is valid, then you are free to act on those beliefs by introducing legislation to change those Rules.

Unless and until your desired changes become codified by the FCC, I suggest that you refrain from posting your personal opinions on the same which are contrary to existing law.

//

Interesting comments but it seems that threads regarding a technical question, namely "are these devices part 15 compliant or not?", tend to drift to programming issues regarding licensed broadcasting.

There is room for these discussions but I would get back to my question stated earlier in which I asked how these devices which apparently violate part 15 rules appear on the US market.

I don't know the answer, but it seems that either the rules are not adequate to prevent the alleged interference or that many of these devices are slipping through the regulation net. If the devices cited in the NAB and NPR studies exceed the FCC radiation limits and are being sold in the US doesn't this point to a problem with FCC oversight rather than the actions of the mostly unknowledgeable users of these devices who just push the "ON" button so they can hear their programs?

Perhaps a study of selected "non-compliant" devices according to the NPR and NAB reports done by a FCC lab could remove any real or perceived bias. In science, replication is critical in pursuing the truth.

Neil

Perhaps a study of selected "non-compliant" devices according to the NPR and NAB reports done by a FCC lab could remove any real or perceived bias. In science, replication is critical in pursuing the truth.

Neil

In a previous thread ( http://www.part15.us/node/1036 ) it was raised that we should get together and either prove or disprove these findings. The problem that I see with this is who are we to argue against a so called knowledgeable engineering firm that found these devices to be out of spec. After all, they must know more than we do, they run a company based on that knowledge....

Challenging those tests is still a good idea, but it would require a "reputable" firm to do the testing. Or it will require the FCC to do the testing under their official rules.

I just read the report, and there are some holes. If two vehicles happen to be in the detection zone at the same time, and transmitting on the same channel, then isn't the field strength going to be much higher? Also using a average distance between the lanes of traffic is really very flawed. If a part 15 FM has a range of about 200 feet, then the signal strength over a distance of twenty or forty feet is going to be an large variance (difference between the closest and farthest lanes). Two lane roads are approximately 20 feet wide or more, 4 lanes roads are going to be more like 40. I'll give them something for the effort, but unless you can sample a single lane then things are not going to be accurate enough. They would be better off trying this in a tunnel where you can put the antenna in the average width of the road. Maybe on a bridge would work too. The only other way to do this is to move the receiving antenna far enough away from the traffic that the distance between the cars is very small compared to the distance between the cars and the antenna.

Footnote, normal highway lane widths are slightly more than 12 feet wide between the painted lines, plus the shoulder area. Vehicles can not be more than 12 feet wide without a special permit. If my memory is correct, more than 10 feet wide requires a "wide load" sign, but I could be wrong.

Greg,

I believe you and I agree on this. If I were, and I am not, an FCC official I would encourage a FCC lab study to confirm or refute the technical results of both of these studies. But then I have to ask myself "why?". What will be done with the data?

The topic of whether these devices are a real interference problem is another issue. When I lived in Cincinnati, there was a TV commentator named Sam Johnson (who if anyone here is old enough to remember could have been Pat Paulson's twin brother) who said "It depends on whose personal ox is being gored."

Some licensed broadcasters seem to be concerned about their ox relative to Podcasting and some part15 operators posting certainly are worried about their oxen, and I am coming to believe that both parties should just be quiet and not stir the pot and accept things as they are. The problem here, for us, is that the licensed broadcasters do not have to be quiet.

I challenge anyone to convince me that part 15 rules were ever intended to facilitate community broadcasting. When we stretch the rules and technology beyond the intended purpose we expose ourselves to review and rewrite of the regulations. My advice is don't pull the tail of the bull.

The fact is that by law the licensed broadcasters have privileges which supersede those of part 15 operators. I am a licensed amateur radio operator and I enjoy legal protection for my operation on the assigned bands with the expectation that I can operate without interference and I am willing to grant the same respect to licensees on the other bands.

Those who want to pursue community low power broadcasting should do so, but in my opinion it will have to be done outside the current part 15 regulations.

Neil

If only there were more channels, even if those channels were only up to 10 watts (effective). With the location I have at school, I could cover most of our desired area with about 1 watt and a good antenna. We are a community college, so all but about 400-500 students commute everyday (we added some dorms this fall) which is about 8000 total students this semester. It would be really nice if we could reach our students with things like class cancelations, morning traffic, parking issues, etc., and reach them before they arrived. But there are NO FM channels in our area, and there is no LPAM class yet, so this leaves part 15 and the internet. The problem with the internet is that it is difficult to get in your car. The infrastructure just isn't there yet (in our market).

So when the big broadcasters start yelling about things that don't really effect their protected curves (while they get their 3 for the price of one with digital), I get a little irritated. Now if those devices really do have too much signal strength, then the manufacturers should be made to correct the problem. If they don't really have too much power, all the big broacast funded organizations should leave well enough alone. The end all be all judge of this has to be the ruling body (the FCC). And making a summary ruling about unknown devices should not be allowed, what if the end user illegally modified that transmitter. No one knows if the transmitters in those cars had been modified, and they don't even know if more than one car on the same channel went by. At least the NAB sponsored test had a clear cut methodology with know tranmitters. I would have been a little more happy with the NAB report if they had used an antenna that was meant to be used with their spectrum analyzer. This NPR report should be completely discounted for it's lack of error correction and unknown variables.

First of all to Neil: I do have a part 15 modulator for a CD player. It is labeled as such. As far as others getting to market there is no problem with that anymore. The FCC can't keep track of everything. Without mentioning names I'm sure a major retailer would have no problem moving a bunch of modulators sold with audio devices regardless of any labeling. Most people don't know about the regulations and others just don't care. You are right that most people just push a button without any idea of how the device works or if it is in compliance with any rules. For that matter you can buy a full power transmitter without question from many sources, even without license documentation. It's not even illegal for me to own a full power transmitter. However if I put it on the air that would change. I disagree about part 15 experimenting. True, the purpose of the original part 15 rules was not community broadcasting...there were locally owned and programmed stations at the time. Neither was it the intent of the FM translator service to be the backbone of satellite delivered religious networks. I find experimentation to be one of the fun parts of part 15 broadcasting. As long as I am in compliance with part 15 regulations it shouldn't matter. We are so comfortable with our compliance that we even use local newspaper advertising and helped sponsor a local theatrical production.

To Rich: I think you are disagreeing with someone in your post that shared your opinion. I disagree with you about posting opinions. Unless I am mistaken, that is the purpose of thie forum to share information and opinions. Your belief that any experimentation is automatically illegal is faulty. Some of the worst engineering I have seen has been at licensed broadcast stations. If laws are to be changed, discussion is necessary. So far the most serious intereference to public service communicatiosn has been from licensed commercial broadcasters. Let's not forget that many FM stations used to leave their exciters on all night after shutdown of their main transmitter resulting in a few watts of signal without content or ID. (Interference) The NAB study certainly doesn't use sound (pardon the pun) practices or techniques to draw their conclusions. A lot of it is legal heresay and much of the rest deliberately set up to reinforce their agenda. The NAB also fought to prevent any FM translator station from having local origination of any type. Exactly how does that serve the public?

And to Greg- The easiest way to get more stations would be to require Class C FM stations to reduce power. That's one of the subjects our radio group is researching. We're taking surveys to determine listenership distances for FM stations. The spacing requirements for higher powered FM stations are so great that a few stations can wipe out what could be available frequencies for a huge distance.

I know I've wandered way off the original topic, sorry. Even if the FCC asked people to return their modulators how could it possibly be enforced? Most people just wouldn't want the hassle of taking it back to where they bought it, especially if it serves their needs. Most sales would lack any customer information so letters would be pointless. Perhaps my age is showing but the worst intereference to my radio listening in a car is someone in another car with their radio turned up too loud.

Techpuppy,

Thanks for your comments, especially as they pertain to the proliferation of "mods".

Without going into great detail I recall the CB situation before and after the 1970's. The formerly licensed service evolved into what it is due to the unmanageable number of people who went on the air without licenses. So, the FCC ceased regulation of operations by dropping licensing but it clamped down firmly on equipment specifications including a prohibition of an external amplifier which could operate legitimately on the 10 meter amateur band.

I would regret such a regulatory response which would have a similar effect on part 15 AM and FM as we now know it. All equipment except factory built and FCC certified transmitter/antenna combinations, and even these, could be banned which would certainly end the experimentation.

Neil

What will and probably has happened is the FCC Laboratory in Columbia, MD has requested samples from the manufactuers.

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John
Owner-Operator-Chief Engineer-Program Manager