- April 17, 2019 at 1:34 pm #110907
I already posted this string of random comments in the FB Part 15 group, but for others:
Well, there are several comments I have here. First of all which name/model headphones? There are many “ONN Wireless Headphones”. Second of all, what did he have to green light? Thousands and thousands of people have purchased these and used them to transmit music from their audio systems and computers to their headphones. How is that any different than running your station into them? I know an awful lot of radio pros working in studios using wireless headphones in the studio while on the air, which means they are “broadcasting” their radio station on 84.922 as well as whatever their commercial broadcast frequency might be. How do these avoid interference if, say, your neighbor or guy down the block decides to use wireless headphones? It’s not an official “Hobby Broadcast” frequency. It’s just broadcasting your hobby station on an already available frequency already being used for transmitting music. Now, I own probably 200 FM radios, from portables to receivers, newer and vintage. I don’t believe I own ONE that has a way to simply “throw it into Japan mode”. And neither will the typical man on the street. I do own one Sony, from Japan, which has the expanded FM band, slide rule tuning, and even though it’s a smaller mono radio I think it has stereo headphone output. Can people get it on their clock radios? In their cars? I see some limited use here. All that being said, I’d love to do some range and field strength tests once I know what the exact model is. It appears several brands of wireless headphones use this frequency. I do see one potential good use not mentioned — as a studio/transmitter link for AM. I also like the suggestion of using old radios with TV Band audio reception. I own several of these. All are mono, but always had good sound. But they had analog slide rule tuning and would have no trouble tuning in the somewhat odd frequency. Experimentation to begin. The Sony radio I have with the expanded band is a Sony “2Band Radio” ICF-801. It has the expanded Japanese Fm band, slide rule tuning, runs on batteries or A/C power with a power cord, NOT a wall wart power supply! The sound is excellent. They seem to have gotten rather expensive however. But great little radio with great speaker sound.April 17, 2019 at 2:36 pm #110909
ONN FM Wireless Headphones ONA14AA011
FCC ID 2ABV4-ONA14AA011
Tim I’d love you to do some tests with these. The agent did tell me down on part 15:236 its Power so you don’t have to worry about the field strength. In the agents tests it actually put 50 mW and as he told me the Range will be funny but if I could get my transmitter high and near water it may go further. It was why the gentleman who posted about his experience and going all the way out on a lake with his boat and still hearing the Headphone transmitter loud and clear.
Most Wireless headphones I came across were on 900 Mhz but what I like is these do transmit down on the Japanese FM and TV sound bands where people may be able to get a good TV sound Radio next to nothing or pay a bit for a highly sensitive Radio. Some did have good Mono sound and I think some Album Rockers would listen. I’ve heard Mono on some good Sony Radios and I didn’t mind that too much. To me it still sounded way better than mono AM.
I want to give my listeners a choice between C-Quam AM Stereo and this way to listen and since the headphone transmitter transmits Stereo an analog Stereo tuner would get it. Maybe a Stereo Radio with TV Sound could be modified to receive FM Stereo in the TV sound band on VHF Low. I’m excited to find out.April 17, 2019 at 3:27 pm #110911MarkModerator
Total posts : 598
Yes that Sony ICF-801 is still available on Ebay new but used to be under $100 + shipping but now for some reason the price is around $250-$300. Amazon has none. Whole page of them on Ebay.
But can you convince potential listeners to get one of these?April 17, 2019 at 4:02 pm #110915
Well, that’s just one of many radio options. I bought mine a couple years ago and they were less expensive.
But as was mentioned, there are thousands of radios with TV audio band in them that would work quite well. I have several multi band portable radios from the 70’s and 80’s with great sound that would work.
Still easier to find a suitable receiving radio than trying to come up with a readily available C-Quam AM receiver I’d say.
I must say, I still vote “skeptical” on this transmitter idea, but time and some experimenting will tell more.
I did just read the complete certification report at the FCC site, and as was mentioned, for this frequency the limitation is power output, not field strength. The limit is 50 mW, however the test report and the FCC specifications clearly show the output of this transmitter to be 5.50 mW. That’s 5 point five, or just above 1/10 of the limit.
I have ordered one to play around with. They’re practically free.
TIBApril 17, 2019 at 8:03 pm #110917
Let us know which TV receiver or radio that receives this frequency has the best sensitivity. I think that’s going to be the key.
I saw the test report too and I thought it said five milliwatts but the agent was saying Tumi 50 microvolts. He did say there are other models that will go down there too that transmit audio. So if this one doesn’t do it we should look for the one that gives you the full 50 mW and has the certification on it.
I saw one similar model where the transmitter only would run on batteries and I saw a different one where it will do electric or battery. If it’s the case maybe what’s happening is the one that runs on electric is using that ground wire as an antenna which means plug it in and it’s acting sort of like neutral injection carrier current. And since there’s no field strength rule as long as you don’t modify that unit and you’re running it as instructed it’s making you get out further than the batteries will. That could be where the 1-mile reception happened from the person that was on a boat.
We definitely have a play toy.April 17, 2019 at 8:25 pm #110919MarkModerator
Total posts : 598
Looked up the certification and saw this complies with Part74 and states this item is for NON- BROADCASTING. Also saw the word licensed with part 74.
Just going by the non- broadcasting it means the intent can’t be getting out to the general public. This is similar to the Canadian definition of broadcasting and non-broadcasting. It was certified to get to you as the user with headphones, not to broadcast to a radio for the general public.
This certification that Tim posted is definitely not in accordance with part 15-239, which, is the section in question when this subject started.
Not trying to sound like Rich but this may not be the big loophole to get lots of power on FM that it seems. I still am skeptical till I see how thelegacy does with it and I think thelegacy should check again with his agents and show them this certification. And if the agents say it’s OK, get it in writing.
Canada has a section in RSS-210 on wireless mics also and it also says max 50mW on the VHF frequencies below the FM band but like I said, until I see different I don’t think it is a way to get a license free broadcast station on FM with a lot more power.April 17, 2019 at 11:34 pm #110922
When a complaint is sent to the Enforcement bureau David Dombrowski is the one who sends this agent to shut down those who violated the rules. David and I too have spoke on the phone a few times when I called to talk to the agent that visited me and he is aware of my correspondence. Technically part 15 section 236 was Not meant for broadcasting but as the agent said no NOUO will be issued to me so long as I use a certified non modified headphone or Wireless Audio sender I asked about posting 84.922 Mhz doing my Album Rock show promote where to buy the special Radios (That is the loopwhole) to receive my Hobby Broadcast.
Knowing how the FCC listens to my station on the net (They told me they do) they are Well Aware I was gonna post it. Timinbovey ordered his for testing so we will see.
The agent laughed at my idea in a good way and he knows if people want to listen bad enough they will buy the Radios. It’s the best its gonna for a close replica to New Zealand. I’m sure agents are laughing at how I figured this out. I’m a real Radio geek having fun.April 18, 2019 at 1:22 pm #110926
If you read the full report you will see it is ALSO compliant for 15.236 and in fact has a FCC ID issued for part 15 certification.
I was a bit concerned about a couple other details — the rule states:
“(b)Operation under this section is limited to wireless microphones as defined in this section.”
And the definition in this section states:
“(1)Wireless Microphone. An intentional radiator that converts sound into electrical audio signals that are transmitted using radio signals to a receiver which converts the radio signals back into audio signals that are sent through a sound recording or amplifying system. Wireless microphones may be used for cue and control communications and synchronization of TV camera signals as defined in § 74.801 of this chapter. Wireless microphones do not include auditory assistance devices as defined in § 15.3(a) of this part.”
Which doesn’t include broadcasting.
But on the other hand, there are an awful lot of wireless headphones offered on this frequency, and everyone using them would in effect be ‘broadcasting”.
TIBApril 18, 2019 at 6:12 pm #110928
I don’t know why Michelle Bradley could not find the report for 15:236 on this device? So is there another similar one with 15:236 certification just in case there is an issue so I don’t get busted? (I doubt it) but lets cover our bases.April 18, 2019 at 6:30 pm #110931ArtisanRadioParticipant
Total posts : 526
Whitespace devices have been around a while, and the issue has always been whether broadcasting was an acceptable use. It appears, at least from this one agent’s comment, that it would be OK, as long as all the other provisions of the Whitespace rules are followed.
In my opinion, broadcasting is problematic in any event as the onus is up to the unlicensed user of these devices to continuously check the Whitespace Database to ensure that they will not be causing interference to those that have registered. Presumably on a daily basis, if not more frequently.
The other issue is, of course, the radio one. You need a radio that will receive Whitespace frequencies to receive a broadcast on those frequencies. You’re going to need really loyal listeners for that.
On a side note, Mister Wonderful (the Webmaster at another website) is at it again. A day or so ago I saw some disparaging comments about ‘pirates’ posting on other (maybe this one) sites about operating on the Whitespace frequencies, including 87.9. He talks about how this frequency is off limits for Part 15 (presumably 15.239) broadcasters. Of course he’s right, but then, these whitespace devices are NOT operating under Part 15.239. As long as they are certified under the correct Part 15 rules for their frequencies, then the only real issue is whether the FCC would consider broadcasting acceptable use.
I don’t see why not, but then, I’m not an FCC agent.
I know in Canada, the Whitespace frequencies are governed under RSS210, which does not allow broadcasting to the general public. However, broadcasting within a confined area is not considered broadcasting (RSS123 is a licensed version of this) so you COULD, theoretically, broadcast wihin a mall, or arena or similar area using a certified wireless microphone.April 19, 2019 at 11:49 am #110862John SeesParticipant
Total posts : 41
Perhaps you could use it under 15.236 as a wirelesss microphone on 87.9? It looks like it tunes down that far and the 40 milliwatts output is under the 50 allowed for wireless mics. The 15.236 definition of wireless mics is pretty loose and I don’t see any restrictions as to uesage, transmitted content nor intended audience…
W9LWAApril 19, 2019 at 3:06 pm #110943
I believe “Mr. Wonderful” is right that these are not applicable for 15.239 use. However, they ARE available for use under 15.236. This is clearly spelled out in the FCC’s “Wireless Microphones Rules Update” of 11/1/2017.
It states 76 – 88 mHz can operate under 15.236, unlicensed, with a maximum power of 50 mW EIRP. And also operate under Part 74 Subpart H, licensed, with the same maximum power of 50 mW EIRP.
Again, every bit of documentation I can find for test and certification results for the transmitter discussed here, the output is stated at 5.5 mW, far under the legal limit. And with the tiny antenna enclosed in the case (you can see this in their certification paperwork) I would not be surprised if range is similar to a legal Part 15 FM band transmitter.
I think when we come down to discussing if this can be used for “broadcasting” consider — likely tens of thousands of consumers purchased these to enjoy headphones connected to their stereo, computer, TV or whatever with the convenience of wireless connectivity. If they listed to their favorite radio station or TV station are they then not for all intents and purposes broadcasting? I mentioned before, I have known several radio announcers at commercial stations who use wireless headphones while doing their airshafts, so they may move about the studio, music library, etc without removing their headphones and dealing with the cord. Hence, their entire show is being “broadcast” on the frequency of their wireless headphones.
Certainly the use of these headphones is legal for their intended purpose of broadcasting sound to listen to wirelessly. They have all sorts of documented certification and lab tests, and are certified for use under two different classes. Whether you decide if they are legal for “broadcasting” I think, is a bit of a matter of interpretation.
Anyway, the one I ordered has been shipped. I’ll give it my usual FM Transmitter tests. RF output, field strength at 3 meters (just so we can compare it to a 15.239 unit), modulation capabilities, and some rather unscientific range testing.
Couple oddities. I note it also includes a built in FM radio. And It also states that if you are trying to listen to your audio being transmitted from it’s base and experience static or interference you need to press a button to “select a different frequency”. There’s more than one?
We’ll see once it arrives.
TIBApril 19, 2019 at 4:51 pm #110946ArtisanRadioParticipant
Total posts : 526
Mr. Wonderful was calling users of such devices pirates. At best he was being disingenuous, at worst deliberately misleading. It doesn’t appear that there’s anything wrong with using these Part 15(.236) certified devices, unlicensed, on the frequencies between 76-88 Mhz, as long as you don’t cause interference with other licensed users, or unlicensed users that have registered in the Whitespace Database.April 19, 2019 at 7:00 pm #110952
There is a Zimtown Wireless headphone that transmits on 86 Mhz but I can’t find any FCC certificatation for it. A lot are on 85 Mhz. Station8 found this but its way too expensive @ 300 dollars but does have full 50 mW output but has a bandwidth for the FM modulation of 90 Khz for the deviation. I know standard FM is +- 75 Khz for deviation so that is not cool even if I could afford it. It transmits from 76-88 Mhz.
The Rolls transmitter may be usable but does it come with FCC certification? Does it come with an antenna? I gave away my ground plane to a Ham after I got visited because I didn’t know about this holy grail and after I mentioned that the agent told me He didn’t say I could never use FM just have to use certified equipment. But the Rolls (if certified) I’m sure may have issues with a ground plane. Telescopic antenna maybe. But the agent said down there its not a field strength issue its a Power issue. The ground plane I had was 3db gain.
I think having an FM antenna too close to my AM transmitter is not good either. If the rolls is certified I could use a telescopic antenna for it and call it a day.April 19, 2019 at 7:03 pm #110953
Oh there was a dude on Facebook that also called the FCC and told them what I was doing. The other agent also told him the same thing. I’m sure David Dombrowski is having a cow now that I discovered this but never got the call on the phone from the FCC telling me to cut it out and stop posting it.
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