- April 28, 2019 at 1:54 pm #111004
Total posts : 609
I’ve finished all the testing I intend to do on this unit, as was discussed in the Rolls HR70 thread. Seemed to me that this should really have it’s own thread here in the forum as it really doesn’t fit the heading about the Rolls unit. The test, such as it is, is published at:
- April 28, 2019 at 3:16 pm #111005
Total posts : 468
Thanks for doing the test for us. Like I posted you confirmed that with a digital tuner it would be off and not received right and would need a analog radio to get it properly like the Sony ICF 801 or a radio with the TV audio bands. Even with audio cables it wouldn’t get you close to the 1 to 2 miles that thelegacy was excited about. Not as good as BETS-1 in Canada either.
- April 28, 2019 at 3:22 pm #111007
Total posts : 223
Thanks, Tim, for posting the link to your test results. Well done and informative and should be useful to those considering this device.
- April 29, 2019 at 11:11 am #111008
Total posts : 496
As Tim states in his test report, this device is certified under Part 74 of the FCC rules, not 15.236. Part 74 requires licensing, or at the very least eligibility for licensing and short term use, and is not applicable for continuous broadcasting.
One of the requirements of 15.236 is the ability to continuously check the Whitespace Database for other users of the frequency you are on (such as Part 74 licensed users, as well as other 15.236 licensed and unlicensed users).
Tim states specifically that he does not consider the legal ramifications of using the device. I don’t think that it would be acceptable for unlicensed broadcasting.
Other, similar but more expensive devices such as the Comtek BST-25 are also certified for Part 74 use. It makes me wonder if there are indeed any devices that are certified for 15.236 use.
- April 29, 2019 at 3:34 pm #111009
Total posts : 468
There’s a few posts about this on the Facebook forum and it has been said, by a few posters that until July 2020 these Part 74 wireless mics are also accepted as certified for part 236. Seems they got this info. from the FCC.
- April 29, 2019 at 6:00 pm #111011
Total posts : 253
Yes so you could use the BST-25 if it indeed is certified.
The poor performance of the ONN is a gig dissident but I’ll keep looking for a 50mW certified device.
Thanks Tim for your good work.
- April 30, 2019 at 3:47 am #111012
Total posts : 609
Again, I personally don’t want to get into the legalities of using these type of units. But apparently there have been a lot of changes to Part 15 in respect to the use of TV band whitespace. Info at:
Once you get there be sure to read the link for FCC 10-99 under the “Unlicensed Wireless Microphones” heading. This link downloads a pdf to your computer from the FCC with a lot of changes about part 15 and wireless microphones.
I have no intention of ever trying to use FM. My AM Procaster keeps plugging along and all is well for me.
I realize the intense desire for some to get their stations on useable FM. Sort of like the quest to use AM stereo. But the way I see it is, Part 15 already has limited range which limits potential audience. Why try to hard to use frequencies and technical formats that by themselves also greatly limit potential audience? I own probably 250-300 radios. From the 1920’s to brand new. Except for a couple vintage oddballs that tune TV audio frequencies on a slide rule dial from the 70’s, and a couple special interest radios of recent manufacture, nothing I have tunes these FM whitespace frequencies. The odds the general public will seek them out, and buy them to listen to a Part 15 station can’t be high. Not to mention no digitally tuned radio can land on the frequency, and no car radio that I know of can tune it either. Even old car radios from before digital tuning days won’t tune down that far. Unless listeners want to seek out a 1960’s Toyota radio with slide rule tuning. Further, none of these radios are stereo. And after my recent test and some poking around I can’t imagine anyone will find a wireless mic that will transmit in stereo. Consider how people listen to the radio. In the car. On a clock radio. On a stereo system or “boom box”. None of which will tune these whitespace frequencies. Growing like crazy is listening on a web stream, and now in hugely growing numbers via smart speakers, e.g. Google, Alexa, Apple speakers, etc.
There are literally millions of different wireless microphone and headphone transmitters out there made over the last 40 years. All the major makers of microphones have offered them. Not to mention the mountains of wireless guitar transmitters made over the past few decades. All of which I’m sure operate on the same groups of frequencies as the microphones.
It may turn out to be more trouble than it’s worth.
I mean, think about it. Lets say your Part 15 station has a total population of 250 people who can potentially receive it, they are in your coverage area. Now, subtract those who just can’t get good reception, maybe they only have crappy radios, or they live in a building where the signal can’t get through, or they live near something causing interference. Then subtract those who aren’t interested in your format. You could have the best rock, jazz or classical station to ever go on the air, but that’s not going to convince someone who wants to listen to country or rap to change their taste. If you want to attract the largest audience, based on current numbers you’d be a news/talk station. That’s number one broadcast format as of last year. At number two you’d be “adult contemporary”, next down the list you’d go for a Country format. Then “Pop/Contemporary Hit Radio”. So, if you’re not one of these formats most people aren’t interested in listening to you. And the whole point of Part 15 is to offer something “different” right? This limits your audience. Then by using a whitespace frequency below the FM band you’ve eliminated people who won’t seek out an oddball radio to even tune in your station. Same deal if you go C-Quam. Most people won’t bother trying to find a radio that will tune it in stereo. So you’ve taken your initial 250 people and it’s now whittled down to 25 who are capable of hearing your station and show an interest in your format. Then you limit that number further by making them buy a special radio. I just don’t see it myself.
As one who reads the radio trades every morning, in reality, if you want your programming actually heard you should be streaming or producing a podcast. Podcast ad revenue will surpass 500 million dollars in 2019. Most major broadcast groups now have podcast departments and producers. Current numbers show 1 in 5 Americans listen to a podcast each week. Sure, that’s only 20% but how many Americans listen to a Part 15 station every week? All this web based listening is generating tons of listeners and tons of revenue.
If you’re doing it because it’s a fun hobby that’s fantastic. If you can generate a few loyal listeners that’s great too. But if you really want the potential of a “lot” of listeners, or a chance to generate real revenue, Part 15 isn’t it. I generate a pretty good revenue but I’m not in a typical situation. I’m good at selling a lot of real cheap commercials, cover my tiny town with my signal, and have the audio streaming over a large cable TV service. People in a larger city simply can’t do this. You’re limited by the noise floor on AM and building penetration on FM. And a big city cable company won’t even consider putting your little station on their system.
Even if every adult in my town listened to my station that would be maybe 300 people. Streaming the potential would be unlimited. Yes, there are probably more than a million podcasts and streams out there, many with few if any listeners. But the good ones have listeners. And the very specialized ones have listeners. And even if you only had 32 podcast listeners, I’ll bet that’s more than the number of listeners a typical part 15 station has, and certainly more than a Part 15 that requires their listeners to find and purchase a special receiver to listen!
Ahh, just rambling on.
Overall it’s hard to say.
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