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Synced Part-15s taking up the slack for daytimers?

I'm sure this has been asked or posed as an inquiry before, but I'll ask anyway: Does anyone know of an AM daytimer that utilized Part-15 broadcasts to take up its broadcast after the full power sign-off? This would seem to be a way to have fulltime broadcasts in lieu of an FM translator--for perhaps downtown residents in a small-town license.
 
Yes. Radio Omega, formerly of Lebanon, PA did something very similar to this. They actually brokered out time on AM 1600 in nearby Anneville and programmed the Part 15 AM signal over the licensed AM station! I seem to recall that it was only a daytimer and that the Part 15 AM signal carried on 24 hours a day.
 
The following paste from an earlier R-I thread may be of interest to those considering the use of several "synced," unlicensed, AM broadcast band transmitters expected to be permitted by Part 15.

The question was posed to, and answered by the FCC Office of Engineering and Technology (OET), and is pasted below verbatim, along with their unedited response.

Q: In http://fjallfoss.fcc.gov/oetcf/kdb/forms/FTSSearchResultPage.cfm?id=20973&switch=P, it states, "In paragraph 137, the Commission stated that it concurred with the comments that multiple devices should be permitted provided, the individual transmitters comply with the rules and any emission resulting from the simultaneous operation of the individual, non-coordinated transmitters complies with the rules."

Could the OET please define what is meant by "non-coordinated" transmitters in the above quotation? If two or more Part 15 AM intentional radiators are installed near each other, and all use the same, synchronous carrier frequency and modulation then their radiated fields would produce an extended coverage area compared to a single, compliant system.

Is such a multiple system considered to be compliant under Part 15?

A: The term non-coordinated in practice has been used to mean independent transmitters so that the transmitters do not employ some method to cooperate so that simultaneous transmissions result in being non-compliant or not within the scope of the Part 15 rules. The scope of part 15 is to permit a low power independent device to radiate with out a licensee in a localized area. The specifics will depend what rule parts are being used.

In your case the part 15.219 devices using multiple transmitters transmitting on the same frequency and carrier phased synchronized to effect larger coverage area with the same information considered coordinated and not permitted.

The effective air-signals would be equivalent to a signal transmitter exceeding a rule part in you refers to. Something similar to this may be applicable to a confined area under 15.221, but would require a detail review by the FCC before it could be certified.
//
 
the way you worded it fry would probably make the FCC thing you we're literally putting the transmitters right by each other. Most synced up Part 15 stations transmitters are spaced about a mile if not more.
If that was the case Fox Sports 1650 in Flagstaff would have been shut down years ago.
 
LibertyNT said:
the way you worded it fry would probably make the FCC thing you we're literally putting the transmitters right by each other. Most synced up Part 15 stations transmitters are spaced about a mile if not more. If that was the case Fox Sports 1650 in Flagstaff would have been shut down years ago.

Just to note that if multiple, intentional radiators on the same AM broadcast band frequency functionally meet Part 15.219, and they are located "about a mile if not more" from each other, then there is virtually zero need for them to be synchronized in r-f and/or audio (program) phase.* And the operators of such co-channel systems would save a fair amount of their hardware cost and setup aggravation.

This also corresponds with the statements in the OET answer posted earlier in this thread, "The scope of part 15 is to permit a low power independent device to radiate with out a licensee in a localized area. In your case the part 15.219 devices using multiple transmitters transmitting on the same frequency and carrier phased synchronized to effect larger coverage area with the same information considered coordinated and not permitted."

By definition, an "independent device" cannot depend on one or more external synchronizing or programming inputs if it is truly independent.

* see the green circle in the graphic at http://i62.photobucket.com/albums/h85/rfry-100/150_microvolt_per_meterRadius_Part_.gif

//
 
In your case the part 15.219 devices using multiple transmitters transmitting on the same frequency and carrier phased synchronized to effect larger coverage area with the same information considered coordinated and not permitted.

So I am guessing that if the transmitters were operating on different frequencies that would be legal in your opinion?
 
Transmitters operating on different frequencies are definitely not phase synchronized. Even transmitters at zero beat on the same frequency, but not locked in phase, are not synchronized. Synchronization is the same as having two or more transmitter output stages driven by the same oscillator. Synchronization is useful only if the coverage areas of the transmitters overlap. If the transmitters are far enough apart so that there is no overlap in coverage areas, synchronization serves no useful purpose.

Is "synchronized" the same as "coordinated?" Only the FCC knows for sure. I don't know of any enforcement actions in this area.
 
druidhillsradio,

Since you have are slightly bent sense of humor, I sometimes don't know if you are asking a serious question, or you are kidding. If you were kiddding, please pardon me for replying.
 
druidhillsradio has a kind of sense of humor more typical of Europeans than Americans. Rush Limbaugh's humor is like that, too. That is why a lot of his listeners who don't tune in regularly don't get his jokes.

Arnold Schwarzenegger had a little fun with somebody who asked the meaning of his last name. He said that it means, "black plowman." That's a possible translation, but not very likely. Some kidders say it means, "black negro." That's also impossible. In modern German, the word for "negro" is spelled with only one g. Even though German spelling has changed over the years, it is still not possible. Most likely, Schwarzenegger is somebody from a place called Schwarzenegg, which means, "black ridge." Arnold's ancestors must have been from some mountain area.
 
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