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Post by Variety 1560 AM on Mar 17, 2016 8:43:25 GMT -7
maybe we can sell at as not broadcasting "per se" but as a general low power experimentation band where people can try different modulation methods and antenna designs, etc.
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Post by davidchamberlain on Mar 17, 2016 9:03:37 GMT -7
IF we propose that LPAM commercial stations go in that band, then that's inviting the NAB back in.
I was thinking of a modified New Zealand approach - a couple of channels above the AM band, maybe even a couple below, dedicated to hobbyist broadcasting for experimentation & innovative programming. Small enough that the NAB won't want in (hobbyists won't get anything that has perceived value-it has to look as worthless as possible). And to make it simple, no restrictions, just a maximum ERP (it could be 100 milliwatts or even a bit more).
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neil
New Member
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Post by neil on Mar 17, 2016 9:09:45 GMT -7
Hi Folks,
New to the site but old to Part 15 activity. This is Neil aka radio8z.
Interesting read so far and nothing to add now except Hello.
Neil
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Post by Variety 1560 AM on Mar 17, 2016 9:38:18 GMT -7
i like that idea David. 2 up 2 down and 100mW erp, no antenna restrictions.
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Post by Variety 1560 AM on Mar 17, 2016 9:45:37 GMT -7
just enough to do something with while limiting potential interference between stations. and again like i suggested on long wave, practicality will be the limiting factor on antenna, not many people will have the ability or finances to put up a large 1/4 wave monopole over a full 120 radial 1/4 wave ground plane.
most will be able to do 30-50ft at most with a top hat and base loading, over a small maybe 20ft ground plane. 100mW ERP, would have to specify if that will be pep or rms.
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Post by davidchamberlain on Mar 17, 2016 10:57:01 GMT -7
I believe it's RMS now? I don't think we should touch the existing Part 15 rules - just add to them. I know that Canada for a while only allowed its BETS-1 field strength limits on a few channels at the top & bottom of the FM band to limit interference - hobbyists using the rest of the band had to use RSS-210 (i.e., Part 15) field strength limits. So there is sort-of precedent here from elsewhere in addition to New Zealand.
If Rich joins in, or even if he doesn't, it would be interesting, no matter what is eventually decided, to do some simulations using NEC on those frequencies to see the field strength contours (as well as potential adjacent channel interference) with that kind of power & ideal antennas (which would give you maximums).
As for shortwave, it's an open question in my mind if the ITU had to be involved with what would be a domestic shortwave service. I know that in the amateur radio world, a couple of watts with CW can get you great distances, but we're talking here about AM, SSB and potentially things like DSB. We could even eliminate digital modes from the equation. We're going to have to get someone in who has some experience in dealing with shortwave licensing.
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Post by Variety 1560 AM on Mar 17, 2016 11:55:17 GMT -7
so we are talking RMS ERP of 100mW (500mW pep), and center frequencies of 510,520,1710,1720 with band edges ranging from 505 to 525 and 1705 to 1725. we would need NEC simulations, maybe some temporary part 5 licenses on those frequencies under our proposed operating technical standards to study potential interference and potential sky wave issues, we would need to layout what the technical and operation rules would be, etc
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neil
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Post by neil on Mar 17, 2016 16:52:21 GMT -7
The idea of the two bands, above and below the AM band, is worth discussion but if we propose using an ERP specification then we are entering a situation where this could not be measured and it would depend on the antenna system characteristics. It seems the working approach would be to use the antenna system input power, tricky to measure, and calculations or tables to estimate the ERP. This would be difficult and tenuous.
I am pulled back to using something akin to the input power and antenna length limits similar to 15.219, but with different numbers, especially much longer antenna length limits which could drastically improve antenna system efficiency.
Neil
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Post by davidchamberlain on Mar 17, 2016 17:48:21 GMT -7
That's a good point, Neal. We could estimate what a reasonable input power would be, given some loosening of antenna & ground restrictions, to give us, say, 100mw ERP (and tweak it if need be once the contour calculations are done).
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Post by davidchamberlain on Mar 17, 2016 19:02:38 GMT -7
So, I've done some googling on Part 15 and LPAM petitions. There have been a lot of them. All of them focused on relatively low power in the existing band. I haven't found one, at least yet, that asks for extra channels for this service (that could be both good and bad).
Some other thoughts/comments. One suggestion was that the FCC liked to focus on measurable, economic arguments - I don't know the validity of that. But they certainly don't focus on arguments that have the hobbyist or low power operator front and center. There have been lots that have waved their arms and talked about the diversity of radio, bringing it back to the people (or community, or local ownership), etc. With no results.
The FCC does have a strategic plan (I found it and posted it over at The Initiative, where it was promptly ignored). They have to at least consider arguments that address specifics in that plan (even though it was fairly general, as most strategic plans are). There's no harm in quoting from that plan when compiling the petition.
I can post that plan here if people want, although it's fairly easy to find on the net.
I also found a petition (or suggestion, not sure if it ever went to a petition) that really reads like my amateur broadcast license suggestion on shortwave. And like amateur radio, you have would to demonstrate some minimal technical competence before being allowed to get one.
Other suggestions 'out there' have been to make sure that any petition is in a format that the FCC is used to (I believe druidhillsradio suggested that at Part15.us as well), and that makes sense.
So there's no point in ignoring the fact that a lot of this has been thought of, tried and rejected by the FCC many times over. I believe we may may have a few unique ideas, but it's all going to reside in how the petition is written - it has to be focused on what the FCC wants to see.
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neil
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Post by neil on Mar 18, 2016 0:24:51 GMT -7
Forgive me if I brainstorm a bit but I think we are at that stage. Some possibly viable ideas have been presented which include licensing of a new radio service. We have all seen posts about our desire to experiment, to serve the community, to operate responsibly, and not to cause interference. There is already a radio service which shares these characteristics and that is Amateur Radio.
I know that many of us are hams and I would ask "With your ability to run lots of poser and talk around the world what are you doing messing with Part 15 stuff?" Well, I do it because I like it, it is fun.
A major distinction between Part 15 activity and ham radio is that ham radio operators are not allowed to broadcast and are not allowed to use music. Part 15 has no such restrictions.
Here's a suggestion. Petition the FCC to expand the available Amateur Radio bands to those 2 up 2 down mentioned and allow for broadcasting and music in these two bands. Those who want to participate would then need to get an Amateur Radio license which is not really that difficult if you can demonstrate by testing that you know basic radio technology and fundamentals. Nothing gets changed regarding the ham bands without the support of the ARRL but, again, there are many hams here and on other forums for Part 15 indicating interest in both activities and there may be more support from that organization than expected, especially if it doesn't take away from existing ham bands.
Details on how to prevent food fights over available bandwidth and interference between users on shared frequencies with continuous transmission would need to be worked out, perhaps via power limitations.
Sleep on it, kick it around a bit, but give it some thought.
Neil
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Post by Druid Hills Radio on Mar 18, 2016 6:54:19 GMT -7
I believe it's RMS now? I don't think we should touch the existing Part 15 rules - just add to them. I know that Canada for a while only allowed its BETS-1 field strength limits on a few channels at the top & bottom of the FM band to limit interference - hobbyists using the rest of the band had to use RSS-210 (i.e., Part 15) field strength limits. So there is sort-of precedent here from elsewhere in addition to New Zealand. If Rich joins in, or even if he doesn't, it would be interesting, no matter what is eventually decided, to do some simulations using NEC on those frequencies to see the field strength contours (as well as potential adjacent channel interference) with that kind of power & ideal antennas (which would give you maximums). As for shortwave, it's an open question in my mind if the ITU had to be involved with what would be a domestic shortwave service. I know that in the amateur radio world, a couple of watts with CW can get you great distances, but we're talking here about AM, SSB and potentially things like DSB. We could even eliminate digital modes from the equation. We're going to have to get someone in who has some experience in dealing with shortwave licensing. So.....I emailed Allen Weiner from WBCQ and this is the email chain: The ITU sets up bands for broadcasting as applied by various countries. All voluntary. Basically everyone does what they want, kind of. Like there is no broadcasting on longwave here in the US. Why not? Go figure. All politics and confusing. They meet every few years to hash it out. FCC represents US. Check on line for more info. Allan On Fri, Mar 18, 2016 at 9:39 AM, John Mouw wrote: Good Morning Allan, I am involved with a group looking to expand experimentation broadcasting in the shortwave bands. The subject of ITU approval besides the FCC came up. Can you elaborate on this subject since you are an advocate of this very thing? Regards, John
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Post by Variety 1560 AM on Mar 18, 2016 7:11:51 GMT -7
i still think something like the 2 up 2 down approach or the 1710-1780 approach is most doable. i believe it is the path of least resistance since no one has any real vested interest in those ranges and apparently no ITU issues.
i'm thinking and have been thinking all along of maybe 100mW RMS TPO (500mW PEP) and either no antenna restrictions at all or antenna restrictions similar to TIS, 15 meter height, loading coil and top hats allowed and don't count against the 15 meters.
just look at what 100mW input and a rangemaster 15 meters up is capable of doing.
i think even on those frequencies though we would likely not get much beyond what is already allowed, so changing the input to rms output and loosening of the antenna restrictions might be doable.
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Forget FM
Mar 18, 2016 8:56:47 GMT -7
via mobile
Post by mighty1650 on Mar 18, 2016 8:56:47 GMT -7
I think Neil hit the nail on the head here. The FCC is really not going to like the idea of upping the power to people who have little knowledge of RF. Making this a part of amateur radio is a fantastic idea.
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Post by Variety 1560 AM on Mar 18, 2016 9:05:54 GMT -7
i suggested that long ago too, but if you make it part of amatuer radio it will likely be mandated as two way communications, beacons and no music allowed.
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