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Total posts : 45366That is why it needs to be one step above part 15. Once you start imposing fees you get into Radio for other purposes and fun won’t be in the equation. it will start to lean once again to the rich. It is neighborhood broadcasting at the 1 mile mark for the sole purpose of hobby or entertainment. Those christmas light shows use them and think usiness loop show. Now yes the NAB will wine but if we have our ducks in a row it will make them look irrelevant. We just need data from folks in New Zealand to start. Canada already proves some of the interference concerns can be referred to the data we can get. At least we are getting somewhere.
Total posts : 45366The NAB might be against small operators because they need scapegoats to ignore the poor performance of their member stations.
But what if the NAB got a new idea?
If we can convince the NAB that our programming will actually drive listeners to the licensed stations because our small stations have bad reception. The more power we have, the more listeners we can push over to the NAB stations.
Total posts : 45366I know when we traveled from Michigan to Florida and I was listening to my favorite Album Rock stations back in the 70s when one station was out of range I’d fiddle with the dial till I found another station I liked. If you could convience folks to buy and listen to Radio because you are one of many stations on the FM band it could work. Once your station faded the person may simply change the station rather than head to the Internet in their car. Now even if their were several micro powered stations in a city still people would have to eventually change the channel when that station too faded out. And it could actually get these other stations to look into other artists instead of the same 100-500 songs based on national chart toppers. It sounds great, but getting them to go for it well tht is another matter. However it would be one more thing we could use as a rebuttal.
Total posts : 45366A radio engineer at an FM station once told me that the reason the power level were set way up at 100,000 Watts was influenced by the electronic consumer manufacturers so they could make cheaper and less quality radios.
Total posts : 45366Carl is on to something.
From what I’ve read, one of the biggest issues in radio today is the migration of listeners from AM or FM to other devices and other media types. Rather than being competition for the licensed stations, it is likely that a community station would attract listeners to FM who would not be there otherwise. These listeners. espeically those in cars, would be more likely to tune to other (licensed) FM stations when they moved out of the limited coverage area. Everyone would benefit.
Total posts : 45366For that to work, we’d have to prove that FM needs a boost. I don’t know about where everyone else lives, but in NYC, there’s no shortage of FM support. It would be difficult to convince the NAB, unless there’s something outside the sphere of common knowledge that we can learn.
Total posts : 45366So what your saying is to use the Micro Broadcasting stations as sort of a teaser that would attract more listeners even though during the time they are in range of your station they may not listen to a high power licensed station. Could be very interesting and might make a good point to try and get micro broadcasting stations with more power since the more independent stations there is, the more people will tune around and the more the commercials will reach a wide audience. Not only that but a micro broadcasting is not always gonna play the song you like and you’ll mess with the dial. You’ll probably switch from time to time between the higher power NAB stations and the low power stations. This is also very true to my Radio habits back when FM had more Album Rock stations. So what we’re saying to the NAB is to make lemons into lemonaid as it will help them in the long run if I have what your trying to do right.
Total posts : 45366What would be easier – getting this ball rolling, or just getting the FCC to open up the LPFM application window again?
My original intent was an “in-between”, but after thinking about this for a few days, isn’t this just LPFM, but with lower power? Why not just go legit LPFM?
Total posts : 45366I doubt there will be another LPFM window. Right now it looks like there will either be a free for all translator filing window, or an AM specific filing window. Don’t expect that to happen until Auction 98 is complete and construction permits are issued for build out of those stations.
Auction 98 will do a pretty good shoehorning in a bunch of class A stations where they could fit. Then I would guess a translator window will further fill any holes where any sort of signal could be squeezed in. Add on top of that the possibility for current LPFM’s to increase to 250W and there won’t be room for any more LPFM’s.
Translators used to be boring. They were either used to fill in coverage for an analog station on the FM dial, used to extend coverage of an analog station on the FM dial. Then two things changed. AM stations could use an FM translator to get a signal on the FM dial. Stations with HD 2/3/4 channels could use translators to get the HD channels on the analog FM dial. Suddenly if someone had an AM station or a HD FM station a translator became a FM station without ownership limits. Now that translators are so versatile there will be groups looking for anywhere one can be put in the future translator window. If it is an AM only translator window, expect AM’s to aggressively maximize the translator they apply for. If it is a free for all translator window, expect noncommercial/educational groups to file thousands of applications to shove in a translator anywhere it can be fit, since unless the rules have changed they don’t have to pay fees for filing.
So if you really want community radio, start a petition to let translators originate their own programing and get a translator. A 1W translator is the smallest thing the FCC is likely to license.
On the other hand, if your goal is to keep broadcasting fun be happy with 250uv/[email protected], and be glad there is no public comments out on a proposal to reduce that.
Total posts : 45366I tested a freind’s 500 mW transmitter with a rubber ducky to see how close this prediction came to the actual observed performance. It was amazingly close! To be fair the car radio is a Pioneer Super Tuner with a slightly less than 2 uV sensitivity. The antenna is the standard Ford 31 inch antenna. The signal could be detected in and out but not pleasent at about 1/4 mile. When I turned onto Lee Street (Yellow) it was much better. Very nice when into the green. The transmitter was on a table near a window facing the south.
Total posts : 45366WDCX: That was the range I’m looking @ 1/4 to 1 mile. So actually 500mW may be a little under, but still nice range to probably over 1/10th mile to a Boom Box. What I’d have to do is see of the experimenter would walk outside with a Digital boom box and see how far they could hear the TX. But I’d sort of be happy with that. I’m thinking at a Watt you may get out the same distance 1/4 Mile, but just a little more full quieting at around the same distance. Was this TX on Ground Floor? How far from the window was it Smack Dab on top? The Circular indoor antenna is another thing that interest me into a TNC Connector.
Translator: What about getting a FREE Translator license to translate my station from Internet to FM @ the lowest level 1W. There is a few 1W Transmitters I could get from FMUser. Then the station would have some nice range and I’d probably still have to sign off after 6PM during temperature inversions. But hey its a start.
Total posts : 45366attached to a Ground Plane antenna 10 feet above ground.
Total posts : 45366I searched the FCC database for FM’s operating with less than 1W. I found 3 special temporary authorizations for translators with less than 1W.
K220HD 0.7W
K275AA 0.3W
W288CQ 0.5WThey have some high HAAT’s (heights above average terrain), but they are reasonable heights above ground level.
There is a site, rabbitears.info, that has Longley-Rice maps for TV stations. It also has Longley-Rice maps for a lot of radio stations, if the Application ID is put into the address bar for the URL of a map. Since the maps are geared to DTV, there is some stuff that is not relevant to radio. The color coding of the signal level matches the key on the right of the maps.
I pulled the rabbitears maps for the three ERP<1W translator applications above.
http://www.rabbitears.info/contour.php?appid=1567868&map=Y
http://www.rabbitears.info/contour.php?appid=1576801&map=Y
http://www.rabbitears.info/contour.php?appid=1671341&map=YWith enough height, less than 1 watt can cover a large area. Large enough that convincing the FCC a hypothetical service with more power than part 15 allows but less power than 1W could be hard.
In the above maps, the coverage does not stop at the red, in non-shaded areas reception may still be possible just with more difficulty than in the red shaded areas.
So if someone had a house on a hill taller than the surrounding terrain and they put a 300mW transmitter on a 20’ pole, they could push their signal out 1.5 miles or more (see K275AA’s map), with the potential to cause a signal that could interfere with reception of other stations well beyond that.
Here is a nice discussion of no <1W FM’s from the FCC, and the issues that LPFM 10’s would have faced. http://home.recnet.com/lp-10
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I am all for community radio, but with the current regulatory framework nothing smaller than a LPFM-100 or a translator fed from a HD sub channel or AM is going to get licensed on the FM dial.That leaves 2 FM options:
1. Pirate radio, which is against the spirit of this forum
2. Working with the limited range of 15.239 complaint transmitters on 88.1 to 107.9MHz.I would love to see something change, but the FCC has been burned by every class of FM station operator so I doubt they would even entertain the notion of letting super low power stations on the air. Full power stations optimize or directionalize non directional antennas; translators are fed with STL’s when they need to be feed by over the air means, LPFM operators don’t meet their community obligations, and so on.
If they made the requirement etched into stone “0.5W TPO into a transmission line with 1dB loss into an antenna installed on an exactly 10’ pole operated exactly at the point of license”, at first the people who used the service would follow the rules. Then some would substitute a feed line with less loss. Then some would use a 10.5’ or 11’ pole. Then some would move their antenna from where licensed to higher ground. Pretty soon someone would come out with an amplifier that turned the 0.5W into 1W. And the FCC would have another enforcement headache on their hands. It is human nature to push the rules and see how much can be gotten away with to get just a little more range.
Also by licensing the service, the FCC would need to make sure stations of the service were being decent. Without recordings of what was aired/record keeping by the station, it would be very hard to prove someone did not drop an F-bomb on the air if someone accused the micro station of indecency.
The micro stations would be bottom of the barrel for users of the FM band. Right now if I use a 15.239 compliant FM transmitter as long as no one complains the big stations have no reason to care I exist. Big broadcasters like their market share. If there was a FCC database of where 500mW was being used and on what channels, some of the broadcasters would go looking for interference.The micro broadcaster would need to protect co channel, 1st, 2nd, and 3rd adjacent channels, as well as 10.6/10.8 MHz up/down channels. The micro broadcaster would also need to be aware of mixing products from their frequency and any transmissions of comparable strength in their area. Mixing product calculation becomes exponentially harder as the number of signals being considered goes up.
Total posts : 45366The way I look at it, at the very least, we’re all getting together and learning as we move forward with the thinking surrounding the issue.
Total posts : 45366The field intensity of a given VHF signal at a given receive location on/near the surface of the earth depends on the height and polarization of the transmit antenna, path length, the terrain profile along that path, the effective radiated power (ERP). earth conductivity and other factors.
The graphic below shows the field intensity vs. height above the earth that might be expected for unobstructed paths, and the other conditions shown there.
Note that the field intensity ~2.6 meters and more above the earth at this 1,602-meter distance from this transmit system equals/exceeds what is presently authorized by FCC §15.239 for unlicensed systems, at a distance of just 3 meters.
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