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Greg_E posted on another thread about this topic. I thought it proper to begin a new thread since it is a bit off the original theme of the other thread.
Greg_E wrote
[quote]I would be all for a licensed 1 watt station, kind of like they allow in most of Europe (and maybe Canada). One watt on the hill where I am would give me a pretty decent area.[/quote]
Greg_E posted on another thread about this topic. I thought it proper to begin a new thread since it is a bit off the original theme of the other thread.
Greg_E wrote
[quote]I would be all for a licensed 1 watt station, kind of like they allow in most of Europe (and maybe Canada). One watt on the hill where I am would give me a pretty decent area.[/quote]
Let’s start this with a discussion of the potential range for a 1 watt AM service. If the claims of some posters of achieving 1 to 3 miles range with a 100 mW. AM system are accurate then I predict the range will be increased by the square root of 1watt/100 milliwatts. Thus the range would be about 3.16 times the present range or about 3.16 to 9.5 miles. Keep in mind that the baseline here is reported ranges of 1 to 3 miles under receiving conditions which are not known to me.
Use your own numbers here. Take the usable range that you know you can provide to the typical home listener and multiply that by 3.16. Is that range gain sufficient for you to submit to licensing, competetion for frequencies, interference arbitration, equipment restrictions, and other issues that you don’t have to deal with under the current rules?
Looking forward to some good comments about this.
Neil
Total posts : 45366Actually, I was thinking about 1 watt for FM. Without saying too much, I know it would go a long way at my location (2 watts would be better). But I would be willing to go 1 watt (transmit) AM too. When things slow down at work, I intend to look into a licensed AM, hopefully they will be willing to grant us a reduced power license. Something like the TIS systems would be just fine, even with a shorter antenna. Lets face facts, having a great tall antenna would be perfect, but how many people really have the realestate to erect one.
Total posts : 45366This is just off the cuff as were the previous comments. First of all, that 1 to 3 miles with 100 mw is generally a very secondary signal in a car. Nothing that would be at all readable in a home. I’ve never gotten more than the few blocks that Rich predicted a long time ago with the SSTRAN and outside SSTRAN antenna, or the Ramsey AM 25. I have experimented with 1 watt and find I’ve gotten just another block or so with a primary signal (about 4 blocks.) This, of course, is AM. I’ve experimented with a 1 watt FM transmitter and a simple dipole antenna on the roof in flat terrain, and go almost 2 miles with a nice clear, clean signal. Of course, the FCC is not about to give up any of its money making FM band to us “crazy” hobby broadcasters. AM is the way to go if we’re to expect a few crumbs and less interference from them, yet AM has so many variables towards obtaining a well propogated signal compared to FM. Jim B
Total posts : 45366I think Jim nailed it, we should just give up on FM and work for AM to be LP type community broadcasting.
We seem to be reliably making it about 1/4 mile with the allowed 100 mw.
Total posts : 45366Greg and all,
Sorry, I just assumed you were talking about AM. A few questions which probably don’t have a right or wrong answer but I would be interested in your thoughts. What range do you think you could achieve with 1 watt on FM and be thoughtful because the range depends on more than just the power? Would this meet the needs of the micro broadcasters as well as the intended audience?
Jim added some good information. If we just limit the talk to AM for now then I would agree with his comments about usable range. Forty five years ago I ran a tube part 15 transmitter and verified an in home listener who was about 300 feet from my transmitter. Today, I use a SSTRAN unit with an indoor antenna and my car radio range is about two tenths (1000 feet) of a mile. If Jim’s range estimates are realistic, and I believe they are, then we can get an idea of what one watt on AM would do.
SaGr reports 1/4 mile with 100 mW. and by my formula this would extend to .79 miles with 1 watt. Thanks for the input.
Neil
Total posts : 45366I would really like to have a LPFM where I am at. Even if there was a window I would have a problem find a frequency to be on. The sad thing is that I have alot of support for it, from the the city council in my town, the school system and even merchants that would help support it. Alot of LPFM have trouble getting support. I have decided that if I want to do any community broadcasting it will have to be a part 15 or something else in the AM band. I have been involved with some LPFM and have seen what no public support can do to these stations and it is ashame. It is also a shame to watch CP expire for other LPFM for either lack of support or knowledge. This especially hurts when I know I have a community that would go all out to support one. I even have a community paper that talked to me about selling combo ads. I would really appreciate all of your assitance I can get in this project. I have heard people talk about multiple transmitters and more. I would love to make this opportunity I have here a success with the right help. Let me know what everyone one thinks, I am open to any suggestion.
Total posts : 45366Northernlightsmedia,
It is nice that you seem to have community support for starting a broadcast station yet unfortunate that you face an uphill battle. You mentioned a CP that expired and I wonder why this would happen if support was available.
In 1962 (yes, I am gray and proud of it) I was the photographer responsible for all pictures for our high school yearbook. One of the things I did was travel to take photos for the paid ads. There was a new FM station on the air in Eaton, Ohio, WCTM, and it was assignment to enter their building to try to sell an ad. Upon doing so, I met a wonderful man, Stan Coning. I don’t remember if I made the sale but here we are many years later long after I left that community and I found an article about him and his stations. If you take some time to read the report on the link below you will no doubt see the “community broadcaster” spirit that he had and which it may take to achieve what you want to do.
http://www.fybush.com/site-021205.html
Neil
Total posts : 45366I was talking about CP issued during the first round of LPFM being issued and some expiring. I am familar with the story in Eaton. I love a good challenge so I am going to see what I can do. I have been involved in the radio industry for over 25 years and I am tired of the way it is going. I would love to just cover rural town of 300 plus out into the rual counrty. I would be satisfied with that! I have the studio equipment just have to get the signal out. i am hoping to get some great input here on the best way to do a Part 15 and get the most range. I have heard alot of people say Part 15 is not to used for this, but what other way. The FCC only put out thr LPFM is help diminsh the ever increasing people who were pirates or were going to become pirates. The whole program is a joke in their eyes and they could care less about it beleive I know. Small communities like mine are in need of a radio station that serves their needs not the need of a corporation. I am not a fan of satelite radio either but I love that it is forcing the big radio corporations to spend money on HD Radio (which is another joke) but when you have millions of dollars might as well waste some (try giving some to the poor). I ran out and bought an HD radio to see about the what everybody is calling the next biggest thing in radio. Just another way for corporation radio to get more for the buck. Now instead of having one homoginized station they can no have three. Sure alot of them are running commercial free right now. But t will not last the only reason it is commerial free now is because they know no one is listening. The sound is a little better, a lot of dead spots where the signal goes out for no apparent reason, even 3 miles from their towers. Enough of my rant. I would accept assitance of any of you techical experienced people out there.
Total posts : 45366[quote=northernlightsmedia]It is also a shame to watch CP expire for other LPFM for either lack of support or knowledge. This especially hurts when I know I have a community that would go all out to support one. I even have a community paper that talked to me about selling combo ads.[/quote]
According to the FCC info at http://www.fcc.gov/mb/audio/nature.html, it looks like selling ads for broadcast on LPFM isn’t permitted. LPFM stations are defined as non-commercial operations.
Here is a clip from the FCC document linked above.
[quote=The FCC]We reiterate that acknowledgements should be made for identification purposes only and should not promote the contributor’s products, services, or company. For example, logos or logograms used by corporations or businesses are permitted so long as they do not contain comparative or qualitative descriptions of the donor’s products or services. Similarly, company slogans which contain general product-line descriptions are acceptable if not designed to be promotional in nature. Visual depictions of specific products are permissible. We also believe that the inclusion of a telephone number in an acknowledgement is within these general guidelines and, therefore permissible.
Several examples of announcements that would clearly violate the rule may be helpful:
A. Announcements containing price information are not permissible. This would include any announcement of interest rate information or other indication of savings or value associated with the product. An example of such an announcement is:
— “7.7% interest rate available now.”B. Announcements containing a call to action are not permissible. Examples of such announcements are:
— “Stop by our showroom to see a model”;
— “Try product X next time you buy oil.”C. Announcements containing an inducement to buy, sell, rent, or lease are not permissible. Examples of such announcements are:
— “Six months’ free service”;
— “A bonus available this week”;
— “Special gift for the first 50 visitors.” [/quote]
Total posts : 45366It’s always been my understanding that advertising was a no-no but underwriting is OK. The difference being no comparative product description or direct “Buy our product” wording.
Total posts : 45366Sorry should have said underwiting. This can be done as long as rules are followed> the newspaper would have an ad and we can say for more information go to our website or there website and then a direction to an ad in the newspaper. Siple Undewriting announcements can be down. As long as call to actions and prices are not metion. “Thanks to John Smith Automotive at 1234 N Main Street in Anywhere USA. 937.224.0501 . More information about our gracious underwriters is at our website at http://www.wxyzradio.com. The web site then can make reference to anything it wants like. See John Smiths ad in the Daily Gazzette for specials.
There is always a creative way to do it. A station in Pennsylvania called the switch even has it’s own newspaper and is selling combo underwritng with newspaper ads. I guess I should have said Underwritng just assumed everyone knew what I talking about. I have woirked for several Full power non-coms. What is the rule with part 15 since they are unlicensed?
Total posts : 45366Back to the FM range question, I can’t say as I’ve done this, but someone else has and told me about it. With a “cheap” omni antenna (a V with an inverted V rotated 90 degrees, about 3db gain) up on a hill and a 10 watt capable transmitter running at somewhere between 1 and 2 watts (low power setting is 0-2 watts), the range was many miles (at least 5 miles). Antenna location is 50 feet off the ground, with a building that sits up on a hill.
The transmitter was connected through about 100 feet of RG-8, and the transmitter was brand new, and built from a reliable company. The company that built the tranmitter also built the antenna, and the antenna tower, and ran the coax cable. Audio was fed through an Inovonics stereo generator into the tranmitter. I tested this same rig at minimum power on the indicator, and it gave much too much range compared to a part 15 FM rig. That range was our complete campus, and the power indicated was less than .25 watts on the meter. The low end of the power meter was a little tough to determine. Our campus is about a quarter mile in diameter, and the radio used for that last bit of testing was ultra cheap with poor reception (it cost a whole $5 new).
So one watt with a raised 0db gain omni antenna should give a pretty good range depending on location. I think running half a watt into what we have would be a good start, and give us a nice strong FM stereo signal over the entire campus, and some of the surrounding housing where many of our students live. That would be about .75 watt effective power, and agian, it would be a start.
I’d love to do more testing, but after I found that the minimum power output was too much, I removed the transmitter and put it in storage just to prevent it from being used again.
Total posts : 45366Greg,
Your data and experience with the transmiters and antenna you mentioned sound realistic, yet still would not be legal under part 15 for FM.
I think there are two workable options for your campus radio project. The first is what is called carrier current AM which is allowed under part 15 for college and educational campi. In general, each building (probably the dorms where the most people are) would have its own transmitter which feeds the RF into the power line. Each building is on its own transformer and since the RF will not pass through transformers each building will need its own transmitter.
I was the Chief Engineer for WFIB, the University of Cincinnati campus carrier current station years back and we had at least six transmitters distributed in the dorms. The audio was fed by leased phone lines. This was not cheap and was funded through the college student activity fund, but it did work well. Several of our “talent” folks went on to real radio careers after graduation and a couple of our engineering students went on to build military and satellite radios.
The transmitters were tube type, several home built (one by me) and were in the 10 to 25 watt class. The one I built was a 25 watt class C plate modulated unit. The big challenge was getting 12.5 watts of clean audio from the modulator. The RF was coupled to the 120 volt power system with a L-C matching network. This produced a strong signal in the buildings which could barely be heard outside. Since the signals did not radiate far and were isolated by the power distribution transformers we could operate all of them on the same frequency. This was great because one frequency could be advertised campus wide and the station had many listeners. The programming originated in studios at the Cincinnati College Conservatory of Music and operated 24/7.
After I left, some genius thought it would be a good idea to string a wire between the light poles at the stadium and connect the 25 watt transmitter to this to broadcast. The FCC monitoring station in Washington Court House, OH. forty or so miles away heard this and shut them down completely for about a year, including the carrier current operatons. Moral…don’t go on the air with high power.
The second thing to look into is a system which was linked from this board but I cannot find it. It was a broadcast service intended for retirement apartment buildings and provides programming for retired people. From what I read, I think they are using a “leaky coax” system on FM (maybe not the broadcast band) which would seem to be legal as long as the field strength limits are met. The radiator seems to be leaky coax installed along the hallways above the ceiling. The idea would be that all the living units are within a few tens of feet of the coax so a very low field strength would serve the potential listeners very well. Since part 15 only limits the field strength at 3 m from the antenna and doesn’t specify the antenna I think this could be compliant. The catch would be to document that the field strength was within limits, but perhaps if the power was adjusted to limit the range to less than 200 feet from the coax it would be compliant. I would run this by a FCC engineer before spending much money though.
AM carrier current for campus use is well established, the FM system I mentioned is partly just my imagination but I suggest you should pursue these rather than a central high power transmitter.
Neil
Total posts : 45366My small town is about as big as your campus so I am looking at some of the same range. WE are located on the second highest spot in Ohio and I have the permission to use the watertower for an antenna site or the school has a 200 foot tower that is not being used. Also each one of the grade schools. One to the north of town about 10 miles, one to the south about 2 miles and then the Jr High which is in the middle of town all have towers of 150 to 200. Could multiple transmitters be put at each area and then audio sent via internet.
Total posts : 45366I’ve got the boss convince to think abot an SStran AMT3000 and the antenna from their page. All I need to do now is price out the antenna components so we know exactly what it will cost. Then order everything and build it. I’m also going to start looking into lower power licensed AM, and see if there is any way to get the fcc to give us a waiver to run at lower power. In the case against Radio Free Berkley, the FCC states that he never requested getting a waiver to run at lower power, and that he was (obviously) never denied a lower power license. So that gives hope that the FCC might be open to allowing certain places to operate outside of the current full or LP rules. In other words having a good old class D FM or similar for the AM side. Another college not too far from here has an old 8 watt AM station. It as been around for many years, and was probably grandfathered in with that class.
Once upon a time our college had carrier current on all the lightpole power runs. I’m not sure what happened to it, but it hasn’t worked in more than 20 years. Now it would be much harder to implement because just about every building has it’s own tranformer, and I think the light poles have been changed too. From what the reasonable ranges are from part 15 AM, I think we will be OK. And then I’ll think about making the area larger with multiple transmitters.
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