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Total posts : 45366but why would that sabotage the FM band? There has been successful test elsewhere in which have proven that power with 1 watt and even less than 10 watts would not cost much interference if any at all provided that the operator practices good engineering skills and uses common sense.
we all know that Canada has these 1 watt services that they call announcement transmitter and yet they don’t seem to interfere with anything. I think the greater reason for all of this is again to try and keep the competition at Bay. I’m sorry I’m not trying to be disgusting here but this is the real deal.
If you have good filtering on your transmitter and you’re transmitting from inside your home again with a telescopic antenna even if one was to use 7 watts and I’m saying even if you were too we’re talking hypothetical here the most you’re going to travel from with inside your home is a good 2 miles at best. This of course is without any type of trees to block you. The house itself is a major attenuator. Now outside the house we know that it would take far less power than 7 watts to make a 2 mile range. You might be able to do it with one lot or considerably less. Again it depends on how high you are above sea level and obstructions around you because FM is line of sight. That being said I feel that field strength alone isn’t unfair disadvantage to try and limit someone. If you’re going to go by field strength it should be from the borders of your property not the antenna of your transmitter. Or even be fair enough to see from the outside of the house that you live in or the studio that you’re transmitting from.
I get some people’s feelings were hurt when some Wise Guy decided to blast Howard Stern from his satellite receiver to his FM transmitter and at the time it was traveling pretty darn far. But I think the rush to spoil it for everyone was far too great. That individual or those type of individuals should be dealt with on a case-by-case basis I don’t believe that every single hobbyist wood disobey or be so abrasive to do exactly the same thing.
speaking speaking of interference I think the FCC needs to pay attention to those commercial stations in which overdrive their base and bleed several frequencies of the FM dial. I’m not just talking about a few adjacent channels in certain areas where mr. Bruce was talking about there are certain commercial stations that are really taxing It to the Limit. But yet there still on the air and still causing these same problems.
again I appreciate and can accept that we need to be careful of interference however when the playing cards have been laid out on the table and proof has been administered by various different study groups other than one hobbyist that it is not always bad to be able to transmit up to a mile maybe two I think it needs to be looked at and again it should be on a location type basis. Not everyone is going to be able to use FM and not everyone can use AM. it’s going to depend on where you live.
mr. Bruce is right though because I think a lot of people have a Miss concept of range where everyone believes that if one person can get one mile on a particular transmitter using a particular antenna you should be able to get the same thing where you live. But you have people like Barry who live in the mountains it might come down to the fact that for his location it could take twice or three times the power to get that very same distance. As I have discussed from various reports that I got some people talked about having a 50 watt transmitter and yet couldn’t transmit to any listeners who called his station Beyond two to three miles. I’m thinking what? Surely to God with 50 Watts you should get 10 20 30 miles right? Well I’ve learned that that is actually wrong. Then again I’ve seen reports where someone with a 300 milliwatt transmitter could go one to two miles or as someone with 1 watt transmitter struggled to get 2 Miles. What’s up with that picture? So I think field strength is not always the best way to go it is an unfair disadvantage to the Hobby broadcaster. If we’re going to do it fair there has to be some other method based on where they are broadcasting from and everyone should have an equal slice of the pie. keep in mind that technology keep in mind that technology is getting better and better there for the transmitters could be made better and better and able to block the interference.
Another case in point and this may prove my concept that it’s not all about interference but more about trying to stifle the competition. Look at the Murs Radio Service it’s a two-way radio service and which is in the public service band pretty close to the ham radio band which we call 2 meters and very close to pagers and even in the same vicinity band of the Weather Service broadcast yes you are allowed such power that your two ways radio can go at least 2 miles sometimes further. Now keep in mind that the aviation frequencies are just as close if not closer to the Murs Radio Service as it is to FM Broadcasting. Murs still has to worry about second harmonic 3rd harmonic and so on type interference. So the answer is right there it’s pretty much in your face it’s not about interference alone there are other factors here that’s why the laws and why we make them what they are. But if Donald Trump comes and changes things and makes it better for us hobby radio broadcasters which I am sure will happen we should think about this and how we can help each other not cause interference once he comes to the podium and tells the FCC that they are fired at that point it is open season for us hobby radio broadcasters so we need to help each other now for that day. we need to be prepared and need to teach each other good practice. That way when he does this and people do get these transmitters don’t know how to prevent any type of problems.
yes I am over optimistic but again I predicted that the phone company would have unlimited free long distance and look what happened it did take place. Now I’m predicting that hobby broadcasting will be available at distances far greater than what we have now.
Total posts : 45366I agree with Rich, and this is one of the reasons why I believe that increasing FM field strength for frequencies with existing licensed stations is just not going to fly, i.e., the current FM band.
With licensed stations, the FCC knows where each is located, and their power. As Rich states, they can then calculate the interference levels. They have no idea where someone who purchases a Part 15 transmitter will broadcast. With the FM rules the way they are, the FCC does not have to worry about anyone complying with those rules generating interference no matter where they are, as the signal is so puny.
It’s certainly true that in certain areas you can run much higher power than Part 15 allows, and not interfere with anyone. It’s also true that in many areas you can’t. And how do you know, short of owning expensive test equipment, or having the requisite knowledge and software and data to perform inteference simulations? Driving around and listening for an empty channel just doesn’t cut it. Most people don’t even know the basic specifications of their car receivers, such as sensitivity.
And again, as Rich says, the FCC assigns frequencies to licensed stations based on their existing knowledge. If there is an empty channel, it will likely get assigned in the future, with the expectation that there isn’t anybody else broadcasting on it.
There are really only a couple of options to get that increased field strength, in my opinion:
1) Keep things unlicensed, but put these stations on Whitespace frequencies, working within the proposed Whitespace rules (including automatically checking a database for existing licensed stations in the area to reduce/eliminate potential interference) or, and this preferable,
2) Introduce a new, low power (community) licensed service that is relatively easy to get, and relatively inexpensive. Given that the FM bands are already overcrowded, you would still have to move these low powered licensed stations outside the band – they could be moved to Whitespace frequencies, and then they would become the ones protected against interference by the proposed Whitespace rules (they’d go into the Whitespace database).
I understand that most Whitespace frequencies, with the exception of 87.5 & 87.7, cannot currently easily be received by standard FM radios in North America. But beggars can’t be choosers. And if there is interesting stuff to listen to on those frequencies, that could change very quickly.
It’s kind of a chicken or egg problem. Which comes first?
Anyway, just my thoughts.
Total posts : 45366Canada does NOT allow 1 watt unlicensed transmitters. They DO allow up to 1 watt LICENSED transmitters to be used on private property or certain types of public areas (such as parks or malls), as long as the field strength is less than 100uv at the property boundaries (thus controlling potential inteference).
Both the CRTC and Industry Canada have determined that such a transmitter is NOT a broadcasting venture (a broadcasting venture is defined as a transmission that can be listened to by a member of the general public – if it’s on private property, by definition, the general public is not listening). That is important, because it means that a CRTC license is not required – only an Industry Canada license, which is relatively easy and inexpensive.
So you really can’t look to Canada as proof that 1 watt won’t cause interference.
And by itself, with no other qualifying data, that statement is really quite silly. Of course 1 watt can cause interference. It also might not.
Given the right circumstances, 1 watt can be received (according to Johny Cole of New Zealand, where he runs just that) up to 20 kilometers away on a good car radio at the top of a hill, line of sight to his antenna.
In other circumstances, it might only go a few thousand feet.
The only way to know if you’re causing interference is to know the protected field strength boundaries of each licensed radio station in your area, and then to determine your field strength at those boundaries. That will take expensive test equipment, or lots of data and extensive simulation. As I posted previously, driving around in a car, listening for an empty channel, just doesn’t do it.
Total posts : 45366At least for me. I was running about 12mW 10 years ago. That gave me a solid 1/4 mile. Could make it out a half mile with some picket fencing. Once LPFM started to go down the toilet (LP10, anyone) the idea of being over the 250uV level was out the window for me. Seemed the idea of broadcasting Part 15 was going to stay the way it was. I think the FCC has shown some restraint by not banning ALL Part 15 transmitters. There seems to be some wiggle room for those who don’t abuse the air waves and show some electronic prowess.
Maybe some frequecies below 87.5 with a power limit around 1mW? How about something in the 900 Mhz range? All depends on how much radio spectrum is up for grabs.
Total posts : 45366Sorry for continuing to harp on this, but the proposed Whitespace rules are ideal for some sort of enhanced local community broadcasting.
I see no reason why a broadcast transmitter couldn’t be certified for use in this band (86-88 Mhz) – to meet the rules, the transmitter would have to have some mechanism of determining it’s geolocation, and then it would go into the Whitespace database to see if there are any protected, licensed services close by. The appropriate power level, based on that check, would then be used (i.e., 0 up to 1 watt).
To me, the effort to convince the FCC to allow broadcasting in this Whitespace band would be far less than to attempt to convince them to allow more power in the current FM band.
Total posts : 45366Just to add to Artisan’s post about Canada,
@TheLegacy, The I watt we are allowed that is licenced(RSS-123) is for a certain length of time(usually) like an event for example and not for all the time broadcasting.
This not to be confused with low power “announcement” which is a different catagory….BETS-1 that’s not limited to any special event or time frame and is unlicensed, with few restrictions on programming.
Oh yes, @Thelegacy….As Artisan pointed out your signal strength with RSS-123 can’t be more than 100uV/M@30meters past the primeter of your “event’ coverage so if your property or event area isn’t that large you can’t go to 1 watt because you will be over the allowed field strength at the perimeter…..so you can’t always have 1 watt!
I hope you now have a better understanding if how it is here.
Mark
Total posts : 45366I like the scan/database idea. And 86-8Mhz. SOME Radios well receive 87.5 and 87.7 Mhz and a waterproof transmitter would fit the bill.
Total posts : 45366Well I have several stereos here, where the digital display tuner goes down to 88.5MHz, so I am sure there are other tuners out there that do the same thing. So perhaps opening up that channel for SLPFM might be acceptable.
But Troy is correct about the stations near me, both 106.5 and 107.7 clogging up the entire upper FM band from 106.3 up to 107.9MHz with channel splatter as far as 7 miles away, you have no clue, but then again, both stations are owned by John Fuller, who also owns Red Wolf Broadcasting and there’s no other stations close enough to claim interference from those two signals. At 25,000 Watts WBMW 106.5 is Eastern Connecticut’s most powerful radio station and WWRX 107.7, well they push mega bass playing urban hip-hop music, so that splatters pretty good as well. They (WWRX) are supposed to be moving their tower to Branford R.I. but it is still in North Stonington CT, but licensed as Branford R.I. just the same, go figure.
Bruce.
Total posts : 45366But….if the unlicenced even in the FM band became licenced with a written test maybe so you can show you have some knowledge about what you are doing and know the rules, and cheap like $100 a year for example then the FCC would know you exist and can be on their radar…this could go along with a little more field strength?
But if no radio will get where you can broadcast it’s no good. 87.5, 87.7 and 87.9 would be good for such a service. Not to sound like a broken record but if the FM band was like everywhere else including New Zealand there would be space for the commercial stations and us.
Mark
Total posts : 45366DAMN I made a mistake in post #9, I said 88.5 was my lowest FM radio channel that my digital tuners went down to, I MEANT TO SAY 87.5MHz NOT 88.5!!!!!!!! It’s too late to correct that error now, but it should have said 87.5MHz.
My stereo FM tuners tunes 87.5, 87.7 and 87.9MHz and up into the regular FM band from 88.1 to 107.9MHz.
Bruce.
Total posts : 45366I thought 87.5 was what you meant. And your antenna would be a little longer.
Total posts : 45366Ok, then license low-low-power. Done. Problem solved.
Total posts : 45366I agree with that it is the separate service that I am proposing on the website that is part of my signature below. However we need more than armchair Warriors to get it done.
I see others who are making the same statements that they would like to change things. A spokesperson for the New Radio Revolution has already started talks with FCC agents. If we had a large following I believe we could actually make it happenen.
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Opening a new thread as suggested here on November 25, 2016 – 18:38 by ArtisanRadio (thanks):
Previously … Again I’m sorry I let this stuff get to me but I think sometimes we need that reality check to keep us together as a Hobby Broadcaster. …
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[Edit by radio8z: For those wondering which thread is referenced herein (as was I) it is here:
http://www.part15.us/forum/part15-forums/general-discussion/funny-how-people-cant-see-forest-trees#comment-49126
]
The reality check for Part 15 FM that appears to be misunderstood by the author of Reply 18 of this thread is that FCC §15.239 limits the field intensity 3 meters away from its transmit antenna to 250 µV/m for good reason.
Namely, that then the FCC can predict the peak interference levels from such unlicensed setups that are, or may become objectionable within the normal and authorized coverage areas of present _and future_ licensed users of the FM broadcast band.
That is one of the mandates and functions of the FCC.
The operators/proponents of unlicensed FM broadcast setups who decide on their own, and/or who publically promote that such systems should be (or are) permitted if they don’t interfere with licensed FM stations at a given time/location can sabotage this process.