Hello all,
Hello all,
Yesterday I learned of my acceptance to a graduate program at a university in my hometown. I have not been on the part 15 airwaves in almost a decade, but I will be moving back to Detroit from my current rural home where webcasting is the only option by August. My family lives in the Central Business District/Downtown neighborhood of Detroit. They live in an apartment building of approximately 30 stories--and are on the 16th floor. The building is very near the center of the district, and the entire district is with a 1.5 mile radius from the building.
Do any of you think it would be practical to attempt to start a part 15 station in such an environment? There are a total of 6,500 residents within these boundaries, 80,000 office workers, and 50,000 visitors each day within this relatively compact area. The housing market grows by about 340 households each year.
How strong/able do you think it would be to get an AM signal out over even part of this area? Interference will probably be ridiculous, at being on the 15th floor in a landscape dominated by 40-73 story buildings certainly won't help, either, in my approximation. My thought was that some sort of webcasting/part 15 combination could work well, or even a talk format with some information for Detroit visitors (area goings-on and the like) could also help listenership, as Marriott operates 1800+ rooms in multiple hotels with .25 miles; I have family members who work with Marriott at one of the locations, so promotional fliers/cards or similar could be feasible.
Not planning to make this a commercial venture, per se, but with web-based content, I am going to go ahead and assume that installing repeaters in the apartments/offices of acquaintances with a simple web link (or some extra money) could allow us to cover all/most of the downtown area where people live.
The Detroit market is certainly saturated, but very little of the broadcasting is neighborhood-specific toward downtown, so such a station could satisfy a niche market, and the webcasting end of would also allow us to produce/run programming that is more accessible to individuals not familiar with Detroit.
Any general ideas--or has anyone else tried anything like this? The last time I was on part 15 I lived in suburbia, so building interference wasn't something I had to consider!
mryan55: How strong/able do you think it would be to get an AM signal out over even part of this area? Interference will probably be ridiculous, at being on the 15th floor in a landscape dominated by 40-73 story buildings certainly won't help, either, in my approximation.
The amount of that area that a legal Part 15 AM could serve well will no doubt be disappointing to you - maybe just a few apartments on the same or adjacent floors to your system. The steel frames of high-rise buildings block medium-wave signals quite well, and radio noise there usually is quite high, also (light dimmers, etc).
Commercial AM broadcast stations strive to produce a field strength of 50 mV/m or more to serve such an area of "urban clutter." That field strength cannot be generated at any useful distance by a Part 15 AM station, even over a clear path.
Sorry to depress you, but that is the physical reality.
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I was editing my post and I blew out my message and the rest of this thread.
That was an accident, I'm just learning this new theme.
Sorry.
Experimental broadcasting for a better tomorrow!
beleive it or not he is in a great position for carrier current. and if he were to start a multi site microwave linked cariier current system that uses neutral loading and synchronization he could easily cover the entire neigborhood w/o a problem and do it better than the local flame thrower.
Thank You,
Rev. Robert P. Chrysafis
Universal Life Ministries
http://www.ulc.org
Moderator Hunterdonfree
http://groups.yahoo.com/group/hunterdonfree
Yes that's true, you could probably cover a large part of that building on the transformer that you are on. I wonder how many different systems make up that building? Now it could be possible that there is a transformer on each floor, but hopefully not.
In most cases loading up the neutrals instead of the hot bypasses transformers. You can cover that whole building with a single Tx.
if you have access you can put a stl on the roof and start setting up sites at each building in your neigborhood using neutral loading.
Thank You,
Rev. Robert P. Chrysafis
Universal Life Ministries
http://www.ulc.org
Moderator Hunterdonfree
http://groups.yahoo.com/group/hunterdonfree
The neutrals are going to be grounded at each floor, isn't this going to cause a problem?
That may or may not be a problem. what needs to be done is you need to get enough of an impedance to load the neutral. this basically amounts to a loop antenna. so you need to ground your tx in a totally different part of the apartment and load the neutral in another location from where the tx ground is. if you get 1 or 2 ohms of impedance you should be able to match it. it takes some experimenting as with all part 15 am operations. it's definately not plug and play.
Thank You,
Rev. Robert P. Chrysafis
Universal Life Ministries
http://www.ulc.org
Moderator Hunterdonfree
http://groups.yahoo.com/group/hunterdonfree
look in the library there is 100's of megabytes of Ebooks on this very subject 🙂
Thank You,
Rev. Robert P. Chrysafis
Universal Life Ministries
http://www.ulc.org
Moderator Hunterdonfree
http://groups.yahoo.com/group/hunterdonfree
Hi,
Congratulations on your acceptance into grad school.
Based on my experiences with part 15 AM in a dormitory when I was a student, the range will be severely limited. When I did this, the range was about 50 to 100 feet inside the building. I recently put an 100 mW. AM station on the air as a demonstration for my communications class in an urban classroom and found similar range. Interference and signal absorbtion were severe.
I also have experience with dormitory carrier current AM. It took a 20 watt AM transmitter to cover one dorm with about 120 rooms and the signal was plagued with hum and interference. It was also expensive to set up and maintain.
There is no harm in trying, but I recommend you don't spend a lot of time and money on this. Do it just for fun and perhaps you and a few nearby neighbors will enjoy the broadcasts.
Neil
My plan was to use Part 15 AM as an extension of the internet broadcasting that I have been doing for the last few years when I wasn't living in Detroit. Since the possibilities for a reasonable range at Part 15 levels on the AM band in Detroit don't seem to be panning out, I think that I will simply put more time and energy into expanding my internet operations and trying to find Part 15 stations that can carry my content in "proven" markets.
Michael P. Ryan
http://www.live365.com/stations/dysfunctionalradio
Well, at least with using Live 365 you are paying the royalties. You might also check out Loud City for a host as they also have a system in place to pay the royalties for you.