Hello! I am curretly working on a project to make a FM radio station to cover the largest area possible but like $150 or less. I have found a transmitter Here but it only has a range of about 150ft and i need at least a mile. I've seen a few antennas o Amazon but most of them are FM receiver antennas. Will they work. I found a 1/4 wave antenna on Amazn for pretty cheap here and it looks good but my transmitter is .5w and the antenna is at keast 5w. is there any way to amplify the output? Also i find these omni-directional antennas for cheap here, will they work? Is there ant DIY stuff i can do? will these mount on the roof of my house? I live in an tree-infested area, will that limit my range? i am planning to broadcast somwhere near 85mhz, is there anything special i need to do this?
Thanks. Sorry i'm such a noob.
Thanks. Sorry i'm such a noob.
Have you consulted the FCC about this? They might have some comments for you.
https://www.fcc.gov/media/radio/low-power-radio-general-information
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The transmitter is only half a watt. If you want more distance it would be easier to get a transmitter with more output. I saw a few on amazon. The antenna you found can handle up to 100 watts from your transmitter it will work fine with any transmitter below that.
Take a look on ebay... just found this one...
5W / 15W PLL FM Transmitter Radio Stereo Station Wireless Broadcast+TNC Antenna | eBay
3dB Powerful 1/4 Wavelength 88-108MHz GP TNC Antenna for Radio FM Transmitter YS | eBay
5W / 15W PLL FM Transmitter Radio Stereo Station Wireless Broadcast+TNC Antenna | eBay
3dB Powerful 1/4 Wavelength 88-108MHz GP TNC Antenna for Radio FM Transmitter YS | eBay
You want to broadcast on 85Mhz. This is probably illegal. The Commercial FM band starts at 88.1? Whom are you planning on transmitting to?
Look on the web for Low Power FM transmitting requirements and you should check on the FCC website - As I remember, years back they relaxed the requirements for the low end of the band - but probably only for "educational purposes".
To get uniform coverage, commercial stations use circularly polarized antennas; otherwise you will be "beaming" your signal in certain directions and not in others. These antenna elements can be stacked (one on top of each other) to get more gain. VHF communication is pretty much "line of sight" so you need to get the antenna up as high as possible.
Charles
Look on the web for Low Power FM transmitting requirements and you should check on the FCC website - As I remember, years back they relaxed the requirements for the low end of the band - but probably only for "educational purposes".
To get uniform coverage, commercial stations use circularly polarized antennas; otherwise you will be "beaming" your signal in certain directions and not in others. These antenna elements can be stacked (one on top of each other) to get more gain. VHF communication is pretty much "line of sight" so you need to get the antenna up as high as possible.
Charles
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in the fcc rules it states that "Unlicensed broadcasts on the FM broadcast band (88 to 108 MHz) are limited to a field strength of 250 µV/m at a distance of 3 meters from the antenna. This is roughly equivalent to 0.01 microwatts.[2] Emissions must be kept within the 88.0 to 108.0 MHz band under Part 15 rules."
I also found that according to radio-locator.com, 95.9 is an open band and its within the 88-108mhz limit. It also mentions a field strength of 0.01 microwatts at 3 meteres. does tis mean that my .5 watt transmitter is to strong? Also i found another 7w transmitter Here. would that also be too high? And what is uV/M?
thanks
I also found that according to radio-locator.com, 95.9 is an open band and its within the 88-108mhz limit. It also mentions a field strength of 0.01 microwatts at 3 meteres. does tis mean that my .5 watt transmitter is to strong? Also i found another 7w transmitter Here. would that also be too high? And what is uV/M?
thanks
from what i understand, i cant have a range ov more thsn 200 feet or risk a fine of $10,000. Also, if i get a license, i have to have at least 100w of power, or "Alternatively, if an effective radiated power of less than 100 watts is sought, the combination of the proposed effective radiated power and antenna height above average terrain must cause the distance to the predicted 1 millivolt per meter (mV/m) contour (or 60 dBu contour) to be greater than 6 km. " Any idea what that means?
That means to have a LICENSED station you either have to have 100W or have a tall enough and properly configured antenna so your lower power can reach 6km or more.
But you are not looking for a licensed station, you want an experimenter situation.
I think the 200 foot limit is pretty clear.
When I was in college at MSU here - 50 some years ago - we had a campus radio network of stations in several dorms. We transmitted on carrier current. That means we drove our signal into the 120v wiring in the buildings. it was strong enough that kids in their rooms could pick us up on their AM radios. For best reception we told them to put their radios next to the lamp cord. Anyway, the rule was our signal could not be receivable beyond 50 feet from the building.
What are you planning to broadcast? If you plan to play commercial music, you may run into licensing that as well. Restaurants have to pay annual fees to play music in their places. We used to operate juke boxes in bars and restaurants, we had to buy annual licenses to play music. You could play your own music - ie music you own the rights to - without paying a license fee.
But you are not looking for a licensed station, you want an experimenter situation.
I think the 200 foot limit is pretty clear.
When I was in college at MSU here - 50 some years ago - we had a campus radio network of stations in several dorms. We transmitted on carrier current. That means we drove our signal into the 120v wiring in the buildings. it was strong enough that kids in their rooms could pick us up on their AM radios. For best reception we told them to put their radios next to the lamp cord. Anyway, the rule was our signal could not be receivable beyond 50 feet from the building.
What are you planning to broadcast? If you plan to play commercial music, you may run into licensing that as well. Restaurants have to pay annual fees to play music in their places. We used to operate juke boxes in bars and restaurants, we had to buy annual licenses to play music. You could play your own music - ie music you own the rights to - without paying a license fee.
Some yahoo here set up his own pirate FM broadcast station, around 92 MHz, IIRC, and was also transmitting a spur on the local ATC approach frequency. His main signal covered about a half mile radius on the ground, but the spur of interest could be heard a long way, ground to air.
It took our local radio club about fifteen minutes to find the transmitter when requested. The FAA or FCC got all the offending equipment. I don't know if they did anything to the guy or not.
Win W5JAG
It took our local radio club about fifteen minutes to find the transmitter when requested. The FAA or FCC got all the offending equipment. I don't know if they did anything to the guy or not.
Win W5JAG
Radio regulation is nearly as old as radio. You think it is fun, but others call it Interference.
There's an aircraft band very close to the FM band. I would _NOT_ set up an illegal FM transmitter at my house for fear of lost aircraft coming down on top of me. Which is what W5JAG said threatened to happen near him. Except the local radio enthusiasts quickly found and reported the offender.
But technical clarity: the transmitting antenna can be a "receiving" antenna, sure, it works both ways. There is no minimum power. There is a maximum power at which the antenna would melt. You can't afford to go there (any bit of wire can take many Watts). On a small budget, it is hard to beat a 30-inch vertical rod in the middle of several feet of chicken-wire as a ground plane. You also see these with four drooping radials for groundplane (more on CB than FM). The length of the radiator is somewhat critical, calculators are online.
Trees are not good, but what you gonna do?
Height is good. But over 20-30' (rooftop) is expensive. At my place I must also obey the FAA obstruction rules (I'm that close to the airport). Down the coast a bit the FAA is asking adjacent land owners to cut-down some 70' trees in an approach path.
Transmitting much past the edge of your property (or into flight-paths) is probably going to get you in trouble.
Trouble can be anything from a warning to $10,000 fine (per incident), and loss of equipment. I do not recall anybody going to jail for pirate broadcasting; but if you refuse to pay the fine that is a new offense with possible jail time.
We are practically at the point of Universal WiFi, nearly more WiFi than radios. You can run an internet radio station.
There's an aircraft band very close to the FM band. I would _NOT_ set up an illegal FM transmitter at my house for fear of lost aircraft coming down on top of me. Which is what W5JAG said threatened to happen near him. Except the local radio enthusiasts quickly found and reported the offender.
But technical clarity: the transmitting antenna can be a "receiving" antenna, sure, it works both ways. There is no minimum power. There is a maximum power at which the antenna would melt. You can't afford to go there (any bit of wire can take many Watts). On a small budget, it is hard to beat a 30-inch vertical rod in the middle of several feet of chicken-wire as a ground plane. You also see these with four drooping radials for groundplane (more on CB than FM). The length of the radiator is somewhat critical, calculators are online.
Trees are not good, but what you gonna do?
Height is good. But over 20-30' (rooftop) is expensive. At my place I must also obey the FAA obstruction rules (I'm that close to the airport). Down the coast a bit the FAA is asking adjacent land owners to cut-down some 70' trees in an approach path.
Transmitting much past the edge of your property (or into flight-paths) is probably going to get you in trouble.
Trouble can be anything from a warning to $10,000 fine (per incident), and loss of equipment. I do not recall anybody going to jail for pirate broadcasting; but if you refuse to pay the fine that is a new offense with possible jail time.
We are practically at the point of Universal WiFi, nearly more WiFi than radios. You can run an internet radio station.
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