Pretty soon, FM broadcasting will be phased out in Europe to be replaced by DAB+

This means millions of perfectly functional and high quality FM devices will become obsolete.

With local politicians in my community, we are considering setting up a FM transmitter with a local range that would broadcast the former radio stations on their former frequencies from their Internet versions.

Beyond the question of regulations, we are wondering if some FM transmitters devices allow to broadcast multiple stations (10 to 20) on separate frequencies or if we would need to install a FM transmitter for each station.

Thanks

 

Pretty soon, FM broadcasting will be phased out in Europe to be replaced by DAB+

This means millions of perfectly functional and high quality FM devices will become obsolete.

With local politicians in my community, we are considering setting up a FM transmitter with a limited range that would broadcast the former radio stations on their former frequencies using their Internet versions.

Beyond the question of regulations, we are wondering if some FM transmitters devices allow to broadcast multiple stations (10 to 20) on different frequencies or if we would need to buy and install a FM transmitter for each station.

Thanks

Hi D,
You will need specialised equipment, that has been passed by the authorites, and a licence, which is not an easy project, good luck.
C

 

The available RF spectrum will be quickly repurposed, rendering the radios 100% landfill.

 

Pretty soon, FM broadcasting will be phased out in Europe to be replaced by DAB+

This means millions of perfectly functional and high quality FM devices will become obsolete.

With local politicians in my community, we are considering setting up a FM transmitter with a local range that would broadcast the former radio stations on their former frequencies from their Internet versions.

Beyond the question of regulations, we are wondering if some FM transmitters devices allow to broadcast multiple stations (10 to 20) on separate frequencies or if we would need to install a FM transmitter for each station.

Thanks

Hi D,
Not what you are asking, but maybe useful?
I have a device that has a 3.5mm jackplug input, that outputs a tunable FM signal, so an MP3 player can be played on a radio.
They have a very low power output perhaps 1-2 mtrs.
I'm not sure how legal they are?
C

 

Beyond the question of regulations...

I don't understand this. From a regulatory perspective, this fails before it starts. This is like saying, "I'd like to fly under my own power, beyond the question of gravity..."

You will not be able to do this without ignoring the law, and the regulators won't ignore you, so...

 

Pretty soon, FM broadcasting will be phased out in Europe to be replaced by DAB+

This means millions of perfectly functional and high quality FM devices will become obsolete.

With local politicians in my community, we are considering setting up a FM transmitter with a local range that would broadcast the former radio stations on their former frequencies from their Internet versions.

Beyond the question of regulations, we are wondering if some FM transmitters devices allow to broadcast multiple stations (10 to 20) on separate frequencies or if we would need to install a FM transmitter for each station.

Thanks

In theory, you could combine all of the signals into a single waveform and broadcast it from a single station. But your transmitter (including the antenna) would have to have a wide enough bandwidth to cover the entire FM spectrum (or at least enough to encompass all of your stations) and do so with enough power so that the portion of the spectrum containing each station has enough power in its share to be viable.

But it's really a moot point. There is a reason that they are phasing it out (as opposed to simply adding DAB+) -- it's because they want/need that spectrum for something else. At that point, your transmitters will interfere with the new use (and, the new use will interfere with your broadcasts). Since the new use would be legal and yours wouldn't, guess who wins in court?

 

I have the (possible mislead) belief that most countries allow low power transmitters on the FM broadcast band, but the regulations vary by country. You might want to check the radio law in your country and decide whether you will be satisfied with the transmitter power limit (Actually specified as field strength rather than power).

If you are not satisfied with the allowed power limits, then as @camerart noted, you will have to apply for a license, and from Bahn's comment you might not be able to obtain such a license. Check your laws, if you enjoy that kind of research (some do).

 

I have the (possible mislead) belief that most countries allow low power transmitters on the FM broadcast band, but the regulations vary by country. You might want to check the radio law in your country and decide whether you will be satisfied with the transmitter power limit (Actually specified as field strength rather than power).

If you are not satisfied with the allowed power limits, then as @camerart noted, you will have to apply for a license, and from Bahn's comment you might not be able to obtain such a license. Check your laws, if you enjoy that kind of research (some do).

This is true, Dick—but the regulations are written specifically to prevent broadcasting. The power limits and restrictions on feed line and antenna are crafted to make such transmitters useful only in a very small area local to the equipment.

 

I spent 6 years building radio stations. (million years ago, more or less) I have seen multiple transmitters connected to one antenna.
Data: All of my FM stations start off with a 10 watt "exciter". Basically a 10W transmitter which drives a 100 to 500W linear amplifier which drives a 30kw amplifier.
I have not done it, but it is my belief that a 1 to 10 watt signals could combined much simplifier than 30kw signals. Then one high power amplifier will amplify all the signals together.

broadcast multiple stations (10 to 20) on separate frequencies

Antennas are built for one frequency, or at least for a small range of frequencies. It would be difficult to get an antenna for all FM frequencies. If I did this I would push all the frequencies together in a small space. Americas = 88 to 108 MHz. I would not want to transmit at 88 and 108 on the same antenna.
The FFC normally spaces the stations at 800khz for any town. (memory is bad) I think when combining to one antenna we spaced the stations much closer. 400khz or 200khz. I remember doing the math and applying for very tight spacing.

Ask questions if you want. I only worked North America. My data is from years ago. We did some very odd things that the FCC normally did not allow but because we understood RF it can be done.
RonS.

 

One other thing: you can mix the signals together(or “combine” them) to drive a single antenna. You may find it helpful to include traps along the antenna do it will tune the whole band at once.

Be conservative about range.

 

There is an additional regulatory/legal concern here as well. Rebroadcasting may run afoul of additional regulations, or the copyright protection of the broadcast content. The stations may object, or copyright holders of content licensed by the stations may object.

 

Digital Audio Broadcasting
Interesting reading.
This post is the same as kicking against "digital TV". Who wants a good picture without snow and, in my case 94 channels.

 

Digital Audio Broadcasting
Interesting reading.
This post is the same as kicking against "digital TV". Who wants a good picture without snow and, in my case 94 channels.

It's been my experience that the "good picture without snow" has been more than a bit of false advertising. The "snow" is just very different -- pixelation, often pretty extreme. A lot of pauses and hangs while things rebuffer. Annoying delays with every channel change while it gathers enough data to start displaying a picture.

 

It's been my experience that the "good picture without snow" has been more than a bit of false advertising. The "snow" is just very different -- pixelation, often pretty extreme. A lot of pauses and hangs while things rebuffer. Annoying delays with every channel change while it gathers enough data to start displaying a picture.

You just need a good antenna.