broadcasting fm radio in a factory

twigbog

I work in a pharmaceutical plant and We are currently trying to introduce fm radio headsets for employees to improve working conditions.
There are a few reception blackspots in the plant for radio signal.
I am currently trying to get the signal improved in these areas.
If anyone is familiar with this line of work I would very much appreciate any guidance as to how to go about this.
Would amplifiers improve signal blackspots and,if so,would a broadcasting licence be required for a factory to broadcast fm radio?????

Ruu_Old

Moved from Newbies & FAQ, there are a great deal of forums on boards.ie that could help. I think this one is the closest to your query.

Fuzzy Clam

Any device that does not fit into Comregs definition of an SDR (short range device) on the FM broadcast band, requires a licence. i-trips, for example, fall into this catagory.

One possibility would be to install a radio as close to the blackspot as you can (still getting reception, so preferably high up) and connect an i-trip to the headphone output. You would be stuck with relaying just one station at a time though.

watty

An amplifier at RF won't work as it would "feedback".

You could in theory have your own "station" like collleges and Hospitals do, needs a licence.


You also need a public performance licence and pay royalties if you have a centralised Radio receiver and redistribute that station by any means.

Fuzzy Clam

watty wrote: »

You also need a public performance licence and pay royalties if you have a centralised Radio receiver and redistribute that station by any means.

An i-trip is legal without any licensing.

Public Performance licence may not be required if earphones is used.(?)

Anybody can listen to the radio without a licence at work if nobody else can hear it. i.e. with earphones. Since rebroadcasting music (mp3s etc) on an i-trip is legal, then why not a radio station?

What's the difference if they are listening to an i-trip? If several people are listening to the same i-trip on earphones, does this require a licence?

Watty, do you have a link to a Comreg doc that defines this?

I'm not saying that you're wrong, I just like to see the proof.

watty

It's not personal use.

It's multiple users in a public place.

Ask IRMA. It's not a ComReg issue.

Fuzzy Clam

I think its an IMRO issue.

watty

/me slaps head.
Those are the guys I meant.

Antenna

Some road tunnels (such as the Dublin Port Tunnel and Lee Tunnel) have 'leaky feeder' systems to relay FM radio. Areas of buildings with zero radio reception could also be served by such systems but probably not practical in this case.

you could use (licence exempt) wireless headphones, which operate at 863MHz to relay the most desired stations in blackspot areas. These have a good range from the base station

watty

Yes, but for more than Personal use the IMRO applies. (not a problem, just money)

A passive leaky feed would be legal

Have highish gain vertical polarised aerial pointing at TX sight on roof.

Well screened low loss coax (PF100 sat cable) to indoors and leaky coax in blackspots (maybe even a zero dB gain distribution amp to feed separate areas).

People then use their own FM portables. IMRO and Comreg all bypassed.

Fuzzy Clam

Downside of leaky feeder is the expense.

At least it is from one supplier I was looking at about a month ago. Can't remember the name off hand though.

I can't see how IMRO can be bypassed by tho??

watty

If people use their own personal headphone FM Radio via Leak feeder, then IMRO doesn't apply.

Get REALLY cheap TV coax. The sort with a pathetic cobweb of copper. See how good it leaks with NO slots cut in it.

Every* 2m to 10m cut a slot in the outer "screen" about 0.5m long and press back the screen about 3mm, then insulate with glue gun. Only at "black spots". Connect to double screened low loss (i.e. sat cable) from area to cover to high gain outdoor aerial. Terminate far end with a 75 ohm resistor. Perhaps at most a 3dB or 6dB bandII amp only for feed loss to start of leaky feeder or else you can get feedback.


(*The fewer slots the less signal)

Perhaps slightly non-intuitive, each slot is equivalent to a dipole at right angles to the coax.

Fuzzy Clam

Ok, I'm with you regards the leaky feeder.

To that point, then my idea of using an i-trip type device (with earphones) is legal from both Comreg and IMROs side.

TBH, I'm not 100% sure of IMROs stance on using earphones in the workplace. I have been told that a PPL is not required but, IMRO being the money grabbing leeches that they are, would probably say otherwise.

watty

You don't need an iTrip. Just FM receivers.

Mike 1972

Do Itrip's (other low power FM Transmitters are available ) (or the USB chargers powering them) not generate a lot of RF noise ?

The reason I ask is because when I tried relaying the signal from my mobile phone radio at work all I got was white noise ?