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How to increase range of FM transmitter?

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lsister

New Member
I bought the Linex FM transmitter:

http://cgi.ebay.ie/Linex-Wireless-F...11694QQcmdZViewItemQQ_trksidZp1742.m153.l1262

The problem I have is that there are only a few frequencies to choose from and that there are radio channels broadcasting on basically all those frequencies. If you are not close to the device, the radio station will overrule.

How can I increase the range or signal strength of the device?

I read about:
- Increase voltage; can this be done; how much can the device handle?
- Antenna; currently it has a wire antenna. What antenna should I use (just connect to the wire?)
- ?????? any advice is welcome

thanks!
 

stevez

Active Member
You probably can't change the power output of this device significantly without significant modifications. It seems likely that significant modifications would yeild a device that is illegal in many countries.

You could add an amplifier to the output but as with "significant modifications" it's likely to be non-compliant.

Things that you might do is try to reduce the incoming signal strength of the competing radio stations - by removing/reducing the antenna to the receiver and placing the device closer to the reduced antenna. Clearly you'd need to install a switch for this to be practical but experiment first.

Adding more antenna to your device might work but it's hard to say. More wire changes the apparent load on the transmitter possibly negating any expected improvements.

To be effective, the improvements have to be profound. You won't notice a 20% improvement, it would have to be a 200% improvement or more.
 

Torben

Well-Known Member
Probably the only thing you can realistically do is make a pair of directional antennas (one for the transmitter and one for the receiver) and point them right at each other, hoping that they don't line up with the interfering stations. Of course that won't help if the transmitter and receiver aren't stationary. And how realistic it is kinda depends on what frequency/frequencies you want to operate on.


Torben
 

whiz115

Member
try this... i think it's much more cheaper and you can choose whatever frequency within the FM band.

http://www.sourcingmap.com/wireless-transmittermodulator-for-ipod-mp3-pda-p-11932.html

and you can extend your range with this

http://hem.passagen.se/communication/ipod.html

also check this out because from outside they look the same but inside it's not always the same circuit and you might have difficulties locating the RF out point.

http://homepage.ntlworld.com/tony.ling/radio/workbench/nanotransmitters/668a/668a_tech.htm


i hope i helped.
 

audioguru

Well-Known Member
Most Helpful Member
The expensive 2.5W RF amplifier has hardly any specs.

All amplifiers except this one spec the input level required.
Its low frequencies are cutoff at 100Hz so it does not have deep bass.
 
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