FM Transmitter

[juan123]

Is there a simple but yet powerful FM transmitter that I can build? I'd like it to have a 2-4 mile range and to allow me to change the frequency from 88-108mhz. Thanks for any help.

 

[Klaus]

Have you checked if what you are trying to do is LEGAL in your country?

88 - 108 Mhz is the FM radio band in a lot of places and the authorities would not look kindly on somebody causing interference there.

 

[dde2004]

Hi,

I can't help you with the 88 - 108Mhz frequency range.
But if you would like to go to a much higher frequency 5.8 - 5.9GHz, you could get a much further transmittal distance as well, have a look at.
ADF7025 - Analog Devices
ADF7012 - Analog Devices
ADF4016 - Analog Devices

All used in conjunction with each other. you can transfer baisically any type of data or voice.

You could also have a look at
TRF6900 - Texas Instruments.
still not within the frequency range but worth a look.

you might want to include an FM modulator with the TI chip to lower to those required frequencies.
But i can assure you it will be near impossible to get a 2 - 4 mile range in that frequency range. you would need at least a 50W transmitter, depending on your area as well, there are many factors contributing to the power required.

Regards
David

 

[dde2004]

correction

sorry :?

50W infact would not be required to transmitt that distance.
If you used the Analog devices IC's in conjuction, 1Watt of transmittal power would get you about 10-15kms (6-9miles). the analog devices IC's provide that amount of power. if you wanted to amplify if further you also could if you like.

Thanks
David

 

[juan123]

Wellll....

Maybe I exagerated in the range, I'd like a 1-2mile range, 2-4 was a little off. Therefore, can anyone give me a schematic of a transmitter that I could build, I'd like to use it as a neighborhood radio station. Thanks! :lol:

 

[gerty]

Try **broken link removed** . They have several kits to choose from 8)