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4 Watt FM Transmitter


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Hi Cerium,
That 4W FM transmitter doesn't have pre-emphasis (treble boost) like radio stations have, so its received audio won't have much treble. Its received audio will sound something like an AM radio or like your stereo with its treble control all the way down. :(

You can mix the stereo output of your CD player into mono and reduce its output level with a 47k resistor from each of its two channels to C2 without using the TR4 stage.

You can add pre-emphasis by connecting a 2.2nF capacitor in parallel with each 47k resistor for Europe and Australia. Use 3.3nF for North America. ;D

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Hi Cerium,
You must get rid of TR4 and R2 and the rest of the mic preamp so it doesn't load down your external input.
Don't you want the stereo input to be combined into mono like this?:

Got a mod for the 15W version to do stereo input?
http://electronics-lab.com/projects/rf/014/index.html <-- this 1.
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