How to make a fm transmitter without amplifier?

I want to build a fm transmitter with 400m range. I already have a custom made amplifier all I need to know is how to transmitt the signals. 
I don't need a mic I will play it through mp3 player. plaese help me and give me a circuit.

sorry for my bad english.

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samaddon4 years ago
i also recommend mpilchfamily's answer! just search for FM TRANSMITTER~! HERE is a simple circuit diagram you need to connect the output of your amplifier with the input of this circuit!
Hope it helps
full schem FM transmitter.jpg
iceng samaddon4 years ago
Ground addition to your collection :-)

They are NOT equivalent though. You can distinguish "chassis ground" "electrical ground" and "electrical reference"
But in common circuits there is generally the ground is negative side of the battery and the electrical ground is generally used in ac power management!
That's not what I am arguing. The symbols mean different things, not ground. And electrical ground is used in many areas than AC power.
Have you conducted a simple internet search for FM transmitter schematics? It will give you a wide range of options but they can all be tricky to get working and dialed into the correct FM frequency you want.