Make a 1.5v Single-Transistor FM Transmitter





I'm gonna show you How to make a Simple FM Transmitter that works with only an AA battery.

47 pF Ceramic Capacitor x1
33 pF Ceramic Capacitor x1
10 pF Ceramic Capacitor x1
22 uF Electrolytic Capacitor x1
2SC655 (or BC548) Transistor x1
Single Battery Holder (AA Size)
small Breadboard/PCB
10cm Magnet wire x2
Audio Signal Source (e.g. a MP3 Player)

Soldering Iron

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Step 1: The Circuit and Parts

Here is the Circuit we're going to make.

Step 2: Start Soldering Parts on PCB

It takes about 10-12 mins to do this.

Step 3: Make the Coils

Wrap the first Magnet Wire around a thick pen or a size AAA battery.

Do the same for the second Magnet Wire, too.

...Then Solder them on PCB

Step 4: Final Steps

Solder the battery holder wires, Antenna Wire, and the Audio Source.

Step 5: Turn on Your Radio

Turn on a radio and set it at 89MHz FM
Connect the "Audio In" of the Transmitter to your MP3 Player (or any other non-amplified things playing music).
Place the Battery in the holder.


2 People Made This Project!


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20 Discussions


3 years ago

And how many turns are needed?


3 years ago

hi cable Guy!!.

What wire gauge are you using?, I went to the electronics shop and I found that I several gauges :D

I bought on that its not thinner but not so fat.

It is NOT the capacitors (however, the Farads matter) the frequency is changed based upon the oscillation of the inductors (the coils of wire) if you want to change the frequency, search the internet for a calculator that to find how many turns of wire you'll need for a specific frequency.


6 years ago on Introduction

There is a problem in this circuit, every time frequency is change when you move the circuit. Can i put variable/trimmer capacitor in this circuit. If yes where to put the variable capacitor and which type of capacitor. Thanks