About FM transmitter DIY Learning Kit for Beginners
Assembly tutorial is available at
www.buildcircuit.com
. If you have been making DIY
kits, you will easily figure out where the components are to be soldered, it is very
easy.
This is one of the easiest and simplest FM transmitters for amateur and electronics
beginners. With this DIY kit, you can transmit your voice or audio over an ordinary FM
radio within the
FM broadcast band
. The best thing about this transmitter is that you don’t
have to make your own inductor for this kit. Making an inductor is bit hard for amateurs.
Besides, this kit is not only capable of transmitting voice using microphone but also
transmitting music from your music player.
You can use this FM transmitter/microphone in two ways:
a.
Audio transmission using electret microphone: You can transmit your voice to
an FM radio with the electret microphone. You can also place the transmitter circuit
close to any loud speaker so that the microphone picks up the sound and transmits
to the tuned FM radio.
b.
Audio transmission connecting speaker stereo jack to audio source: For
hearing better sound, you may connect it to your computer, ipod or mp3 player
using a speaker jack. The audio of your music players get transmitted to your nearby
radio.
Features:
Frequency Range: 88-108MHZ (Frequency can be changed by moving the inductor coil).
Operating voltage: 3V-9V
Transmission range: More than 30 meters in open area. The transmission depends upon
the length of antenna used. Kit package includes a simple 10cm long wire. The signal can be
transmitted even further with longer antenna of length around 50cm.
How does it work ?
Electret microphone (MIC) converts the natural sound signal into the electrical signal. The
capacitor C2 is coupled to the base of transistor Q1- S9018 and whenever there is signal
from the microphone, the junction capacitance of the transistor changes that contributes to
change in oscillation frequency.
