hey what's going on guys, this is Kedar
here
so today we are going to build an FM
transmitter that is ultra small, so
let's get started, now if you do a quick
little Google search on to FM
transmitter circuit. you'll get many
simple yet working circuits. if you
prototype this circuits. it works really
good but still they are big enough so
they are not considered as spy !
so after searching little bit onto the
internet i found this very interesting FM
transmitter modules, this modules have a
built-in microphone and you can also
adjust the frequency by this potentio
meter so i decided to use this modules
for the battery i'm going to use
this 3.7 volts lipo battery. i'm using
this hundred milli amps per hour capacity
and it will last more than 50 minutes of
use. so start by soldering positive and
negative terminal of the battery to FM
transmitter module and there it is guys
your FM transmitter should be
transmitting now by default the FM
transmitter range is not good. so we need
to build an antenna so for that I'm
going to use this conductive copper foil
and i'm going to install this copper
foil in cross manner like this and I'm
going to solder this wire to the middle
terminal of FM transmitter board so
there it is guys our mini FM
transmitter bug is ready.. now to set up we
need to turn on any kind of FM receiver
i'm going to use my smartphone FM, one of
the advantages of using that I can also
record my audios through this one so
turn on your fm receiver and start by
scanning your FM next channels and
eventually you will find your own voice
coming out through the FM receiver and
now if you want to set your FM
transmitter on to the particular
frequency, you can do that by setting
your frequency onto your FM receiver
then
tune the potentio meter on to the FM
transmitter module so i'm going to show
you how it will sound like. now in this
test I'm going to use my smartphones
built-in recording feature so let's hear
to that audio. i just finished making
this spy FM transmitter bug, so this
small device can transmit your audio
into FM frequencies. so right now i'm
recording this voice into my smartphone
fm recording feature, so let's hear the
ambience
you can clearly see how sensitive the
mic is because (if i whisper into the mic you can here my voice pretty clearly) whispering
that's how sensitive the mic
is
so this is my FM transmitter bug you
can take a look at its
size. it's really small
we can fit in almost any kind of spaces
now if you want to make this bug much
smaller than this you can actually use
this button cell batteries, you can use
two of those in series you can make this
bug
more thinner, anyways guys now I'm really
interested to know where you're gonna
use this one. so let me know in the
comments down below guys and you're like
really helps me a lot so please hit that
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projects and thanks for watching goodbye