Well ,there is a great difference between these two words
but may feel same practically! Once my friend Manu thomas
was completing his excel project ,perhaps violated some ckt
connections .Anyway a "man" call for me had been made .At
that time we were completing our project on robotics .
Stunned looking at the result!
The project included a laser based voice transmitter and receiver .
When he had removed the laser somewhat due to some power
supply problems related to the laser ,becoz he used the laser torch
which is available in market for just 30.00RS at marine drive ,
and instead of battery ,he used the 3v from the transmitter ,
connected only for the demonstration .Anyway demonstration
completed successfully.The transmission quality was great with
the help of laser .When the wire connecting the laser to the
transmitter broken it was found that there was a slight change
in quality of the sound transmitted,instead of vanishing of received
signal.(he used mobile phone music as sound source).
Astonished!proving nothing in theories!sound had been transmitted
without modulation without antenna which requires large height!
Is it possible?
With the help of a simple fixed bias ckt and simple loop antenna of
1/2 meter we have transmitted (exception)the sound signal
(audio frequency ) for 1 meter without the help of large antenna and modulation .
Initialy the target was a laser based transmission system ,
although the mission was achieved ,a fact came to know that there is
is a "coupling" existing between the transmitter and the receiver
when the distance is very less .
Here is the transmitter and the receiver.It was given
in the efy official web site.Here in the transmitter ,when
the laser torch was removed ,it was seen that the signal
at the microphone ,is transmitted (assumption)to abt 1
meter .All guys astonished feeling the result "without a
modulation scheme,without an antenna,without a carrier
,it is not possible to transmit the base band signal at all".
The fact was a truth we were not able to distinguish
between the coupling and the transmission until,
prof:T.K.Mani explained the phenomenon with proof.
That day i have realised that we are in the world of a mixed
signals all around us but not identifying them .For the purpose
we may require a frequency translator (mixer)to make them
feel with our natural sensors.
The transmitter was simplified by us to only a fixed bias ckt.
Thus realised that the problem is not with the transmitter .
"receivers are difficult to design than transmitters" that was
a natural truth.In the receiver the amplifier stage we
have used here is a one with high gain hence any noise or
anything which is coupled through anything(need not be a peice
of wire human body itself is a coupler)will be amplified and a
resulting sound is produced .
but may feel same practically! Once my friend Manu thomas
was completing his excel project ,perhaps violated some ckt
connections .Anyway a "man" call for me had been made .At
that time we were completing our project on robotics .
Stunned looking at the result!
The project included a laser based voice transmitter and receiver .
When he had removed the laser somewhat due to some power
supply problems related to the laser ,becoz he used the laser torch
which is available in market for just 30.00RS at marine drive ,
and instead of battery ,he used the 3v from the transmitter ,
connected only for the demonstration .Anyway demonstration
completed successfully.The transmission quality was great with
the help of laser .When the wire connecting the laser to the
transmitter broken it was found that there was a slight change
in quality of the sound transmitted,instead of vanishing of received
signal.(he used mobile phone music as sound source).
Astonished!proving nothing in theories!sound had been transmitted
without modulation without antenna which requires large height!
Is it possible?
With the help of a simple fixed bias ckt and simple loop antenna of
1/2 meter we have transmitted (exception)the sound signal
(audio frequency ) for 1 meter without the help of large antenna and modulation .
Initialy the target was a laser based transmission system ,
although the mission was achieved ,a fact came to know that there is
is a "coupling" existing between the transmitter and the receiver
when the distance is very less .
Here is the transmitter and the receiver.It was given
in the efy official web site.Here in the transmitter ,when
the laser torch was removed ,it was seen that the signal
at the microphone ,is transmitted (assumption)to abt 1
meter .All guys astonished feeling the result "without a
modulation scheme,without an antenna,without a carrier
,it is not possible to transmit the base band signal at all".
The fact was a truth we were not able to distinguish
between the coupling and the transmission until,
prof:T.K.Mani explained the phenomenon with proof.
That day i have realised that we are in the world of a mixed
signals all around us but not identifying them .For the purpose
we may require a frequency translator (mixer)to make them
feel with our natural sensors.
The transmitter was simplified by us to only a fixed bias ckt.
Thus realised that the problem is not with the transmitter .
"receivers are difficult to design than transmitters" that was
a natural truth.In the receiver the amplifier stage we
have used here is a one with high gain hence any noise or
anything which is coupled through anything(need not be a peice
of wire human body itself is a coupler)will be amplified and a
resulting sound is produced .
Comments
-Mani