Stereo transmission requires two different signals - a left (L) and right (R) signal - to be modulated, transmitted, received, and demodulated without distortion. This is achieved by using an L+R sum signal that is compatible with mono receivers, and an L-R difference signal to provide stereo separation. At the receiver, a low pass filter extracts the L+R sum signal, while bandpass filters extract the L-R difference and pilot signals which are then used by a synchronous detector and de-emphasizers to recover the original L and R signals. Preemphasizers and de-emphasizers are used to improve the signal-to-noise ratio by modifying the frequency content of

2. What Stereo Means :-

3. How then comes the
virtualization ??

4. What do we need for the
transmission?
• We need two different signals L(left) &
R(right) to be modulated, transmitted, received
and demodulated duly without getting distorted

6. We need :----
a.An input signal
b.Two preemphasizers
c.A DSB-SC modulator
d.A frequency doubler
e.A pilot signal
f. A summer
g.An FM modulator

9. Why do we need L + R & L – R??
A mono phonic receiver will work with only the
L+R component and there will no loss of
AUDIO(so the signal will have the backward
compatibility)

11. We need :----
a. An input signal (through a
LIMITER DISCRIMINATOR)
b. A Low Pass Filter(0-15 KHz)
c. A Bandpass Filter(19 KHz)
d. A Bandpass Filter( 23 – 53 KHz)
e. A pilot signal
f. A Frequency Doubler
g. A Synchronous Detector
h. Two Deephasizers

15. Preemphasizer refers to a system
process designed to increase, within a band of
frequencies, the magnitude of some (usually
higher) frequencies with respect to the
magnitude of other (usually lower) frequencies
in order to improve the overall signal-to-noise
ratio by minimizing the adverse effects of such
phenomena as attenuation distortion or
saturation of recording media in subsequent
parts of the system.

20. Deemphasizer refers to a system process
designed to decrease, within a band of
frequencies, the magnitude of some (usually
higher) frequencies with respect to the
magnitude of other (usually lower)
frequencies in order to improve the overall
signal-to-noise ratio by minimizing the
adverse effects of such phenomena as
attenuation distortion or saturation of
recording media in subsequent parts of the
system.

27. QUESTIONS ARE WELCOME