Updated acknowledgement details
removed the current gain equation from design part

The design is based on stability factor. Hence dependance on transistor current gain is irrelevant.
Slight improvemnt in theory section, figure formatted.
Added equation in results section
Typo corrections done. Added a step for plotting simple AGC characteristics
Misc. editing and formatting of contents ofchapter on  PAM generation and demodulation
signal waveforms of PAM changed

Two separate figures corresponding to modulation using BJT and switching IC are added  deleting the common figure.
Corresponding changes are made in the tex file too.
Correction done in circuit diagram of PAM using transistor

Added a missing resistor at the base of the transistor.
Modified the demodulator diagram as per the design.
Circuit diagram for PAM generation using IC modified

The connections for Vcc and GND are added to the IC 4016. The default
4016 IC component in geda has no provisions for them. Just addded a line
and indicated the pin numbers using text entry options in geda. A better solution may be required.
Miscellaneous edits in DSBSC using 633 IC

Content clarity enhanced. Filter design updated. COrresponding changes introduced
 in circuit diagram.
Misc. edits in AM circuit using 633

Content updated, filter design changed. circuit diagram modified
misc. formatting in fm using 555
removed some files created as place holders for fm generation and demodulation

There are other chapters discussing fm modulation using 55 and fm generation and demodulation using PLL IC.
Added waveforms for FM

frequency modulation with square wave carrier and sinusoidal message.
waveform generated in octave is added.
Added input and output waveforms for frequency modulation and demodulation