Draw the diagram for PAM generation using transistors. Explain its working.

1 Answer

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Explanation:-1. Transistor Q1 is used in the active region so it has been provided with DC biasing to its base. 2. Modulating signal is applied to the base of transistor Q1 3. In the emitter of Q1, the other switch transistor Q2 is used with load resistor in its emitter. 4. Sampling clock as a carrier signal is given to drive its base and transistor Q2 is driven into saturation. 5. PAM output is taken from emitter of this switching transistor Q2. 6. When sampling pulse given to the transistor Q2 it becomes ON and we get pulse with amplitude same as modulating signal at that time. 7. In the time interval between sampling pulses output is zero. Thus we get the output as PAM.

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