EFFECT OF SOURCE IMPEDANCE and THE COMBINED EFFECT OF RS AND RL

EFFECT OF THE SOURCE IMPEDANCE (RS)
Our attention will now turn to the input side of the two-port system and the effect of
an internal source resistance on the gain of an amplifier. In Fig. 10.10, a source with
an internal resistance has been applied to the basic two-port system. The definitions
of Zi and AvNL are such that:
The parameters Zi and AvNL of a two-port system are unaffected by the internal
resistance of the applied source.











































COMBINED EFFECT OF Rs AND RL
The effects of Rs and RL have now been demonstrated on an individual basis. The
next natural question is how the presence of both factors in the same network will affect
the total gain. In Fig. 10.14, a source with an internal resistance Rs and a load
RL have been applied to a two-port system for which the parameters Zi, AvNL
, and Zo
have been specified. For the moment, let us assume that Zi and Zo are unaffected by
RL and Rs, respectively.