 Welcome, myself, Mr. V. V. Angire, assistant professor, electronics and telecommunication engineering department, WIT, Sulapur. In last lecture, we have seen how Z parameter can be represented in terms of y parameters. So, in this video lecture, we are going to see how Z parameters can be represented in terms of ABCD parameter. So, this is interrelationship between parameters of two port network part two. Learning outcome, at the end of this session, students will be able to use two port network parameters to find unknown voltage, current, impedance or admittance. So, before starting with actual derivation, that how Z parameters can be represented in terms of ABCD parameter, you have to pause this video here and you have to answer a question that what are the dependent and independent variables of voltage and currents are used by writing the equations related to Z parameter and ABCD parameter. Now, we will start with actual derivation that how Z parameters are to be represented in terms of ABCD parameter. So, for that case, we have to write the equations related to Z parameters as well as ABCD parameter. Now, first we will write equations related to Z parameters. So, in case of Z parameters, dependent variables are V1 and V2 and independent variables are I1 and I2. So, equations are V1 is equal to Z11 I1 plus Z12 I2. This is first equation and next equation is V2 is equal to Z21 I1 plus Z22 I2. So, we will make this as an equation 1, this as an equation 2. Now, we will write equations related to ABCD parameter. In that case, V1 is equal to AV2 minus VI2. So, here V1 is dependent variable and voltage V2 as well as current I2. These two variables are independent variables. Second equation is I1 is equal to CV2 minus DI2. So, we will make this as an equation number 3 and this as an equation number 4. Now, I will simplify equation number 4. So, equation number 4 is I1 is equal to CV2 minus DI2. I can write this equation or I can simplify this equation as CV2 is equal to I1 plus DI2. And now, V2 can be represented as 1 by CI1 plus D by CI2. We will make this as equation number 5. Now, compare equation number 5 with equation number 2. So, if we compare equation number 2 and 5, so from this we can say that value of Z21 is 1 by C and value of Z22 is D by C. So, from this, we get value of Z parameter Z21 and Z22 as Z21 is equal to 1 by C and Z22 is D by C. Now, what we have to do is put value of V2 from equation 5 in equation number 1. So, we have to use the value of V2 from equation 5 and we have to use it in equation number 1. So, first we will write the equation number 1. So, equation 1 is V1 is equal to Z11 I1 plus Z12 I2. This is equation related to Z parameter. This is equation 1. So, here we have to put value of equation 5 in equation number 3. It is not 1, it is equation number 3, is it? So, we will write equation number 3. So, equation number 3 is V1 is equal to AV2 minus Bi2. Now, value of variable V2 from equation 5, we have to put it here. So, V1 is equal to A in bracket. It is 1 by C I1 plus B by C I2 minus Bi2. So, V1 is equal to A by C I1 plus A D by C I2 minus Bi2. Now, we will take terms common which are related to current I1. So, now equation will simplified as this. V1 is equal to A by C I2 plus A D minus BC upon C into I2, is it? Now, make this as equation number 6. Now, compare equation number 6 with equation number 1. So, from this we can say that value of Z11, this is I1. Value of Z11 is A by C and value of Z12 is A D minus BC upon C. So, after simplifying equation number 3 and putting the value of V2 from equation number 5, we will get Z parameter in terms of ABCD parameters and the values are Z11 is equal to A by C and value of Z12 is A D minus BC upon C. Now, so this is interrelationship between parameters of two port network. So, like this we can write Z parameter in terms of H parameters or G parameters and likewise we can write one two port network parameter in terms of other parameters. So, any two port network parameter can be represented in terms of other two port network parameter. So, while preparing this video lecture as a reference I have used circuit theory analysis and synthesis by A Chakrabarty. Thank you.