ye i can do the Z matrix, thx
the H one is true?

 

ok my proffesor told me its not true, can someone tell me whats the problem with my equations plz?
first picture its the circule, 2nd its my answer.
thank you

 

Have you confirmed that you have your original circuit correct?

You have port1 directly connected to port2 in your diagram.

 

If the two-port consisted of only a wire between port 1 and port 2, the h parameters would be:

[ 0 1 ]
[-1 0 ]

by inspection.

Some of the OP's circuit h parameters can be determined by inspection also.

Take this hint, csw123, and look carefully at your solution.

 

Your Z matrix is your post#13 is a little short on algebra.

Since this is a passive network and easier than one with sources I have worked through some algebra and left you some to finish off.

You must use your knowledge of basic circuits (ohms law, series, parallel resistors, voltage dividers etc) to deduce the expressions for the z parameters in the matrix.
At least they are all impedances (resistances in this case)

Your calculation of V2/V1 in this image:

is incorrect.

You have V = (R2+R4)/R2 * V1, but if a source V1 is applied, then that expression doesn't give V because the loading effect of R1+R3 is neglected. Likewise the other expression, V = (R1+R3)/R3 * V2

The ratio V2/V1 can be determined by inspection. Look at the original circuit involving R1, R2, R3 and R4, and consider applying a source voltage V1 at port 1. The resistor R2 drops out because it's connected in parallel with a voltage source.

Then R1, R3 and R4 form a voltage divider across V1, and V2 = V1*R3/(R1+R3+R4)

 

Ok ill try thx alot to all of you!