i have short circuit stubs with different Zo (non of them is 50) and different electrical lenght
and i need to conert them to open circuit stubs
how can i do that?
adding 90 degrees to them doesnt seem to be right
Here's a Wiki page for you: http://en.wikipedia.org/wiki/Stub_(circuit)
The formulas are right there.
It would help a great deal to have a network analyzer available, or a TDR or FDR.