The sketch below identifies the Wye Network & Delta Network (T or Pi) elements.

Wye/Delta Transformations                  Convert a Wye-network to a Delta and vice versa.                  Note: Elements are either resistive OR reactive.                  Wye/Delta or Delta/Wye (1 or 2) [<Enter>=Quit] ? _

Let's convert a T-Pad to a Pi-Pad. A 3 dB 50 ohm T-Pad has Z1=Z2=8.550 ohms, and Z3=141.926 ohms. First, in answer to the question up above, choose "1" and then input "8.550,8.550,141.926" and press <Enter>.

Here is the output calculation for the T to Pi conversion:

                ZA = ZB = 292.402 ohms   (270 ohms 5%)
                ZC = 17.615 ohms              (18 ohms 5%)