[SOLVED] Equations for T Pad with Different Source and Load Impedances

[Fred_B]

Hi,

I need the equations for a T pad with different source and load impedances. I noticed that with the same source and load impedances, the equations for the Pi pad and T pad are mostly just reciprocals of each other. I tried to follow the same pattern the the Pi pad equations for different source and load impedances to convert those into the T versions although I failed to quite get it. Any help would be appreciated. Below is a link to page I used for the Pi and T pad equations.

Pi Attenuator Calculator

Our pi attenuator calculator is perfect if you want to build an attenuator and don't know how many ohms to use in your resistors.

www.omnicalculator.com

https://www.electronics-tutorials.ws/attenuators/t-pad-attenuator.html

Regards,
Fred B.

 

[FvM]

Please tell the impedance and attenuation values that failed in your calculation. You understand that unequal impedances involve a minimal attenuation that can't be deceeded?

 

[Fred_B]

dB = 6, Z1 = 50, Z2 = 53.5

Attached is my attempt to convert the asymmetrical pi pad equations into a set of asymmetrical t pad equations following the pattern in the symmetrical set of equations, which is basically that everything following the impedance term is turned into a reciprocal to convert from PI to t.

I plugged my resulting set of equations into a spreadsheet and the answers that it gave were off as far as the attenuation and the impedance match goes.

 

[FvM]

I didn't try to reproduce your PI->T transformation, the result is however different from tutorial which gives correct results.
I conclude you did something wrong.

 

[Fred_B]

I didn't try to reproduce your PI->T transformation, the result is however different from tutorial which gives correct results.
I conclude you did something wrong.

View attachment 186728

I appreciate your reply.

Best regards,

Fred B