Design a 15 dB π Attenuator with 600Ω Impedance

[shaltera]

Homework Statement

Design a π section symmetrical attenuator to provide a voltage attenuation of 15 dB and a characteristic impedance of 600 Ω.

Z_c=600Ω,$\alpha$=15dB (attenuation)
Z₁,Z₃=?

Homework Equations

The Attempt at a Solution

$\alpha$[dB]=20log(V_in/V_out)=15
$\alpha$=5.623

V_in/V_out=(Z₁+Z₂)/Z₁

Z_c=√Z_ocZ_sc
Z_oc=(Z₁(Z₁+Z₃))/(2Z₁+Z₃)
Z_sc=(Z₁Z₃)/(Z₁+Z₃)

Z_c=Z₁√1-2/(2+Z₃/Z₁)

Z₁D=600

Z₃/Z₁=4.623
D=0.835

Z₁=718Ω
Z₃=3320Ω

 

[NascentOxygen]

I'd be inclined to show the arrows for Vin and Vout upside down to how you have, though I guess it makes no difference.

Vin/Vout=(Z1+Z2)/Z1 should be Z3 not Z2

Your figures give -15 dB, and 609.6 ohms for Zin

 

[shaltera]

I have made a typing error,it is Z3