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       #Post#: 122--------------------------------------------------
       [solved] PI- vs. T-Attenuator Puzzle
   DIR By: Robert
       Date: July 3, 2025, 3:32 pm
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       MC12 gives different results for a 10 dB attenuator in Pi- and
       T-configuration respectively.
       The component values have been determined with one of the many
       online attenuator calculators.
       What is wrong here?
       Robert
       #Post#: 123--------------------------------------------------
       Re: PI- vs. T-Attenuator Puzzle
   DIR By: MC12
       Date: July 4, 2025, 3:17 am
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       Your resistor values are not correct for your pi and tee
       networks to be equivalent.  For one thing, it ought to be
       obvious that R8 should be smaller than R7 and R9, if the network
       on the right were equivalent to the network on the left.
       I assume you are aiming at 10dB attenuation with 50&#937;
       impedance, for which the tee network is correct.  If so, when I
       run the tee-to-pi calculations for myself (from first
       principles), I see what you've done is simply transpose your
       resistor values.  R5 should be 71.17&#937;, and R3,R4 should be
       96.26&#937;.
       Not so much a puzzle as a slip-up.  I'll leave it to you to work
       out whether that's your fault, or an error in the web calculator
       you used.
       #Post#: 128--------------------------------------------------
       Re: PI- vs. T-Attenuator Puzzle
   DIR By: MC12
       Date: December 22, 2025, 3:36 am
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       Is this solved now?
       #Post#: 129--------------------------------------------------
       Re: PI- vs. T-Attenuator Puzzle
   DIR By: Robert
       Date: December 22, 2025, 10:23 am
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       Problem solved.
       #Post#: 130--------------------------------------------------
       Re: [solved] PI- vs. T-Attenuator Puzzle
   DIR By: MC12
       Date: December 22, 2025, 6:36 pm
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       I've updated the thread title.
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