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Schematic of Step Attenuator

Searched online to find some schematics of step attenuators and then edited schematic into QUCS.

Simulator result

DB

Volts Expected DB Calc DB
5    
4.46 1 -0.99
3.55 3 -2.97
2.52 6 -5.95
1.26 12 -11.97
0.403 22 -21.87
0.0675 42 -37.39

The +20 db step is off quite a bit.

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