These are the attenuators I have build. It is a Pi circuit using 1206 series SMD resistors on a double sided 1.6 mm PCB with via holes. There is a male and a female SMA connector for I/O. The Resistors are for 20 dB 2*62 ohm & 1*240 ohm, for 10 dB 2*100 ohm & 1*75 ohm, for 6 dB 2*150 ohm & 1*39 ohm , for 3 dB 2*300 ohm & 1*18 ohm.

And performance now S11

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And smith charts S11

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