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as im in need of Low- and Highpass filters i would like to simulate my circuit using LT-Spice.

I hope that i can get optimal caps and coils values like that.

So i simply started to build my pi-network lowpass filter in LT-Spice and got the simulation results (please check the picture in the attachement)

On my board i have a SMA connector, that ouputs the RF-Signals of an antenna mux and that same SMA connector is also used for the circuit board's supply voltage of 9V.

So now i need a Lowpass filter for the DC supply and a Highpass filter for the RF-Singnals.

I would like to simulate this in Spice, however im not sure how to approach.

E.g. im not sure what frequencies should pass for the DC supply and where to start blocking? (Lowpass)

For the RF-Signals, i need 860-870MHz to pass. (Highpass)

What are the typical values to start with?

(please check attachement for my filter structure and first approach to simulation, i started with a lowpass filter for the DC supply)

In Spice i made an AC analysis :

AC Amplitude: 10V

points per octave= 100, start frequency= 1Hz, end frequency=200MEG

Also im think theres more about this simulation, i guess i also somehow should model the load etc.?

I would like to be able to estimate the values of my filters using simulation but im way too new in this field so i hope you can help me.

I appreciate every little hint, explanations and links to further information! :)

Thank you in advance! :)

Kind regards, Tom.

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# Simulation with Spice to get coil and caps values

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