How to attenuate certain FM frequencies?

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g33ky
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How to attenuate certain FM frequencies?

Post by g33ky » Sat Aug 08, 2020 4:07 pm

Hi you lot. Does anyone know if there is a way to block certain FM frequencies while letting others through? Where I am I have Storeton, Llangollen and Capital Liverpool blasting into my SDR meaning I can't set the gain too high without having receiver overload. I know there are full FM band blockers but thats not what I'm after :tup.
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radium98
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Re: How to attenuate certain FM frequencies?

Post by radium98 » Sat Aug 08, 2020 9:01 pm

put the rx in a farady cage ,what an option ,or use a band pass filter tunable.

Albert H
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Re: How to attenuate certain FM frequencies?

Post by Albert H » Sun Aug 09, 2020 4:25 am

Neither is going to work, Radium - he just wants to eliminate particular specific frequencies.

You need stub filters cut for the frequencies that you need to attenuate. The ARRL handbook shows how to calculate and tweak them.
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radium98
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Re: How to attenuate certain FM frequencies?

Post by radium98 » Tue Aug 11, 2020 6:58 am

thanks albert

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