36 dB/octave low pass @6kHz?

[shabtek]

I was trying to figure out what these McMartin LCLCLCLC cards I found are for. they seem to be a low pass, they are 600Ω input.
My guess is AM broadcast band limiting or something related.
Does anybody have ideas for alternate uses? there are 5 20ish uH ferrite coils and several 7 to 33nF caps.

 

[Bo Deadly]

That must create a pretty serious phase shift. Enough to be basically a delay line in some respects. That might be interesting for something.

 

[john12ax7]

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