FT-991/A Preselector RX Filter characteristics

Discussion in 'Radio Circuits, Repair & Performance' started by PY2RAF, Jun 5, 2019.

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  1. PY2RAF

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    Hi there List,

    With too much free time in my hands, I was really curious to find out what is the actual pre-selection RX bandwidth for each main band: HF, VHF and UHF.

    After identifying the filters, I put the circuits in LTSpice and ran the simulation. The results are in the below pictures.

    I got intrigued on why the UHF band was extended that long.

    For completeness, the dotted line depicts the signal phase.

    73s de PY2RAF! o/

    Attached Files:

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