Do It Yourself

Accessories

External Speaker with Passive Filter

            I always use the Yaesu SP-767 speaker box with the internal passive filter for the 50MHz DX. Although I bought the Timewave 599ZX DSP filter later, the DSP is really silence, but if it compare with the SP-767, I felt that the passive filter is pure, clear, no machine noise and readable. It is impossible to bring the big speaker box for the outdoor field day at the hill top. So I want to make a portable speaker with the passive filter inside. If you are also want to build one for yourself, please see the following information. But make sure that the high Q, small internal resistance coil should be used for minimize the insertion loss of the audio signal.

Outlook	Inside the case

PCB Top	PCB Bottom

    Schematic Diagram in PDF format

    PCB Layout in PDF format

    Assembly Drawing

Specifications and Details :