This schematic is presented as a courtesy of The Whiterook Products Company. You can "homebrew" your own Code Buddy or buy their KIT or FULLY ASSEMBLED Code Buddy Code Practice Oscillator. We sincerely hope you enjoy learning and practicing the Morse Code! 

                     Code Buddy Code Practice Oscillator
                               Parts List

                      U1 - NEC 555 Timer IC Chip

        C1 - 0.22 uF 25 V Tant.          R1 - 680 ohm
        C2 - 10 uF 16 V                  R2 - 1K  ohm
                                         R3 - 25K ohm Tone Control
        B1 - 9 Volt Battery              R4 - 500 ohm Volume Control
                                         R5 - 10  ohm
        J1 - Key Jack

        SP - 8 ohm Speaker or Headphones
                       Output

The Code Buddy was featured as a construction article in the July 1996 issue of Nuts & Volts Magazine.

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