B - TX Audio and Voltage Regulator

Updated Schematic

[UHD Schematic]

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Heathkit Changes (May 19, 1976) from SB-104-40

  1. Reduce mic gain
    1. R207 from 4.7M to 1.5M
    2. R209 from 120K to 33K

Updates (SBM-104-2)

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HW-104 => 85-1634-2

PC Board

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X-Ray

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Schematic

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Regulator components removed 11/2023

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SB-104A => 85-1580-5

PC Board

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X-Ray

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Schematic

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