C - TX IF

Updated Schematic

[UHD Schematic]

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Heathkit Changes (August 21, 1978) from SB-104-70

Resistor R-332 is selected to set the power output to 100 watts, +/- 1 dB. R-332 may be any one of the following four 1% resistor values: Always replace R-332 with a resistor of the same value.

Updates (SBM-104-2)

Does not apply to 85-1929-x board version

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Page 13 involving cutting a ground trace between Q302 and Q303 rescinded by Service Bulletin SB-104-76.

SB-104 => 85-1420-x

PC Board

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This board has been updated re. SBM-104-2

X-Ray

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Schematic

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HW-104 => 85-1627-x


PC Board

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This board has NOT been updated re. SBM-104-2. Notice power adjustment.

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This board has been updated re. SBM-104-2

X-Ray

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Schematic

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My HW-104 has this board instead. See below for schematic.

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S-104A => 85-1929-3


PC Board

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X-Ray

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Schematic

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