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Classic II bomarc audio schematics

marcelv

Well-known member
Can someone confirm the bomarc schematic for the classic II is wrong regarding pin 1 and 2 of the DFAC?

classicIIaudio_wrong.JPGwrong version (pin 1 connected to pin 2 and swapped)



classicIIaudio.jpgcorrected version


Second question
where does the via next to C11 go

ciiboard.JPG
 

marcelv

Well-known member
checklist I used for the audio repair on the classic II rev A board

C3 47uF 16V
- gnd
+ R2, R7, R15

C4 47uF 16V
- phones switch
+ pin 5 U1

C5 10uF 16V
- gnd
+ pin 8 U2 (78L08), R21

C6 10uF 16V
- gnd
+ R6 (4k7 to R15)

C7 10uF 16V
- gnd
+ pin 7 U11 , R33

C8 10uF 16V
- gnd
+ pin 3 U1

C9 1uF 50V
- pin 10 DFAC
+ R29

C10 10uF 16V
- mic in
+ pin 3 U11 , R7

C11 10uF 16V
- gnd
+ pin 2 DFAC


pin 1 DFAC is connected to R32 , R37


C12 10uF 16V
- R35 , U11 pin 6
+ pin 6 DFAC , R40

C13 47uF 16V
- gnd
+ pin 1 U12

C14 10uF 16V
- gnd
+ pin 1 U2 (78L08)

C15 1uF 50V
- pin 12 DFAC
+ pin 13 DFAC , R37
 
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