Re: Inverse and Flash don't work :(

[mjmahon@aol.com (Michael J. Mahon)]

Marco replied:

>Michael J. Mahon wrote:
>
>> This sounds like a pre-Revision 7 main board.
>> 
>> There are two ICs common to both inverse and flashing character
>> generation,
>> the 74LS02 OR-gate at B13 and the 74S86 XOR-gate at B2.  If I had to
>> choose, I'd try replacing the 74S86 first.
>
>I've changed  both 74LS02 and 74S06 but inverse and flashing charater don't
>work too.
>
>> If it were only flashing that didn't work, then the 74LS08 (B11) or the
>> 555(B3) would be the likely suspects.
>
>I noticed that there are another 74LS08 in motherboard, so I tryed to 
>switch them... but again there are the same problem and both inverse and
>flashing character dont work. I will try to change so 555...
>
>Thank you!:) I hope to repair my first lovely computer.
>Do you kown where I can find main board's schematics ?

The schematic of the pre-Release 7 board is in the Apple II Reference
Manual (the little half-size one).  I think it is on the web, too, but do
not have the URL.

-michael

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