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Re: Dead II+ Rev.7 motherboard



"Michael Black" <et472@FreeNet.Carleton.CA> wrote in message 
news:ebncpm$b9s$1@theodyn.ncf.ca...
> Linards Ticmanis (ticmanis@gmx.de) writes:
>> Linards Ticmanis wrote:
>>
>>> Replacing the LS11 didn't help.
>>
>> I should add that I only had a 74HCT11 available as a replacement, which
>> maybe is not close enough in timing to a real 74LS11 to accurately
>> create the LD194 signal.
>>
> That HCT is CMOS, and the issue may be incompatibility with the lower
> power schottkey devices already in the II.  Before you panic too much,
> get the proper 74LS11.
>
>  Michael
>
Hello,

    When you look at several chips at Apple II+'s motherboard.  It is not 
wise to combine HCT chip and LS chip.  It requires to use the same power 
where it is flowing on the logic circuit.  All S and LS chips are used.

Bryan Parkoff