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Re: I have a IIgs. So now what?
Michael J. Mahon wrote:
> David Wilson wrote:
>> On Mar 2, 9:14 pm, "Jon" <jon...@gmail.com> wrote:
>>
>>>Hmm, even more interesting is, Jaycar also has 7406s (CAT. NO.
>>>ZS5806). Is the clone Disk ][ controller a 1:1 clone of the apple
>>>card? It might be better then to use the 74LS05?
>>
>>
>> 74xx = TTL = (10mW/10ns)
>> 74Lxx = Low Power TTL = (1mW/30ns)
>> 74Sxx = Schottky Diode TTL = (20mW/3ns)
>> 74LSxx = Low Power Schottky Diode TTL = (2mW/10ns)
>> 74ALSxx = Advanced Low Power Schottky Diode TTL = (1mW/4ns)
>>
>> So replacing a 74LS chip with the 74 will have about the same timing
>> but will consume more power.
>>
>> If you can determine that the outputs of the 74LS06 will never exceed
>> 5v, a 74LS05 will be a good replacement.
>
> It's actually the other way around--the '06 was a harder-to-find
> replacement for the correct '05.
Interesting. I can say with a fair degree of certainty that it is the
original chip though. There are no signs of chip removal.
Something did just occur to me. I may check the input of the IC that
corresponds with the dead output. It seems highly unlikely that the damage
would have skipped one IC and happened on the next, but it is worth
checking.
Tristan.
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