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Old 07-16-2007, 10:01 PM
Grant Stockly Grant Stockly is offline
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Join Date: Jan 2005
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There is a 2 phase clock on the CPU card generated from two one shot timers. The parts listed in the manual for this part were starting points. The CPU card even has two sets of pads for each resistor and capacitor to allow for paralleling parts.

When I was debugging my first CPU card I looked at the clock on two other vintage cards. According to Intel's spec sheet those two vintage cards should not be working at all. If an older Altair is running badly then its possible that the 2 phase clock is responsible.

The closer the clock is to spec the less temperature or electricity fluctuations might impact the stability of the Altair. The ultimate fix is to use an Intel 8224 like this guy:

http://www.stockly.com/forums/showthread.php?t=325

Grant
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