Apple ][e repair HAL PAL GAL 16v8 341-0170-A

Getting warm, in more ways than one

So in my last entry I mentioned that the ICs LS245, 341-0170-A, 74166, 6502 and 341-0150 were getting warm.  This wasnt the full list, the MMU, IOU and ROMs were also feeling a bit above room temperature, but it was subtle.  After looking at the schematic however, I think I now have a pretty good idea of what's going on.  The LS 245 is getting very hot.  It is an octal bus trancever that connects 74166 to the databus, based on it's inputs from the HAL and the MMU.  The 74166 is also getting very hot and it is controlled by the MMU and the IOU.  The ROMs and the CPU are getting hot because t

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