MMU address line resistors changed to 68ohms. Why?

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Atarian Computing
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MMU address line resistors changed to 68ohms. Why?

Post by Atarian Computing »

I started working on a 520STM, without floppy. Everything seems to work but I noticed that someone had replaced the original 33ohm resistors on the address lines to 68ohms. The memory is the standard 512K that I plan to upgrade to 1MB via piggyback method.

Question is, why would one need to replace these resistors and what implications are there for having 68ohms?
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exxos
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Re: MMU address line resistors changed to 68ohms. Why?

Post by exxos »

Probably someone didn't know what they were doing and put wrong ones back in.
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Atarian Computing
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Re: MMU address line resistors changed to 68ohms. Why?

Post by Atarian Computing »

exxos wrote: Sat May 26, 2018 8:45 pm Probably someone didn't know what they were doing and put wrong ones back in.
Wonder why they would do that... You can't see from the picture but they actually snipped the original resistors off and soldered these on the stumps. I guess I'll just put 33 ohm ones back in.
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