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hp28s need repair ?. Autotest fails
02-26-2024, 05:41 PM (This post was last modified: 02-26-2024 05:48 PM by tlfrance.)
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tlfrance Offline
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RE: hp28s need repair ?. Autotest fails
Hello,
I've repaired my 28S . I've changed the RAM 32KO chip for a new one on ebay for 7.20€

The original chip is M5M5256BFP 15L (150ns) from Mitsubishi. I've changed for a Nec D43256BGU-70LL (70ns but compatible 150ns) .

[Image: pcb.jpg]
https://ibb.co/VjkBwkJ

Autotest is pass (OK-28S), and all is working well (many lines in stack, program etc..).

Very happy.. Smile
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RE: hp28s need repair ?. Autotest fails - tlfrance - 02-26-2024 05:41 PM



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