Rescue 1130: 2014 Pickup of an IBM 1130 System and More rescue1130.blogspot.com

Interim method won't work; assembling new PCB

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Attempting to test the discrete transistor method of resolving the 1130 MRAM retriggering

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Ordered new PCB with my original fab to reduce delays

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Revised design and producing a new board for 1130 MRAM project

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Checking out the low ESR cause for the 1130 MRAM ringing

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Oscillation in LD1117 voltage regulator appears to be the root cause

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Same problem with 1130 MRAM in spite of new board

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Beginning testing of new PCB for 1130 MRAM board

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Replacing some chips on 1130MRAM board based on testing

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Finishing new PCB for 1130 MRAM, waiting on memory chip

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Building new version of the PCB for 1130 MRAM

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More work on retriggering issue with 1130MRAM

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1130 MRAM - quick check after removing large buffer capacitors

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1130MRAM smoking gun found

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1130MRAM spurious retrigger - what it can not be then musings

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Output of Schmidt Trigger after a bit more massaging

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Investigations for 1130 MRAM board - ways to block retriggering of the timer chip

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Continued testing of 1130 MRAM board - results of probed points and added power wires

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Continued testing of 1130 MRAM board - more probes added to zoom in on problem area causing retriggering

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Continued testing 1130MRAM board - retrigger problem continues to bedevil me

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