68kMLA Classic Interface

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6100/60 PSU swap
Posted by: petteri on 2026-09-30 12:41:54 I got a 6100/60 with Macintosh Color Display, AEK II, mouse and original manuals. It also came with boxed games 'Spectre VR' and 'Indiana Jones and the Fate of Atlantis' disk version. The computer is clean inside and has almost intact plastics. But the DCF 803 PSU is dead, produces clicking sound and low voltages. I might recap it but I also happen to have a small PSU (Seventeam ST-220FUB-05E) from a 1U Watchguard firewall appliance. It is much smaller than the original PSU and wiring it looks straightforward. I checked this https://pappp.net/?p=65693 but looks like the PSU connector has +5V, GND, +12V and -12V. So no soft start from keyboard on 6100?
Posted by: nzmacuser on 2026-10-01 08:41:27 That's right the Macintosh 6100 doesn't have a soft start feature. It uses the same case design as the Centris 610. I suppose that 1U would work, provided it's PCB fits inside the DCF803 enclosure without creating a fire hazard You could reuse some of the DCF803's existing wiring for the IEC connector, switch etc. Note, the 1U PSU is rated at +5v@8A, where as the original is rated at +5V@11.6A. This probably won't matter unless you max out the 6100 with addon cards. There is another thread on here where a guy used a Meanwell RPT-160B PSU. It may be easier to just recap the original PSU, if the existing caps show obvious signs of leakage and degradation.
Posted by: petteri on 2026-10-02 12:44:12 I think the replacement PSU is powerful enough and it should fit inside the 6100 case nicely. The idea is to save the original PSU for later repairs. I was planning to unpin the ATX connector but I couldn't get any out. So I cut and crimped necessary wires. I didn't find a 10 pin connector so I sawed down 4x2 and 5x2 connectors. The hard drive power cable(s) and some kind of power switch needs to be done but I got the computer booting and reading from the disk drive.
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