68kMLA Classic Interface
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| Click here to select a new forum. | | Daystar Powercache P33 troubles | Posted by: chiptripper on 2024-07-08 21:08:19
I have a dead 50mhz P33 Powercache. It neither powers nor caches.
No obvious damage or corrosion. Tried swapping CPU, FPU, oscillator. Checked all the caps and resistors. I just get a bright, blank screen in an otherwise healthy IIci.
At this point, I wonder if a previous owner plugged it directly into an SE/30 PDS slot. Just a theory. If so, looks like 40a, 40b and 40c would’ve seen 12v or -12v. 40a is GND 40c runs to a 74F573D. Anyone dealt with that scenario with a P33 before? | Posted by: chiptripper on 2024-07-24 12:04:52
I ordered a replacement 74F573D (cost about $1), pulled and replaced. No change.
I’m definitely curious if a SE/30 PDS installation would cause damage beyond the latch chip. But again, it’s really just a hunch. Could be something else unrelated.
So, where to look next? P33 is a challenge to probe. Guess I’ll make an extension cable for the PSU and run the LB outside of the case. | Posted by: JC8080 on 2024-07-24 12:25:59
You can use an ATX extension cable, there are just some unused pins that hang off the end of the connector. | | 1 |
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