CuriousMarc | HP 9895A Part 2: Epic Controller Board Repair (and a transparent chip surprise) @CuriousMarc | Uploaded 5 months ago | Updated 2 days ago
We restore more HP 9895A dual 8" diskette HP-IB drives, but these will be way more challenging. We'll need a full on logic analyzer assisted repair to debug a really, really nasty fault. It's a long video, but don't miss the intermission where Master Ken inspects a transparent silicon-on-sapphire chip!
Many thanks to HP enthusiast Craig Ruff for the ROM dump and disassembly.
8" Floppy Playlist: youtube.com/playlist?list=PL-_93BVApb59tOBmcSGTdc79zuEgp6MxF&si=FWBA4AhHjoQ964gh
HP 9825 Playlist: youtube.com/playlist?list=PL-_93BVApb58Hy846J52DT8FeF9USYJUn&si=ubr1GO7EtGn5h8Iy
Ken's Silicon-on-Sapphire chip blog post: http://www.righto.com/2023/12/HP-silicon-on-sapphire-phi-chip.html
Stuff that supports the channel:
- Amazon links for the tools I use in the lab: curiousmarc.com/amazon-links
- Channel merch on Fourthwall: curiousmarc-shop.fourthwall.com
- Legacy channel merch on Teespring (I don't have everything transferred to Fourthwall yet): teespring.com/stores/curiousmarcs-store
- Support us on Patreon: patreon.com/curiousmarc
"Elevator Music" Credit: Crinoline Dreams by Kevin MacLeod
Our lovely sponsors
- PCBWay: fast turn PCBs, pcbway.com
- Electro-Rent: electrorent.com
- Keysight: test instruments: keysight.com
- Samtec: connectors: samtec.com
- R&D Microwaves: rdmicrowaves.com
Get more technical info on the companion site: curiousmarc.com
Contact info: youtube.com/curiousmarc/about
We restore more HP 9895A dual 8" diskette HP-IB drives, but these will be way more challenging. We'll need a full on logic analyzer assisted repair to debug a really, really nasty fault. It's a long video, but don't miss the intermission where Master Ken inspects a transparent silicon-on-sapphire chip!
Many thanks to HP enthusiast Craig Ruff for the ROM dump and disassembly.
8" Floppy Playlist: youtube.com/playlist?list=PL-_93BVApb59tOBmcSGTdc79zuEgp6MxF&si=FWBA4AhHjoQ964gh
HP 9825 Playlist: youtube.com/playlist?list=PL-_93BVApb58Hy846J52DT8FeF9USYJUn&si=ubr1GO7EtGn5h8Iy
Ken's Silicon-on-Sapphire chip blog post: http://www.righto.com/2023/12/HP-silicon-on-sapphire-phi-chip.html
Stuff that supports the channel:
- Amazon links for the tools I use in the lab: curiousmarc.com/amazon-links
- Channel merch on Fourthwall: curiousmarc-shop.fourthwall.com
- Legacy channel merch on Teespring (I don't have everything transferred to Fourthwall yet): teespring.com/stores/curiousmarcs-store
- Support us on Patreon: patreon.com/curiousmarc
"Elevator Music" Credit: Crinoline Dreams by Kevin MacLeod
Our lovely sponsors
- PCBWay: fast turn PCBs, pcbway.com
- Electro-Rent: electrorent.com
- Keysight: test instruments: keysight.com
- Samtec: connectors: samtec.com
- R&D Microwaves: rdmicrowaves.com
Get more technical info on the companion site: curiousmarc.com
Contact info: youtube.com/curiousmarc/about