HP 82901M 5.25in 270K FDD
| This device is in the WorkNeeded:ReplacementParts category because it was flagged as missing information on replacement parts. If it has the original parts listed you may be able to search for replacements using the parametric searches available from parts distributors. If you have or make a list of replacement parts, please feel free to add them by copying the relevant table from EditorsToolbox:Tables | 
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| Preliminary Information | |
|---|---|
| Release Year | 1980 |
| Leak Risk | Low |
| Batteries | None |
| Mounting Technology | Through Hole |
| Capacitor Types | Aluminum Electrolytic, Tantalum, Ceramic |
| Destructive Entry | No |
| Hardware Specifications | |
| Storage | 5.25" DD Floppy Disks @ ~270KiB |
This is a floppy drive for HP systems with an HP-IB interface to allow them to read LIF formatted 5.25" floppy floppy disks. Internally they use standard full height 5.25" internal drives like a Tandon TM100-2A.
Known Issues
Large Aged Caps
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Power Supply Board with two large capacitors
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Right side capacitor is 10,000uF @ 40VDC
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Left side capacitor is 17,000uF @ 20VDC
Causes
- These capacitors will likely not be bad, but may have degraded from disuse. They can short if powered without caution.
Solutions
- Before powering the device, remove caps (which doesn't even require soldering) and Reform them both.
Disassembly Notes
The logic board for the entire unit is attached through the controller board for the right side drive and may have damaged plastic mounting points on the drive. They are not structurally critical to the operation of the device, but do secure the drive control board in place.
Original Parts
Power Supply
82901-60001
| RefDes | Qty | Capacitance | Voltage | Mount | Diameter/Size | Height | Lead Spacing | Temp | Type | Brand | Series |
|---|---|---|---|---|---|---|---|---|---|---|---|
| n/a | 1 | 10000 µF | 40 | Screw Terminal | -40 to 85°C | Aluminum Electrolytic | Sprague | 32DR COMPULYTIC | |||
| n/a | 1 | 17000 µF | 20 | Screw Terminal | -40 to 85°C | Aluminum Electrolytic | Sprague | 32DR COMPULYTIC |
Note: Sprague PSU caps should have a Capacitor Reforming procedure attempted on them before powering or replacement. Suitable substitute parts are difficult and costly to find so unnecessary replacement is higly discouraged.
Related Links
- More general device info: https://wiki.techtangents.net/wiki/HP_82901M_5.25in_270K_FDD
- Documentation and other info: http://www.hpmuseum.net/display_item.php?hw=287