View source for HP 82901M 5.25in 270K FDD

{{DeviceAlerts}}
{{InfoboxDevice
|Picture = 
|Release Year = 1980
|Mounting Technology = Through Hole
|Capacitor Types = Aluminum Electrolytic, Tantalum, Ceramic
|Leak Risk = Low
|Batteries = None
|Destructive Entry = No
|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===
<gallery>
File:HP-89201-PSU-CAPS1.jpg|Power Supply Board with two large capacitors
File:HP-89201-PSU-CAPS2.jpg|Right side capacitor is 10,000uF @ 40VDC
File:HP-89201-PSU-CAPS3.jpg|Left side capacitor is 17,000uF @ 20VDC
</gallery>

====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 [[Capacitor Reforming|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''
{| class="wikitable sortable"
|+Capacitor [[Capacitor Specifications|Specifications]] and [[Part Footprints|Footprint]] Information
!RefDes
!Qty
!Capacitance
!Voltage
![https://caps.wiki/wiki/Part_Footprints Mount]
!Diameter/Size
!Height
!Lead Spacing
!Temp
![https://caps.wiki/wiki/Capacitor_Types Type]
!Brand
!Series
|-
|n/a
|1
|10000 µF
|40
|Screw Terminal
|
|
|
| -40 to 85°C
|Aluminum Electrolytic
|[[Capacitor Brands#Sprague|Sprague]]
|[[Capacitor Series#32DR COMPULYTIC|32DR COMPULYTIC]]
|-
|n/a
|1
|17000 µF
|20
|Screw Terminal
|
|
|
| -40 to 85°C
|Aluminum Electrolytic
|[[Capacitor Brands#Sprague|Sprague]]
|[[Capacitor Series#32DR COMPULYTIC|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
==References==
<references />
[[Category:WorkNeeded:General]]
[[Category:WorkNeeded:OriginalParts]]
[[Category:WorkNeeded:ReplacementParts]]
[[Category:Floppy Drive]]