Editing PowerBook Duo (section)

==={{anchor|Duo Dock}}Duo Dock (M7779) (1992), Duo Dock II (1994), Duo Dock Plus (1995)===
[[File:Duodock.jpg|thumb|right|Duo Dock]]

This was the largest and most expensive dock for the PowerBook Duo, in a form factor common for that period: the Duo Dock (M7779) was first offered by Apple on October 19, 1992,<ref>{{Cite web|title=PowerBook Duo Dock Specs: EveryMac.com|url=https://everymac.com/systems/apple/powerbook_duo/specs/mac_powerbook_duodock.html|access-date=2021-01-06|website=everymac.com}}</ref> and the similar docks presented by Compaq (as the [[Compaq LTE Lite|LTE Lite]] [[Compaq LTE#Docking stations|Desktop Expansion Base]])<ref>[http://www.1000bit.it/ad/bro/compaq/Compaq-LTE-Family.pdf Compaq LTE Family of personal computers] ''1000bit.it'' </ref> and [[IBM]] (as the 3550 Expansion Unit)<ref>{{Cite web|title=Service Manual - IBM Expansion Unit (3550) - Notebook|url=https://www.opweb.de/english/company/IBM/Expansion_Unit_-3550|access-date=2021-01-06|website=www.opweb.de}}</ref> were introduced in the same year. Unlike the smaller docks, or "port replicators" that plugged into the back of laptops, the listed docks pulled the laptop inside the dock's metal and plastic case via an internal sliding mechanism (similar to that of a VHS recorder). The Duo Dock turned the PowerBook Duo into a full-size, AC-powered, fully functional desktop computer with all the standard ports.<ref name="SS1">{{cite web |url=http://www.sleuthsayers.org/2011/10/apple-today.html |title=An Apple Today |last=Lundin |first=Leigh |work=Technology |publisher=SleuthSayers.org |location=[[Orlando, Florida]] |date=October 9, 2011}}</ref> Like a desktop computer, the dock could physically support a heavy, high-resolution CRT display on top. The Duo Dock included a [[Floppy disk|floppy drive]] on the side, two [[NuBus]] expansion slots, an optional [[floating-point unit]] (FPU), level 2 cache, a slot for more VRAM to enable more colors at higher resolutions, and space for a second hard drive.<ref name="SS1" />

The original Duo Dock was replaced by the Duo Dock II on May 16, 1994, which added [[Apple Attachment Unit Interface|AAUI]] networking and compatibility with the newer color-screen PowerBook Duos. A replacement lid was offered to allow use of the thicker color Duos with the original Duo Dock. 

The Dock II was followed by the Duo Dock Plus on May 15, 1995, which was identical to the Duo Dock II, but lacked the FPU and level 2 cache—which were not compatible with the [[Motorola 68040|68LC040]]-processor Duo 280 and PowerPC-processor Duo 2300c. While the laptop's LCD display obviously could not be opened when inside the dock, additional NuBus video cards could be installed to drive up to three monitors.

Aging Duo Docks are known to have problems with the failing of the capacitors which drive the docking mechanism. This is colloquially known as 'The Duo Dock Tick of Death'.<ref>{{Cite web|title=The Duo Dock Tick of Death: lowendmac.com|url=https://lowendmac.com/2016/the-duo-dock-tick-of-death/|access-date=2021-05-16|website=lowendmac.com|date=September 3, 2016}}</ref>