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The Compaq Portable is probably the best choice for an 8088-class retro computer because its portability makes it easy to store away. In making this model, Compaq was the first to successfully replicate the BIOS necessary to tie the IBM PC's off-the-shelf hardware with the licensable MS-DOS—thus setting the stage for multiple manufacturers making computers for a common platform that could all use the same software and add-on hardware. (Instead of multiple manufacturers making multiple platforms—the situation before 1983.)

This particular machine was already clean inside and out, and only used in non-smoking environments. There are minor scuffs and scrapes on the case, and some age marks on some decals. There is a small crack at one panel corner and a broken internal chassis attachment tab, both now repaired with epoxy (see pictures).

This refurbished unit fixes these failures common to this model:

Non-working power supply replaced with 120 watt AC adapter + 150 watt Pico PSU + ATX to AT adapter (for providing legacy -5 volt rail), all sitting on a plexiglass sheet the same size as the original power supply. The original connectors and standoffs have been repurposed here, epoxied to the plexiglass and soldered to the outputs of the Pico PSU and AT adapter. All soldered connections are robust and a safe distance from each other. The AC adapter is grounded to the chassis through the original grounding pin.
All foam and foil key pads replaced with better foam and foil. All 83 keys now work with consistent response and firmer feel.
10µF-15v tantalum capacitors replaced with 10µF-25v electrolytic ones for 12v/-12v rails on motherboard and floppy board, and 12v rail on video board (no -12v on this board).

With these upgrades this machine should work reliably for many years to come. Also the HardCard* has been replaced with a TexElec SD card to ISA adapter. One of the original 5.25" floppy drives is replaced with a 3.5", 1.44M Sony MFP920, which is recognized as a 720K drive. It sits in a 3D-printed plastic bezel, and is wired to the chassis for grounding. This drive can format cheaper and easier to find (just see here) 1.44M floppies to 720K for use in a modern computer equipped with a regular or USB floppy drive.

Other features:

BIOS upgraded to version G in the mid eighties: enables hard drive booting and reading/writing 720K, 3.5" floppies.
The XTIDE BIOS extension allows booting either the 3.5" or 5.25" floppy drives through A/B key press.
512 MB SD card (partition and filesystem aligned to erase blocks) with MS-DOS 5.0 installed plus office programs and games.

AST Six-Pack Plus board: increases memory to 640K, adds serial port and battery-powered clock. The ASTCLOCK.COM utility is patched for Y2K.
Cleaned and lubricated Magnetic Peripherals 9409, 360K, 5.25" floppy drive.
Original Compaq display board, version K. Motherboard default settings display monochrome text to the internal monitor only, graphics and composite TV are enabled with CTRL+ALT+< key combination. Most games will do this automatically.
Original Compaq floppy/parallel port board.

All components are in good working order using the Checkit diagnostic utility.

* The HardCard will be included, low-level formatted for three heads of the original four, because of erratic errors on one side of the two platters, the remaining three have been thoroughly tested are in good condition. This reduces the capacity from 20 to 15MB.

Shipping: I ship within two business days after payment. International buyers should be familiar with their country's import laws and tariffs and expect their application on this item. I can combine shipments for multiple items (see my other listings) and can arrange for local pick-up if you live near Detroit, Michigan

Return Policy: Notify me within 30 days of receiving the item if there's a problem. After receiving the item back from you in the same condition it was sent, I'll fully refund your purchase price and initial shipping.