Compaq Contura Aero 4/33C

Compaq released Aero 4/25 and 4/33 small notebook computers in 1994. They were one of the first computers of small factor, they had even no floppy disk drive nor CD drive - everything was external. This gave the machine possibility to be ultra-portable. Compaq experimented with pointing devices by using trackball in different places - in this unit is is on the right part of casing while buttons ae located on its side, in other models they moved trackball to the lid, right below LCD, while buttons were on the other side - you had to grab it and move the ball with thumb, pressing buttons with index and middle finger.
The computer had to be energy-efficient, so it has a small, low-power 486SX processor running at 33MHz. On board, there is 4MB of RAM expandable by modules. Models were equipped with drives from 84MB to 250MB. Aero notebooks were supplied with MS-DOS and Windows 3.x, floppy drive was PCMCIA-based. Simulatnaously a LapLink-like solution was pre-installed to transfer data by COM port. Although video card had 512kB, only 256kB was accessible allowing 640x480 to be displayed.   
Because of their small size these computers were quite expensive and never got true popularity. However there are still some fan-clubs of these small computers.

Manufacturer Compaq

Origin USA
Year of unit 1994
Year of introduction 1994
Type Laptop, PC
CPU Intel 486SX, 33MHz
expandable with modules
Floppy Disk External only (PCMCIA)
Hard Disk 250MB IDE
Other media None
Graphics and display: LCD display, 640x480 in 16 colors
Sound: PC Speaker
Keyboard and pointing device: Small PC keyboard

Trackball with 2 buttons located on side.

OS: MS-DOS, Windows 3.x

Power supply:

1 - GND
2 - 17.5V DC, 2.5A
(17V works too)

I/O: Serial port, parallel port, PCMCIA, dock/expansion connector.
Possible upgrades:  - RAM Expansion
 - External FDD
Additional peripherals:  none

My unit has been bought in flea market and its origins are unknown. Its hard disk contains Windows 95, installation, a few DOS games and nothing more, especially that disk is severely damaged by bad sectors. I don't have also a floppy drive for it so I can't even replace the hard disk as BIOS Setup partition needs to be restored from floppy disks as in Compaq Presario CDS510. For what I've found, it was bought in Poland and used until 2002-2003 when it fell while operating.

The computer needs PCMCIA floppy disk drive. You may encounter problem while installing operating system from floppies which loads own PCMCIA drivers - floppy may disappear in the middle of preparing to install. The solution is to use hard disk to store installation files or skip PCMCIA drivers loading during install. Some traces point to the hint that this computer can boot from RS232 too, but they are too vague to be used.

Servcie manual and FAQ
Setup and diags disk (SP 2054)
BIOS/DOS/Win drivers/tools pack (SPs 0993, 1992, 1454, 1743, 1125, 2158, 1630, 2517, 0891, 0801, 1585)


Contents: Hinge fix and disassembly Links  

Hinge fix

2019 June: Got two additional units, one with broken hinge, or clutch. This is a significant problem in these units - hinges were made with Zinc-Aluminum alloy, which breaks easily. To fix it, the mcahine must be disassembled.

To disassemble the computer you have to remove bottom screws and rear screws. Then, top cover can be unlatched. Do it slowly proceeding from removed battery compartment. The top part then can be removed.
To remove keyboard, remove upper and lower screws, open it, unlatch ribbons, remove it. Now you have access to LCD ribbon which you can unlatch and you can access BIOS battery too.
Now the lid can be removed: First, a right hinge (which usually breaks) and then slide it off the right hinge's tube. Do not loose the smaller tube, it has a notch to fit well.
To disassemble the lid, the screws are under round stickers. After removing them, unlatch the LCD bezel. Now you have access to LCD and right hinge.
Placing washers between screws and the right hinge's tab prevents the problem for some time. Especially in the hole closer to the hinge.
If the hinge is broken, avoid opening/closing the lid as it may damage the lid's threaded holes! ...and the only cure will be to glue them back with two-compound cement.

As these hinges are unobtainable now, I decided to make my own part of the clutch. First, removing the broken part, leaving only the hinge and shaft. To do this, it is needed to hold the broken part in vice, put a nail or screw in the hole and gently hit it until the hinge falls off.
Then, I cut an L-shaped piece of metal from an old metal plate from keyboard and machined it with file to dimensions. This old plate had square holes for keys, so it was easier to cut using existing holes. The shorter part of "L" is a bit wider and longer, so it was possible to grab it into vice and just use the hammer to make a round profile, with internal diameter like the shaft protruding from the hinge.
The next step was to push the hinge's shaft into it by squeezing it in vice. Generally the harder it goes, the better.

Finally, drilled holes in a longer part of "L" and put it in case as it originally was. Although this is ready to be installed, there are two things I recommend:
1. Find a longer screw for the part closer to the keyboard (it breaks there). Because my re-make was thicker and because point 2.
2. Use a washer between this screw's head and the metal part.
There is literally no sign outside that the hinge is re-made.

Links - Webpage with information about programs, manuals for download and SoftPaqs listed. - Little Aero page - - Aero stuff - Links, very good FAQ, diagrams, photos. - Compaq Aero Land - Information and (mostly outdated) links. - Base unit connector pinout (Local mirror)