The Macintosh Portable is a portable computer designed, manufactured and sold by Apple Computer, Inc. from September 1989 to October 1991. It is the first battery-powered Macintosh, which garnered significant excitement from critics, but sales to customers were quite low. It featured a fast, sharp, and expensive black and whiteactive matrixLCD screen in a hinged design that covered the keyboard when the machine was not in use. The Portable was one of the early consumer laptops to employ an active matrix panel, and only the most expensive of the initial PowerBook line, the PowerBook 170, used one, due to the high cost. The cursor pointing function was handled by a built-in trackball that could be removed and located on either side of the keyboard. It used expensive SRAM in an effort to maximize battery life and to provide an "instant on" low-power sleep mode. The machine was designed to deliver high performance, at the cost of increased price and weight.
Known issues
Unlike later portable computers from Apple and other manufacturers, the battery is wired in series with AC power supply. There being no possible alternative direct connection to AC supply, a flat battery meant the computer could not be operated. The original power supply had a very low output. Several popular unauthorized workarounds were devised, including using the power supply from the PowerBook 100 Series which provides a higher output. As with automotive batteries, the sealed lead acid cells used in the Portable failed if they were fully discharged. The batteries are no longer manufactured and it is very rare to find an original battery that will hold a charge and allow the computer to start. It is possible to repack the battery with new cells, or use alternative 6 V batteries. There were three lead-acid cells inside the battery; each were manufactured by Gates Energy Products and they were also used in Quantum 1 battery packs for photographic flash use. Despite the dramatic improvement in terms of ergonomics offered by the responsiveness, sharpness, and uniformity of its active matrix panel, one of the drawbacks of the Portable was poor readability in low-light situations. Consequently, in February 1991, Apple introduced a backlit Macintosh Portable. Along with the new screen, Apple changed the SRAM memory to less expensive pseudo-SRAM, which reduced the total RAM expansion to 8 MB and lowered the price. The backlight feature was a welcomed improvement, but it reduced the battery life by about half. An upgrade kit was also offered for the earlier model as well, which plugged into the ROM expansion slot. The Portable was discontinued in October 1991. In addition, at 16 pounds and 4 inches thick, the Portable was a heavy and bulky portable computer. The main contributor to the Portable's weight and bulk was its lead-acid battery.
Drive configurations
There were three drive configurations available for the Macintosh Portable. A Portable could ship with one floppy drive, with two floppy drives or with a hard drive and a floppy drive. The floppy drive in the Macintosh Portable is 1.44 MB. Most Macintosh Portable units came with a hard drive. It was a custom-engineered Conner CP-3045. It holds 40 MB of data, consumes less power compared to most hard drives of its time and it has a proprietary SCSI connector; adapters that allow standard SCSI drives to be used on the Portable exist, but they are expensive.
Legacy
The Macintosh Portable can run Macintosh System 6.0.4 through System 7.5.5. In May 2006, PC World rated the Macintosh Portable as the seventeenth-worst tech product of all time. By contrast, MacUser magazine noted that this machine tended to remain relevant and therefore tended to have a long usage lifespan for those who bought it, reducing its total cost of ownership.