Introduced on April 3, 1986, the IBM PC Convertible was IBM’s first laptop computer and was also the first IBM computer to utilize the increasingly common 3.5 inch floppy disk drive. Like modern laptops, it featured power management and the ability to run from batteries.

Weighing in at 13 pounds (5,8 kg), the PC Convertible was based on the Intel 80c88 CPU (a CMOS version of the Intel 8088) running at 4.77 MHz, 256K of RAM (expandable to 512K and later 640K) and featured dual 720K 3.5″ floppy drives, a monochrome CGA-compatible LCD screen and a proprietary snap-on expansion system.

The PC Convertible was priced at $2,000 for a standard configuration. An internal modem could be added for an additional $450. Snap-on expansion adapters could be added , such as a serial/parallel adapter for $195 and CRT display adapter (640 X 200) for $350.

All of these adapters “convert” the Convertible into a more useful machine, but with all of them installed, the system grows an extra 7 inches in length and the weight increases from 12 pounds to 20 pounds, making it rather long and unwieldy.

Introduced into a marketplace that included faster Intel 80286 CPU-based portable computers, many that sold for approximately half the PC Convertible’s $2,000 price tag and others that featured hard drives, the computer sold very poorly. In reviews the PC Convertible’s screen, keyboard and proprietary expansion system were also widely criticized.

Still, with its power management, battery power pack and folding design, the PC Convertible helping establish many of the important features for portable computing that exist today.

Specifications

• Introduced in April 1986
• $2000 with 256K RAM
• RAM expandable to 512K originally, and later 640k
• Intel 80C88 CPU (CMOS version of Intel’s 8088)
• Monochrome LCD display, CGA resolution, able to add external monitor
• IBM PC-DOS with custom icon-oriented shell interface
• Dual 720K 3.5″ floppy drives
• Proprietary snap-on extension in rear for various expansion modules and snap-on peripherals

References

• oldcomputers.net/ibm5140.html
• en.wikipedia.org/wiki/IBM_Convertible
• www.seasip.info/VintagePC/5140.html

One of the most unique computers in the MuMoH collection is the Amstrad PPC 640. The Portable PC with 640 KB of memory was introduced in the Fall of 1987 together with its little brother, a portable PC with 512 KB of memory, aptly named the Amstrad PPC 512. These IBM PC compatibles featured a full keyboard including number pad and a built in 9 inch LCD display that was located on the far left of the computer. But while other portable computers of the day sold for thousands of dollars, the Amstrad PPC 640 and PPC 512 were highly affordable, starting at less than $700.

Here’s an excerpt from an October 1987 news article in the British publication Computer Business Review covering the debut of these computers:

AMSTRAD VAPORISES LAP TOP PRICE UMBRELLA WITH UKP400 PPC

29th October 1987 | From Issue Number: 799

Amstrad Plc will change the economics of owning an MS-DOS portable in January when its PPC range, unveiled in London yesterday, becomes available. There will be four PPC models, with an entry price that at UKP399 plus VAT is roughly half the cheapest competition. For that money, customers get an 8MHz 80C86 processor, 512Kb RAM, one 3.5″ 720K floppy drive, full AT-enhanced keyboard, MDA and CGA compatible graphics, 80 by 25 line 640 by 200 resolution black-on-green Supertwist LCD with six tilt positions, serial and parallel ports, a further port to attach an, as yet unpriced, four-slot expansion box with 20Mb hard disk, 8 hours life from alkaline batteries, MS-DOS 3.3, and a carrying case. For just UKP100 more, they get either an extra 3.5″ drive or 640Kb RAM and a 2,400 bps auto-dial, auto-answer Hayes-compatible internal modem with Softklone Distributing Corp’s Mirror II communications software, and for UKP200 more – UKP599 – they get the extra drive, 640Kb RAM and the modem. As can be seen from the picture, unusually for an LCD, the screen has the aspect ratio of a CRT: it folds back and then the keyboard folds over it to create a long narrow package with the handle at the side. The 17.8″ by 9″ by 4″ PPCs weigh a touch under 12lbs and will be delivered after the Which Computer? Show in mid-January. They will be shown at Comdex in Las Vegas next week. Prices in overseas markets excluding local sales taxes will be similar to those in the UK. After coming a cropper on his estimates for first year sales of the PC1512, Amstrad boss Alan Sugar said he would never again talk about expected volumes but he did admit he hoped to look back in five years time having sold several hundred thousand of the PPCs. He also hinted that Amstrad was considering a portable version of its PCW word processor. The UK unveiling of the PPC is avoid criticism of its products being launched overseas first.

In October 1987, UKP399 was approximately $680 U.S.

The gray PPC 640 and the beige PPC 512 both employed the NEC V30 processor running at 8MHz, one or two 720k 3.5″ floppy drives, a built-in modem, and standard peripheral connectors for serial (RS-232), parallel (Centronics) and video (CGA/MDA). Both computers were powered by ten C-size alkaline batteries when portable, but also came with AC adapters and the ability to power the unit from the car cigarette lighter.

As these were IBM PC compatibles, they used MS-DOS 3.3. Programmed into ROM memory was the Organizer software, a suite of utility applications that included contact mangers, calendar, calculator and modem dialer. The PPC 640 also came with Mirror II, a communications package for use with the built-in modem. The MS-DOS boot disk also included a utility which could be used to switch between the internal display and an external monitor without rebooting.

References

en.wikipedia.org/wiki/PPC_512

www.thepcmuseum.net/details.php?RECORD_KEY(museum)=id&id(museum)=370

www.sinasohn.com/cgi-bin/clascomp/bldhtm.pl?computer=ppc640

www.amstradcg.nl/eppc.html