TRS-80 Model 100

Launched in 1983, the TRS-80 Model 100 is widely considered the first truly practical portable computer. Built by Kyocera and branded by Tandy/Radio Shack, it featured an 8-line LCD screen, built-in modem, word processor, BASIC interpreter, and a legendary ROM-based OS co-developed by Bill Gates himself. With instant-on capability and battery-powered operation, it became a favorite of field journalists and mobile professionals long before laptops became mainstream.

Notable Features

• Included software: Text editor, Address Book, Scheduler, Terminal, Microsoft BASIC

• Built-in 300 baud modem (optional), ideal for early dial-in systems

• Fully static CMOS hardware — instant-on boot and battery-saving operation

• Used by journalists like Steve Ciarcia and Peter Jennings, even into the 1990s

• Featured ROM software partly written by Bill Gates and Microsoft Japan

---

Historical Significance

• One of the earliest “notebook-style” computers with practical field use

• Huge success in journalism, public safety, education, and inventory tracking

• Set the template for ROM-based laptops like the Epson HX-20 and NEC PC-8201

• Helped prove the viability of solid-state portable computing before hard drives were small or cheap enough to carry

---

Collector's Notes

• Rarity: Moderate – units are common but clean, boxed examples are collectible

• Desirability: Very high among portable computing enthusiasts and journalists

• Common Issues:

  • LCD screen fading or dead rows

  • Corroded battery contacts

  • Internal battery (for RAM retention) failing

• Display Tips: Best shown running built-in apps, a terminal session, or custom BASIC scripts — and it still works great with a serial cable!

Specifications

Technical Information
Name	TRS-80 Model 100
Manufacturer	Tandy
Launched	Tuesday, March 1, 1983
Discontinued	1986
Launch Price	$799 USD (8KB RAM)
Country	Japan / USA
CPU	ntel 80C85 @ 2.4 MHz
Units Sold	6 million across all branded variants
Power	4 × AA batteries (20+ hours runtime), or 6V DC adapter
Operating System	ROM-based text environment with menu-driven apps
Expansion	RS-232 serial, parallel printer port, optional modem, ROM cartridge
Storage	Internal RAM; cassette interface; optional ROM pack; bar code wand
Keyboard	Full-travel 56-key QWERTY keyboard with dedicated function keys
Sound	Simple internal beeper
Graphics	Limited pixel-based drawing via BASIC commands
Display	8-line × 40-character monochrome LCD (240×64 pixels total)
ROM	32KB ROM with built-in apps and Microsoft BASIC
RAM	8KB standard (up to 32KB in later versions)