Casio SF-4000 Digital Diary Value Guide

The Casio SF-4000 Digital Diary is a landmark of late 1980s personal computing, representing the transition from paper planners to early mobile technology. Launched in 1988, this Japanese-made device was a pioneer in the PDA market, offering a then-impressive 32KB of memory for storing schedules and telephone directories.

What Is Casio SF-4000 Digital Diary Worth?

The typical price range for Casio SF-4000 Digital Diary is $18 - $20 based on recent sales. However, values can vary depending on the item's condition, rarity, and other factors such as:

• Functional condition of the 32KB internal memory and the responsiveness of the membrane keys.
• LCD screen clarity, specifically the absence of 'screen rot' or leaking liquid crystals common in vintage electronics.
• Completeness of the set, including the original retail box, manual, and battery compartment cover.
• Physical state of the plastic clamshell hinge, which is prone to cracking or loosening over time.

How to Identify Casio SF-4000 Digital Diary?

• Verify the 'SF-4000' model number printed clearly on the top right of the clamshell casing.
• Check for the dual-input layout featuring a full QWERTY keyboard alongside a dedicated numeric keypad.
• Confirm the 'Made in Japan' marking on the rear identification plate, typical of the 1988-1990 production era.
• Ensure the presence of the monochrome LCD screen which displays multiple lines of text for memos and calendars.

History of Casio SF-4000 Digital Diary

Launched in 1988, the SF-4000 was a pioneer in the personal digital assistant market. It offered 32KB of memory to store telephone directories, schedules, and memos, bridging the gap between paper planners and the modern smartphone.