Sinclair ZX81 16K External RAM Module
A modern reimagining of the classic 16K expansion. Housed in a durable 3D-printed shell, this upgrade features an integrated power LED and a dedicated reset switch for improved reliability and ease of use.
 
If you’re looking to push your 1981 powerhouse to its absolute limits, the Sinclair ZX81 16K RAM Pack is the essential upgrade. Moving beyond the internal 1K—which, let's face it, is barely enough for a game of Hangman—this expansion opens up a world of high-resolution graphics and complex BASIC programming.
 
Key Features
Massive Memory Leap: Boosts your total system memory to 16KB, allowing for deep nested loops and large arrays.
Plug-and-Play: No soldering required. It slides onto the edge connector and is immediately recognized by the system upon power-up.
Classic Aesthetic: Housed in a matching black, textured plastic casing that aligns perfectly with the ZX81's "wedge" silhouette.
Unlocks the Library: Required for the vast majority of commercial software and games released for the system, including 3D Monster Maze.
 
​​​​​​​Technical Specifications
Feature
Detail
Capacity
16 Kilobytes (16,384 bytes)
Interface
ZX81/TS1000 Edge Connector
Technology
Dynamic RAM (DRAM)
Power
Drawn directly from the ZX81 mainboard