Extech 380400 Resistance Decade Box is a precision electrical test tool designed for use in electronics design, troubleshooting, calibration, and laboratory environments. It provides a convenient way to substitute precise resistance values into a circuit without needing to swap individual components, making it ideal for prototyping, testing, and setting up or verifying measurement and control systems.

Key Features

Wide resistance range: Adjustable from 1 Ω up to 11,111,110 Ω in 1 Ω increments, allowing fine-tuned resistance selection for many applications.

Seven decade ranges: Slide switches provide easy setting of resistance values across seven decades.

Rugged construction: Durable housing built for frequent use in lab, shop, or field settings.

Three binding posts: Provide isolated connection points for easy integration with test leads, banana plugs, or bare wires.

Groundable case: The box’s chassis can be grounded separately to suit specific test setups.

High accuracy: Around ±1% resistance tolerance, suitable for general-purpose engineering and calibration checks.

Low internal resistance: Approximately 0.3 Ω internal resistance helps ensure accurate substitution results.

Typical Applications

Substituting precise resistance values during circuit design and prototyping

Calibrating and verifying electronic instruments

Testing and troubleshooting sensors, resistive components, and control circuits

Educational labs and training environments

General Specifications

Resistance Range: 1 Ω to 11,111,110 Ω (1 Ω steps)

Accuracy: ±1%

Internal Resistance: ~0.3 Ω

Power Rating: 0.3 W resistors

Connections: 3 binding posts

Dimensions: ~5.8″ × 4.6″ × 1.3″ (147 × 117 × 33 mm)

Weight: ~0.69 lb (312 g)