IET / General Radio 1433-20 Decade Resistor

The IET/General Radio 1433-20 is a precision decade resistor providing stable, highly accurate resistance values from 1 mΩ to 111.11111111 MΩ. Engineered for laboratory and industrial calibration, testing, and circuit design applications, the 1433-20 delivers 0.01% accuracy with six selectable dials and 0.01 Ω/step resolution. Its gold-plated tellurium-copper binding posts, low zero resistance, and excellent frequency characteristics make it suitable for DC through RF measurements.

Technical Specifications

Resistance Range: 1 mΩ to 111.11111111 MΩ

Total Resistance (1433-20): 11.1111 kΩ

Resolution: 0.01 Ω/step

Accuracy: 0.01% (up to 10 MΩ)

Number of Dials: 6

Temperature Coefficient: <10 ppm/°C (values above 100 Ω); 20 ppm/°C (100 Ω and below, room temperature)

Zero Resistance: <0.001 Ω/decade DC; ~0.04 Ω/dial at 1 MHz

Inductance (Lo): 0.1 µH/decade + 0.2 µH

Shunt Capacitance: 15–20 pF/decade (low terminal to shield); 0–20 pF greater when shield tied to switch or zero end

Maximum Current: 8 A per decade (1 mΩ and 10 mΩ decades)

Voltage to Case: Maximum 2000 V

Switch Capacitance: <1 pF

Key Features

Three-terminal configuration: high (H), low (L), and guard/shield (G)

Gold-plated binding posts, 3/4 inch spacing

Shorting link included

Low, stable zero resistance across frequency

Minimal residual reactance

Long-term stability

Typical Applications

Precision impedance measurement and calibration

RF circuit characterization

Bridge and meter calibration

AC and DC resistance standards

Compatibility & Integration Rear outputs and Kelvin connections available as options [-K Option]. Two-terminal or three-terminal operation supported via guard terminal configuration.