438A

The Keysight (formerly Agilent/HP) 438A is a dual-channel power meter designed specifically for Automatic Test Equipment (ATE) systems. Its compact dual-channel design saves rack space while enabling straightforward and accurate measurements of power level ratios and differences from two separate sensors, making it well-suited for multi-port measurements and determining gain compression. The meter is compatible with the industry-standard 8480 series of power sensors and includes GPIB capability as a standard feature.

Automated Test Equipment Power Measurement RF and Microwave

Specifications

General

Parameter	Value
Interfaces	GPIB
Display	Liquid Crystal Display (LCD)

Physical

Parameter	Value
Power Supply	100 / 120 / 220 / 240 Vac (+5% to -10%), 48-66 Hz or 360-440 Hz, 65 VA max
Operating Temperature	0 to 55
Dimensions (W×H×D)	213 x 89 x 418
Weight	5.9

Measurement Characteristics

Parameter	Value
Number of Channels	2
Compatible Sensors	Keysight/Agilent/HP 8480 Series
Power Range	-70 to +44 dBm (sensor dependent)
Dynamic Range	50 dB
Measurement Modes	A, B, A-B, B-A, A/B, B/A

Power Reference Oscillator

Parameter	Value
Reference Frequency	50 MHz
Reference Power Level	1.00 mW (0.0 dBm)
Connector Type	Type-N (female)

Interfaces and Connectivity

Parameter	Value
Remote Control Interface	GPIB (Standard); MATE CIIL (Option 700)

Performance

Parameter	Value
Instrumentation Accuracy	±0.5% (±0.02 dB)
Zero Set	±0.5% of full scale on most sensitive range
Reference Oscillator Accuracy	±1.2% worst case for 1 year
Channel Math Functions	A/B, B/A, A-B, B-A
Offset Range	-99.99 to +99.99 dB

Inputs & Outputs

Parameter	Value
Recorder Outputs	0 to 1 Vdc into ≥1 kΩ (one BNC per channel on rear panel)
Rear Panel Sensor Inputs	Available with Option 002

Environmental

Parameter	Value
Storage Temperature	-40 °C to +75 °C

Technology

RF/Microwave

Applications

ATE Systems / Power Measurement