Advantest R5373K Microwave frequency counter

The Advantest R5373K is a microwave frequency counter engineered for precise measurement across a broad frequency spectrum from 10 mHz to 27 GHz. Built for telecommunications, research, and development applications, it delivers 1 Hz resolution in 1 second using digital TRAHET technique and achieves up to 0.1 mHz maximum resolution with selectable decade steps from 0.1 Hz to 10 MHz. The instrument features dual input channels

Channel 1 spans 10 Hz to 550 MHz with 25 mV sensitivity and 50 Ω impedance, while Channel 2 begins at 500 MHz.

Accuracy is specified as ±1 count ± time base accuracy.

Technical Specifications

• Frequency Range: 10 mHz to 27 GHz


• Channel 1 Input: 10 Hz to 550 MHz; Channel 2 Input: 500 MHz minimum


• Resolution: Selectable 0.1 Hz to 10 MHz; maximum 0.1 mHz resolution


• Channel 1 Sensitivity: 25 mV


• Channel 1 Impedance: 50 Ω


• Input Coupling: AC


• Input Attenuation: x1, x20


• Maximum Input Voltage (Channel 1): 5 V (–10 V to +10 V with 20 dB attenuation)


• Pulse Specifications: 0.5 µs minimum pulse width; 10 Hz to 5 MHz PRF


• Time Base Output: 10 MHz, 1 Vp-p (min.), approx. 50 Ω impedance


• External Standard Input: 1–10 Vp-p at 1, 2, 2.5, 5, or 10 MHz; approx. 500 Ω input impedance


• Accuracy: ±1 count ± time base accuracy

Key Features

• Digital comparator with keyed upper/lower limits


• Maximum/minimum value hold and deviation measurement (max – min)


• Standard deviation, averaging, and PPM calculation


• Offset, drift, and scaling display functions


• Sum and difference display for automatic dual-input measurement


• Harmonic frequency and arithmetic operations


• D-A analog output (–4.995 V to +4.995 V ± 20 mV @ 23°C ± 5°C; 100 Ω max impedance)


• Totalize function for DC to 10 MHz band (0 to 9,999,999,999 count capacity)


• FM tolerance: ±125 MHz or more (≥1.4 GHz manual); ±25 MHz (500 MHz to 1.4 GHz manual); 10 MHz p-p worst case (automatic)

Typical Applications

• Microwave signal frequency validation in RF systems


• Pulse and PRF characterization in radar and communications


• Frequency stability analysis and time base verification


• Multi-parameter signal analysis using calculation and hold functions

Compatibility & Integration External frequency standard inputs accept 1, 2, 2.5, 5, and 10 MHz references. Time base output enables synchronization with external instruments via BNC connectors.