Fluke 7220A – Universal Frequency Counter

The Fluke 7220A is a nine-digit universal frequency counter delivering high-precision measurements up to 1300 MHz across dual input channels. Channel A covers 10 Hz to 125 MHz at 1 MΩ impedance with switchable and continuously variable attenuation, while Channel B handles 100 MHz to 1300 MHz at 50 Ω impedance with sensitivity as low as 5 mV rms. The instrument supports burst mode triggering and features a fully EMI-shielded enclosure meeting MIL-STD-461 requirements for operation in demanding RF environments.

Housed in Fluke's lightweight Portable Test Instrument case with stack-and-latch design, the 7220A integrates into GPIB systems via optional IEEE-488 connectivity through the Fluke 1120A Translator. An optional 1000-times resolution multiplier maintains measurement speed while extending resolution capabilities.

Technical Specifications

• Frequency Range

Channel A: 10 Hz to 125 MHz; Channel B: 100 MHz to 1300 MHz

• Input Impedance

Channel A: 1 MΩ (AC coupled); Channel B: 50 Ω

• Sensitivity

Channel A: 10 mV rms (10 Hz–50 MHz), 15 mV rms (50–100 MHz), 35 mV rms (100–125 MHz); Channel B: 5 mV rms (100–500 MHz), 10 mV rms (500–1000 MHz), 20 mV rms (1000–1300 MHz)

Maximum Input (Channel B): 5 Vrms

VSWR (Channel B): 2.5:1

Display: 9-digit

Time Base: 1 ppm TCXO (option 7220A-111)

Resolution Multiplier: 1000x option (7220A-351)

Key Features

• Dual-channel architecture optimized for low- and high-frequency applications


• Channel A front-end includes X1/X10 switchable attenuation and continuously variable 1x to 10x wideband attenuator


• Burst mode measurement capability


• Fully EMI-shielded enclosure per MIL-STD-461


• Integral stainless steel RF shielding


• Portable configuration: 12 × 10 × 10 inches, 5 lbs

Compatibility & Integration Optional IEEE-488 connectivity via Fluke 1120A Translator enables integration into automated test systems. Standard package includes Counter Digital Interface Unit and Y7203 2 ft ribbon cable with personality card.