For traditional analog and CW LMR maintenance, the Bird 43 and 43P remain widely used field wattmeters.

For modern digital LMR systems, the Bird 4480A is Bird’s newer element-free digital wattmeter designed for CW and digitally modulated signals, offering broad 2–1000 MHz coverage, automatic reflected-power/VSWR measurements, and a digital display for faster field troubleshooting.  

Unlike traditional analog wattmeters that can overestimate power on digitally modulated signals, the 4480A accurately measures true average power. This ensures more reliable system calibration, better communication reliability, and compliance with regulatory standards. 

Yes. The 4480A measures forward and reflected power simultaneously and displays VSWR or Return Loss in real time — no manual calculations required.

Yes. The 4480A uses Schottky diodes operating in the square law region, allowing it to provide true average power measurements for both traditional CW signals and modern digitally modulated signals like AM, FM, and other complex formats.

Because when you're working with complex digital signals, small measurement errors can lead to big problems—missed faults, incorrect power levels, or wasted time troubleshooting issues that aren’t really there.

The 4480A delivers ±4% accuracy across its full operating range, including on digitally modulated signals. That means:

• You get reliable, repeatable readings, even in noisy or dynamic RF environments

• You can trust what you’re seeing—no guessing, no second tests

• You stay within spec for power limits, system balance, and performance compliance

In short, accuracy protects your system and your time—and the 4480A is built to give you that confidence without the need for calibration curves, correction factors, or ideal lab conditions.

We recommend recalibration every 12 months to ensure the highest measurement accuracy. This interval aligns with industry best practices for RF power measurement equipment.