The R140B from Copper Mountain Technologies lets you characterize antennas and cables without the need for an additional test cable.

Cables, connectors, antennas, and other RF passive need characterizing for frequency response, insertion loss, and other parameters. With the R140B 1-port VNA from Copper-mountain technologies, you can connect your device under test directly to the instrument’s test port. Because of the R140B’s small size, you often won’t need an additional cable to the DUT, which eliminates the need to calibrate its losses out of the measurement system. You still need to calibrate, but it’s one less thing to account for.

The R140B covers a frequency range of 85 MHz to 14 GHz. That covers everything from commercial FM to cellular and military frequencies. The single-port VNA lets you characterize devices and get S11 parameters — the input port voltage reflection coefficient. Using two R140Bs lets you measure S12 — reverse-voltage —.

The VNA uses a flexible connector assembly that includes four port-connector options: N plug, N receptacle, 3.5 mm plug, 3.5 mm receptacle. Port impedance is 50 Ω.

The unit connects to a host PC through a USB port. A windows app lets you control the instrument, or you can write your own test-automation app using a command set. The R140B software can display four measurements on a single screen. They include SWR, return loss, cable loss, phase, group delay, Smith charts, polar diagrams. You can set the VNA to sweep across a frequency range in 2 to 100,001 points using linear, log and segments frequency sweeps.

You can convert S-parameters into reflection impedance and admittance, inverse S-parameters, and conjugation. You can also perform limit testing to produce a pass/fail result for production-line tests.