Microwave measurements that call for robust test signal levels often require an external broadband amplifier along with the signal generator. But the new E8257D option 521 Performance Signal Generator (PSG) from Agilent Technologies can deliver better than 1 W (+30 dBm) output power over most of its 20-GHz frequency range without an additional amplifier while achieving outstanding output-power flatness and low output harmonics (Fig. 1).

High-power test signal levels are often required for antenna testing and automatic-test-equipment (ATE) applications. The new PSG can deliver the test-power levels needed without additional amplifiers, couplers, and detectors (and cost). It operates from 10 MHz to 20 GHz without the typical multiple frequency-banded amplifiers needed to boost output signals over such a broad frequency range with the good output impedance match needed to maintain repeatable output level flatness. Even judging by its conservative leveled output-power specification, the signal generator provides more than +24 dBm (0.25 W) output power across most of its frequency range (Fig. 2).

The E8257D option 521 has a typical standing wave ratio (SWR) of 1.6:1 for carriers above 500 MHz, which supports typical power-level accuracy of 0.2 dB at output levels to +26 dBm. Option 521 also delivers low typical harmonics to reduce or eliminate the need for external filtering. The E8257D option 521 includes a user-adjustable, hardware output-power-clamp feature that helps to protect both users and units under test from high-output-power accidents. The power-clamp capability allows a user to set the output-power clamp (maximum output power out of the signal generator at the RF connectoreven in unleveled conditions) between +15 and +33 dBm with 1-dB resolution. The output-power clamp works in either internal or external power-level control configurations. Agilent Technologies, Inc., 5301 Stevens Creek Blvd., Santa Clara, CA 95051; (800) 829- 4444, e-mail: berry_carone@agilent.com, Internet: www.agilent.com.