9640A - Fluke RF Reference Source

Fluke 9640A 4 GHz RF Reference Source with 9640A-50 50Ω leveling head and HP 3335A GPIB command emulation.

Product Overview:
The Fluke 9640A RF Reference Source has been designed to simplify RF calibration while improving productivity and lowering cost. The Fluke 9640A Reference Source is the first RF calibrator to combine level precision, dynamic range and frequency capability in a single instrument. It can be used to calibrate a broad range of RF test equipment including spectrum analyzers, modulation meters and analyzers, RF power meters and sensors, measurement receivers, frequency counters and attenuators. With built-in signal leveling and attenuation, the Fluke 9640A provides the frequency range and precision required to replace many commonly used RF calibration devices including level generators, RF signal generators, power meters and sensors, step attenuators and function generators.

The Fluke 9640A is supported by a range of common RF workload procedures within the Fluke MET/CAL? Plus Calibration Measurement Software, allowing quick automation of the calibration process while simplifying the documentation requirements for quality standards and tracking assets.

Designed to handle the broadest portion of the RF calibration workload, the Fluke 9640A provides frequency coverage from 10 Hz up to 4 GHz with a best level accuracy of 0.05 dB. It outputs a pure sinusoidal signal with low harmonic and spurious content, helping eliminate differences between the wideband/narrowband and peak/RMS sensors without requiring additional external filters.

The Fluke 9640A also features integrated signal leveling and attenuation within its rugged precision leveling head, eliminating the need to use separate, often difficult-to-automate step attenuators. The leveling head delivers signals directly to the unit under test (UTT), maintaining signal precision and noise immunity throughout a +24 dBm to -130 dBm dynamic range to minimize losses, noise, mismatch errors and to maintain the calibrated integrity of the signal. The Fluke 9640A comes with a 50 ohm leveling head and has an option to add a 75 ohm head, which extends the instrument's capability to calibrate workload with 50 and 75 ohm inputs, a unique characteristic in modern signal sources.

Designed to simplify calibration laboratory applications, the Fluke 9640A features dedicated function keys, context-sensitive softkeys and a bright color display. Users may set a level or frequency step size and deviate the output to match specified target values while the Fluke 9640A displays the calculated UUT error for calibration certificate documentation.

The 9640A Reference Source’s internal modulation capability makes it suitable for applications that require precision modulation to be applied to the output signal, such as modulation analyzer calibration and spectrum analyzer sweep time testing using AM methods. You don’t need additional function generators as a low frequency modulation source – the 9640A delivers it all. Frequency modulation is available at rates up to 300 kHz for applications such as modulation analyzer testing. Amplitude modulation is available at depths of up to 99 % and rates up to 200 kHz.

RF applications often require a frequency sweep. The 9640A’s sweep functions simplify the application of manual legacy spectrum analyzer frequency response testing, as well as filter response.

Selectable external frequency reference input is available on the rear panel of the 9640A. The input allows you to lock the frequency output to an external reference, such as the Fluke 910R Rubidium Standard, for applications where high clock accuracy or use of a common reference frequency is important. The frequency reference output allows a UUT to be frequency locked to the 9640A internal reference clock. This configuration is often required to reduce frequency offset errors that may occur between the reference source and the UUT

The HP 3335A Synthesizer/Level Generator, discontinued long ago, has been an essential component in many users' RF calibration systems. Until now, there have been few alternatives to match its level and attenuation accuracy. The 9640A RF Reference Source matches or exceeds HP 3335A performance, and has a GPIB command interpreter capable of emulating the HP 3335A in a calibration system (including 75 Ohm applications).