Broad workload coverage
The Fluke 9640A and 9640A-LPN Reference Generators can help you simplify the RF calibration process, by helping you to calibrate a broad range of RF test equipment:
- Spectrum analyzers
- Modulation meters and analyzers
- RF power meters and sensors
- Measurement receivers
- Frequency counters
- And more
High signal purity and low phase noise
The 9640A generates a pure sinusoidal signal with extremely low harmonics, spurious and residual modulations. This ensures that level accuracy will be maintained when you make measurements with wideband or narrow band detectors, or when the 9640A is intercomparing peak and RMS sensing instruments. You will avoid differences between the wideband/ narrow band and peak/RMS sensors, without requiring additional filters.
The importance of low phase noise on signal sources is often overlooked. The phase noise profiles of the Fluke 9640A are designed around the spectrum analyzer workload; the 9640A suits the vast majority, while the 9640A-LPN is capable of verifying the most demanding spectrum analyzers. Use the low phase noise specification to measure spectrum analyzer phase noise, close-in response and residual FM. Previous systems typically used two low noise signal generators to cover close-in and far-out measurements, or simply didn’t cover the far out (>100 kHz offset). Now you can handle both with a single 9640A-LPN.
Level accuracy and broad frequency coverage in one instrument
Calibration often involves use of several popular signal sources spanning a wide range of frequencies. Some of the most popular signal sources are now obsolete. You would normally need three signal generators, plus a power meter and sensors, to cover the entire frequency range of today’s workload with the required accuracy.
Whether your RF calibration workload has a frequency bandwidth of 4 GHz or 40 GHz, the Fluke 9640A handles the broadest portion of the RF calibration procedure in a cost effective solution.
Precision leveling head minimizes mismatch errors
A rugged, precision leveling head delivers the 9640A signals directly to the unit under test, minimizing losses, noise and mismatch errors, and maintaining the integrity of low-level signals. The head maintains signal precision and noise immunity throughout a 154 dB dynamic range, down to the very lowest levels at -130 dBm.
The leveling head reduces lead changes from 25 to just 5 during a typical calibration, extending unattended times in an automated system and reducing connector wear.
By integrating signal leveling and attenuation within the leveling head, the 9640A eliminates the need for separate, step attenuators, simplifying automation and reducing cost of ownership. It also eliminates the need to use an external power meter and sensors to characterize the output at different frequency and levels.
VSWR and mismatch errors are often the dominant source of measurement uncertainty in RF applications. Connecting the leveling head output directly to the load minimizes transmission line length and VSWR degradation due to cabling, allowing the full potential of its accuracy specifications to be realized at the load across the entire frequency range.
The standard 9640A and 9640A-LPN models are supplied with a 50 Ohm leveling head and the models have additional 75 Ohm leveling head. Mainframe and heads are calibrated together as a system.
Internal AM and FM modulation
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.
External frequency reference input/output
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
HP 3335A and optional HP 8662A/8663A command emulation
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).
Another long-discontinued instrument is the HP 8662A or HP 8663A low phase noise synthesizer. The 9640A-LPN is designed to match or exceed all HP 8662A/8663A performance and functionality within the calibration system. HP 8662 and HP 8663 GPIB command emulation is available as a “try before you buy” optional license key enabling on the 9640A-LPN.
Either way, you can greatly simplify integration of the 9640A into an existing automated system.