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Test-and-measurement instruments are essential, but often expensive, tools that aid in the design and development of electronic products. For most electronic device, component, and system manufacturers, acquisition of building-block instruments such as oscilloscopes, spectrum analyzers, and power supplies can represent major investments—and thus put sizable dents—in a company’s operating expenses.
Addressing those concerns, Rohde & Schwarz, a leading supplier of high-end electronic test instruments, introduced a line of “value” instruments, including three digital oscilloscopes, an RF/microwave spectrum analyzer, and a precision power supply, that provide top performance levels without charging top dollar. They are designed and built with cost-effective quality in mind, yet manufactured in the same European facilities as the firm’s top-of-the-line electronic instruments, bringing even more electronic measurement power for the dollar than ever before.
The oscilloscope models are more like three different series of instruments, with many different options and upgrades. It’s possible to start with a basic set of measurement functions and capabilities, and then via license keys, unlock much more extended performance later.
For example, the “entry-level” oscilloscope, the R&SRTB2000 is available with two or four channels and 3-dB measurement bandwidths of 70, 100, 200, and 300 MHz (Fig. 1). Real-time sampling extends to 1.25 Gsamples/s in normal measurement mode and to 2.5 Gsamples/s when channels are interleaved. The memory per channel is 10 Msamples in normal mode and 20 Msamples for interleaved measurements. As much as 160-Msample segmented memory enables more than 13,000 recordings when long-term measurements are required.
1. The R&SRTB2000 oscilloscopes come with two or four channels and 3-dB bandwidths of 70, 100, 200, and 300 MHz.
These “budget” digital oscilloscopes leverage a high-resolution, 10-b analog-to-digital converter (ADC) at the 2.5-Gsample/s sampling rate (with as much as 16-b vertical resolution in high-resolution decimation mode). Test results are shown on a bright, 10.1-in. capacitive touchscreen display with 12 horizontal divisions and 180- × 800-pixel resolution. The display screen also provides straightforward access to the operating menus.
The R&SRTB2000 oscilloscopes provide 1-mV/div vertical resolution at full bandwidth to go with an input sensitivity range of 1 mV/div to 5 V/div and 10%/90% rise times of 5 ns or better. The instruments feature a history mode for analysis of saved, earlier measurements, among many other handy, automatic measurement functions.
In addition to being digital oscilloscopes, the R&SRTB2000 value instruments include several measurement functions that can be activated via license keys, including a 4-bit pattern generator and a signal waveform generator with 14-bit resolution and 250-Msample/s sample rate.
The waveform generator is capable of an amplitude range of 20 mV to 5 V into high-impedance loads and 10 mV to 2.5 V into 50-Ω loads. It can create sine waves from 0.1 Hz to 25 MHz and pulses from 0.1 Hz to 10 MHz. The oscilloscopes are supported by a wide range of available probes and accessories, including lower- and high-voltage single-ended passive probes, ac/dc current probes, and active differential probes.
When more bandwidth and measurement power is needed, the R&SRTM3000 digital oscilloscopes are also available with two and four channels, but with 3-dB bandwidths of 100, 200, 350, 500, and 1000 MHz (Fig. 2). They provide 40-Msample memory depth on each channel with maximum sampling rate to 5 Gsamples/s, also showing results on a 10.1-in. capacitive touchscreen with 1280- × 800-pixel display resolution and 12 horizontal divisions.
2. The R&SRTM3000 oscilloscopes (left) include models with two and four channels and bandwidths of 100, 200, 350, 500, and 1000 MHz. The R&SRTA4000 instruments (right) are digital oscilloscopes with bandwidths to 1000 MHz that also incorporate a logic analyzer, spectrum analyzer, protocol analyzer, arbitrary waveform generator, pattern generator, counter, and digital voltmeter.
The R&SRTM3000 is even closer to being a complete measurement system than the R&SRTB2000, with available additions of a logic analyzer, protocol analyzer, waveform and pattern generators, and digital voltmeter. In addition, there are dedicated operating modes for frequency analysis, mask tests, and long data acquisitions for serial protocol signal analysis.
Finally, for the value oscilloscopes, the R&SRTA4000 instruments are also built around a 10.1-in. capacitive touchscreen display with 12 horizontal divisions and 180- × 800-pixel resolution, but provide the highest sensitivity at 500 µV/div. Models/upgrades are available with bandwidths of 200, 350, 500, and 1000 MHz and standard sampling rates of 2.5 Gsamples/s per channel and 5.0 Gsamples/s interleaved with up to 1,000 Msamples of memory. It offers low noise performance, even at 1 mV/div and full bandwidth.
In terms of packing measurement power into one package, these are eight instruments in one, with oscilloscope, logic analyzer, spectrum analyzer, protocol analyzer, arbitrary waveform generator, pattern generator, counter, and digital voltmeter. The built-in protocol analyzer, for example, can be used to analyze and debug serial buses with long-duration signals.
Spectrum Analysis
For measurements in the frequency domain, the R&SFPC1500 spectrum analyzer (Fig. 3) has a starting frequency range of 5 kHz to 1 GHz with license key upgrades that activate measurement capabilities extending to 2 and 3 GHz as needed. These analyzers handle input signal levels as high as 1 W (+30 dBm) and feature a noise floor of −165 dBm when using a preamplifier.
3. The R&SFPC1500 spectrum analyzers are available from 5 kHz to 1, 2, or 3 GHz, with vector network analyzer and test signal sources included.
With resolution bandwidth as fine as 1 Hz, the analyzer can resolve the smallest signal details, which are shown on a high-resolution 10.1-in. WXGA display screen. As with the other value instruments, the R&SFPC1500 spectrum analyzer is not “simply” a spectrum analyzer, but rather include two additional high-frequency instruments—a vector network analyzer and tracking generator—both of which are available for frequency coverage from 5 kHz to 1, 2, or 3 GHz.
When laboratory power is needed, the R&SHMP power supplies provide two, three, or four electrically equivalent channels of low-ripple voltage to 32 V in a single instrument. Models come with two or three channels and as much as 188 W total output power or three or four channels and as much as 384 W total output power. The supplies use remote sensing to eliminate voltage drops on load leads, and incorporate galvanically isolated, floating output ports with overload and short-circuit protection. When teamed with any of the other value instruments, they provide part of a cost-effective measurement solution that’s as useful in the laboratory as the production line. P&A: $1,370 (USD) and up (R&SRTB2000).
