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Searching for a particular test instrument is the time-consuming bane of many an RF/microwave engineer. Whether it is a high-speed oscilloscope, a spectrum analyzer, or even a “common” voltmeter, the need for an instrument often exceeds its availability. But with the MDO3000 series of mixed-domain oscilloscopes (MDOs) from Tektronix, finding many of those critical test tools will now come down to finding one compact unit.

Each MDO3000 is potentially six instruments in one, with an oscilloscope, spectrum analyzer, logic analyzer, protocol analyzer, arbitrary function generator (AFG), and digital voltmeter (DVM) contained within a single housing. These instruments can cover a lot of ground, since the oscilloscopes are available with two or four analog input channels and bandwidths ranging from 100 MHz to 1 GHz. The spectrum analyzer can reach as high as 3 GHz. A top choice for debugging chores, these units are also well suited for design and manufacturing workbenches.

Tektronix's MDO3000

Tektronix’s portable test laboratories (see photo) are based on the company’s MSO/DPO3000 Mixed Signal Oscilloscope series, starting with a versatile and powerful MSO and new FastAcq functionality. The latter supports capture rates to more than 280,000 waveforms/s and shows captured signals on a bright digital phosphor display screen. Although they are “packaged” as standard instruments, they feature a host of options that allow specifiers to essentially customize each instrument to a particular set of needs.

The oscilloscopes provide two or four analog input channels and 16 (optional) digital input channels. Standard oscilloscope bandwidths include models for 100, 200, 350, 500, and 1000 MHz, and the spectrum analyzer frequency range of any model can be extended to 3 GHz as an option. The oscilloscopes offer more than 125 trigger combinations to help capture the most complex signal anomalies. They also include automated serial and parallel bus analysis, along with an option for automated power measurements. In addition to the 1 GHz range, these instruments offer a generous selection of extras, including nine optional serial protocol analysis packages: I2C, SPI, RS-232, USB 2.0, CAN, LIN, FlexRay, MIL-STD-1553, and audio.

The optional logic analyzers provide 16 digital channels with a main sample rate of 500 MSamples/s (2 ns timing resolution) and 10 Mpoints record length for capturing details on high-speed signals. When even higher resolution timing measurements are required, the MDO3000 employs a parallel high-speed sampling technology (called MagniVu) that samples each digital channel at 8.25 GSamples/s (121.2-ps timing resolution) into a shorter record that is centered on the trigger event. Users can switch back and forth between the full record and the MagniVu record when needed.

With the integrated protocol analyzer, details shown on the oscilloscope screen can be used to decode a bus under analysis. This analyzer makes it possible to trigger on specific packet data and view decoded data with physical layer or event details. The addition of one or more of the nine optional serial analysis software packages mentioned previously enables the measurement power of the protocol analyzer.  

Adding to the integrated instrument list, an integrated AFG capable of output rates to 250 MSamples/s is available as an option. It includes 128 kpoints waveform memory to enable a user to capture and replicate a signal from the oscilloscope. With its capabilities, it can recreate or generate sine waves to 50 MHz and pulsed signals to 25 MHz. A built-in waveform editor and integrated software provide 13 predefined functions, and operators can use the Tektronix ArbExpress PC-based waveform and editing software to further enhance the waveform creativity of the AFG.

Not to be forgotten, the MDO3000 series instruments include a DVM at no charge when the instrument is registered. The DVM provides 4-digit AC RMS, DC, or AC + DC RMS voltage measurements, as well as 5-digit frequency measurements, with results shown in a large display. The MDO3000 instruments also feature low 3.9-pF input capacitance passive voltage probes for reduced circuit loading. When considering the relatively low prices for the MDO3000 series instruments (starting at $3350 USD), packing multiple test functions into one compact box can save a great deal on the total cost of multiple instruments, not to mention the benefit of finding those required test functions when needed

Tektronix, Inc., 14150 SW Karl Braun Dr., P.O. Box 500, Beaverton, OR 97077; (800) 833-9200.

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