Review: Tektronix RSA306 spectrum analyser (part 1)

December 03, 2014 // By Kenneth Wyatt
The spectrum analyser has always been a vital tool for the EMC engineer. Until the last few years, these instruments have been rather large and heavy desktop instruments, weighing up to 30 kg, or more.

With the breakthroughs in components used for wireless technology, the size and weight of these instruments has decreased dramatically. This is good news for product designers whose workbenches may already be cluttered with other test instruments or for those like myself who work a lot in the field or travel a lot.

A few other manufacturers have pioneered the concept of PC-controlled spectrum analysers and Tektronix has recently entered the fray with its RSA306, which has dramatically raised the bar in terms of performance and measurement capability. The RSA306 is a well-built rubber-covered unit that is about the size that will slip into the jacket pocket of your suit (30 x 190 x 127 mm). It would also fit easily into a briefcase along with a 15-inch PC laptop. It is designed to meet MIL-STD-28800 Class 2 environmental, shock and vibration for use in harsh environments. The RSA306 is powered solely through the USB 3.0 port. The frequency range is 9 kHz to 6.2 GHz and can measure from +20 to -160 dBm (at minimum resolution bandwidth of 100 Hz). The unit can capture fast transient pulses with its 40 MHz real-time IF bandwidth. There are also external 10 MHz reference and trigger/sync SMA inputs, so you can sync to line frequencies, for example. The measurement input is an N connector with protective rubber cap. With all this, Tektronix has been able to keep the cost down to just €2,810 for the basic unit. Included in this price are a safety/installation manual, USB 3.0 cable and USB flash drive containing the documentation files, user manual, drivers and SignalVu-PC software.

Figure 1 The Tektronix RSA306 is a small rugged package that can easily fit into a briefcase, along with your laptop.

One reason for the low cost is that much of the functionality lies in the SignalVu-PC RF analysis software. The software includes 17 standard spectrum and signal analysis measurements, with several optional application-specific options available (€757, each). These options include mapping, modulation analysis, standards support (such as APCO P25 and WLAN), pulse measurements and frequency settling. The real time (DPX mode) can detect transient or intermittent signals as short as 100 µsec, which would aid in interference hunting. The software can also capture streaming and audio demodulation for long-term surveillance monitoring. Because the personality of the instrument lies within the software, upgrades and adding optional measurement capabilities are easy.

Figure 2 The RSA306 connected to a Mac laptop running Windows 8. The harmonics from an Arduino controller are being measured. The regular spectrum and waterfall are displayed.

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