If you continue browsing the site you consent to our cookie use.Unique widescreen display, friendly interface and easy-to-use operations.Innovative solutions for automated measurement and test, measurement data acquisition and transmission.He conducts seminars on embedded systems and helps companies with their embedded challenges, and works as an expert witness on embedded issues.
Saelig, their US distributor, loaned me one for evaluation, and the bottom line is that this baby packs a ton of capability into one small and inexpensive package. If you can live without the TG (tracking generator) option the DSA815 is 1295. For instance, you could feed the TG into a filter and the filters output to the SAs input to display the filters frequency response. Everyone knows that an oscilloscope displays voltage on the vertical axis, and time on the horizontal. An SA shows amplitude on the vertical and frequency on the horizontal. The following picture shows the Rigol displaying the FM radio band. The center frequency is 100 MHz with a span of 20 MHz (that is, the SA is sweeping from 90 to 110 MHz), RBW and VBW (more on these later) of 3 KHz. The marker is barely visible as a 1 towards the left side of the screen. WBJC, at 91.5 MHz in the photo, comes in at -75 dBm, or around 50 picowatts. When in the noise I found them just about impossible to recognize. In contrast, the SA is just like a superhet radio a local oscillator sweeps from a user-selected low frequency up to a desired high frequency, with phenomenal gain since a mixer stage isolates just the frequency being swept at any time. If youre doing any sort of wireless work an SA is an essential bit of test equipment. So setting this to a big number means a perfect sine wave, which should show as a infinitely-narrow spike in a perfect world, will be broad and mushy. A narrow RBW will display that sine wave as a spike, or nearly so. VBW is video bandwidth, a smoothing filter applied to the displayed data. Obviously youd want to set RBW as narrow as possible and VBW just where the data is reasonably noise-free. Pretty slick k in the above formula is an SA-dependent constant. I found that with a 1 MHz span, and RBW VBW 1 KHz, the sweep took 3.3 seconds, compared with one second for the much more expensive Advantest. I measured it at -105 dBm, or around 0.05 picowatt. Thats pretty good, though the big test equipment vendors have much more sensitive gear, for much more money. And there are a ton of other features, like the ability to do n sweeps and stop, where n is any number from 0 to 9999. And theres a passfail mode as found on some scopes: if a waveform falls outside some boundaries a fail signal is generated. Lots of measurements are included like total power, power on adjacent channels, carrier to noise ratio, power of each harmonic, THD and VSWR. The manual, which is generally of barely adequate quality, is very good in the section on the measurements.
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