We want to measure two voltages at 0.01 sec intervals over 20 minutes. The signals are not repetitive, so we’ll need to download the results and do some averaging. These requirements require large memory for slow speed, compared to many applications. What are good (100 MHz, for other applications) instruments to accomplish this at a reasonable price? Would a Rigol DHO814 oscilloscope be a good choice? B&K Precision 2194? Siglent SDS 814X-HD?
Greetings,
Most oscilloscopes aren’t really made to accommodate the sort of longer-term measurements in question; 100Hz sampling for 20 minutes is really more of a “data logging” or “data acquisition” task, for which various products in this family are more adapted.
Much of what one pays for there is the convenience of a device and software package that minimizes setup efforts. If one doesn’t mind doing a bit of the work oneself, there are devices such as this that can be used to get the job done for all of ~$20 or so.
There are also middle-ground devices such as Digilent’s Analog Discovery 3 that put some rather capable multi-function I/O on the end of a USB cable and mate it with a flexible software package that takes advantage of the multiple ways that it can be used. While not as convenient, capable, or flexible as purpose-built equipment, a single device that can serve as a o-scope, waveform generator, data logger, logic analyzer, spectrum analyzer, network analyzer, pattern generator, and a few other things all for ~$400 has some appeal.