Help Luis play back waveforms
A reader recently asked for help on how to capture a waveform with an oscilloscope and play it back on a waveform generator. Having neither of his instruments in my office, I put this question to you.Luis uses a Fluke 105B ScopeMeter, which he describes as “Simple and rock solid.” He uses the optical RS-232 interface and the FlukeView software to capture waveforms and remotely control the ScopeMeter.
Recently, Luis acquired an arbitrary waveform generator, a Model 4070 from B&K Precision. “My dream was to set up a waveform recorder and play back the waveform using this two instruments,” he said. He tried saving waveforms in csv format with the ScopeMeter, hoping to then use the waveform generator to play back the waveforms. That’s where he ran into difficulty.
Luis noted that B&K Precision software that Luis can use to “draw waveforms and save them in many formats. He thought that importing the .csv waveforms from the Fluke and playing them back on the 4070 would be easy. But, Luis reports that “The waveform is usually out of range and not near the original. I have tried many ways and all the formats shared by both instruments.” Luis asked B&K Precision about the problem, but he was told that B&K didn’t write the software.
Luis would like help on how to get his oscillosocpe and waveform generator to work properly with a common file format. He would consider purchasing another oscilloscope that would work better at providing him with data files that he can use with the B&K 4070 so he can record waveforms and play them back for testing. He needs a bandwidth of at least 60 MHz.
Both the Fluke 105B and the B&K 4070 are discontinued.
Post your comments and suggestions below.
Lily commented:
Good piotns all around. Truly appreciated.
Donna Mitchell commented:
SynaptiCAD makes a waveform translator software, WaveFormer Pro, that can write out files to the Tektronix's AWGs and read in files from Tektronix and Agilent oscopes. The software is a timing diagram editor, so you can also create the waveforms directly in the software by drawing or simulating them. It supports over 30 different waveform formats, so it should work with about any equipment that you eventually choose.
Johnnie commented:
Agilent has just published a 4-page Measurement Tip titled, “Waveform Capture and Playback Made Easy”. This application document, which directly addresses the issue of this blog topic, describes how you can capture a waveform on a scope, save it in a .CSV format on a USB memory device, and then directly import and replay the waveform on an Agilent arbitrary waveform generator. Although this doesn’t solve the Fluke scope and B&K arb issue, it does show how Agilent has addressed the issue without requiring a PC connection with software. This document can be downloaded at cp.literature.agilent.com/litweb/pdf/5990-8167EN.pdf .
Bill G. commented:
Capture playback is one of my favorite T&M applications. My first job out of college was working for HP, HP was uniquely qualified to capture events that occur “one time” and then able to replay them all day long. The combination of unique analog technology combined with state of the art workstations provided great insights. One particular day a fellow engineer turned to me and said, “wow, we are the only people in the world to ever see this”. Turn the clock forward and now you can do it all day with an oscilloscope, function generator and a thumb drive. Following is a link to the youtube video “33500 Series Function Generator Oscilloscope Capture and Transfer”, about a 1 minute long: youtu.be/mXdkwAxa_Ik
Alan commented:
The update rate of the BK4070 is 40MS/s so is below the 60MS/s spec mentioned.
Another issue might be the tiny memory of the Fluke scope - only 256 samples. Also its real time sampling rate is only 25MS/s. I suspect the scope is limiting what you can do more than the AWG.
Given the above and the fact he is already connecting via a PC to transfer data it might make sense to swap to using a PC oscilloscope with a built in AWG.
The PicoScope 5000 and 6000 series seem to meet the spec as the AWGs are faster than the BK4070 and the scope faster than the Fluke.
eager_b commented:
You may have thought of this already but make sure that the sample rate of the waveform you’re trying to generate matches the sample rate of the acquired waveform ...and... matches a sample rate that your signal source is capable of mimicking. Slight differences in the time bases of the two instruments can yield unsatisfactory results.
w2aew commented:
To my knowledge, the BK 4070 was limited to about 20MHz. He may want to look at the Tektronix AFG3000 series of Arbitrary Function Generators. There are models that will cover 60MHz easily. Tek offers free software (called ArbExpress) that makes it easy to import waveforms from Tek scopes and send them to the AFG.
antiquus commented:
If, as you say, the problem is "usually out of range", the solution is a matter of scaling and offsetting the values. Import the CSV to Excel, do the math, and export a new CSV file.
