A Christmas Tree for your Lab

It seems like holiday decorations come up earlier and earlier every year. You might not have room for a full-blown tree in your lab, but if you have an arbitrary waveform generator and a scope, Tektronix has a way for you to show your spirit electronically.

You can see the video below. Naturally, it features Tektronix gear, but we are pretty sure you could make it work with any arbitrary waveform generator that has at least two channels and a scope with an XY mode.

The key to making this easy isn’t a Tektronix app. It is WebPlotDigitizer, a web page that helps you load data and extract X and Y coordinates from it. This is actually a very useful tool for any sort of data extraction you might need on an image or plotted data, so it is a rather handy thing to have in your toolbox.

Once you have the coordinates, you have to split the X values into one signal and the Y values into the other channel. It is hard to picture it making the shape you defined until you switch to XY mode and there it is.

Of course, not being satisfied, they used a third channel to add some garland, too. We’ve seen plenty of function generators you could press into this kind of service. We even rolled our own.

11 thoughts on “A Christmas Tree for your Lab

  1. Does anyone know of an app/website that would turn vector graphics into a sound file to display on an XY scope?

    It would be easy to just play the file back on your phone on repeat, and clip the scope leads to the headphone cable.

  2. Now a compiler which takes the image and spits out a discrete circuit (for example with transistors, capacitors and resistors) with two outputs…

    Gah. Stop it. Gotta some work on the pan :-(

  3. I never really understood the draw of Oscilloscope graphics.

    Paper is cheap.

    Old TVs are throw/giveaway items.

    So lets make our graphics on what for many of us is the most expensive and versatile tool on the whole workbench cause higher runtime hours = better?

    I remember when the internet was newer and “inexpensive” used scopes were not a thing… (by my own definition of inexpensive) I tried searching the internet for projects to make an oscilloscope adapter for a tv. All I kept finding were adapters to watch tv on a scope. Why would I ever want to do that?!?!

    1. Why do anything? Obviously it’s not being done as a practical pursuit. It’s just an interesting hobby and a challenge. And it’s not going to wear out the ‘scope with “higher runtime hours.” It’s perfectly harmless.

      Plus, you’ll probably learn a thing or two in your quest to get it working right. Especially if you’re building the driving circuitry. That’s the real value of play and experimentation–it’s one thing to use a tool according to the manual, but it’s another to play with it, push your limits, and acquire a more intuitive understanding of how it works. Or you could make your own Vectrex. Or you could scribble on paper, nobody is stopping you.

    2. many many years ago I had such a device to turn a tV in to a scope – it was crap :lol:
      but it did display a single channle waveform on a TV.

      It was a kit available I think from Dick smiths – this was back around 1985 or so…

  4. The process I used was: Import the CSV from WebPlotDigitizer into Excel. Then, cut and paste the column of waveform data points into Notepad and saved as a .txt file. Then, open ArbExpress (see link below) and open the .txt file and select the “Volt format. Then, use File > Save As to save the waveform as a .tfw format. Repeat for the other waveform. I didn’t include these details in the video in the interest of time…
    https://www.tek.com/signal-generator/afg2021-software-0

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.