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I recently purchased a used analog Tektronix 453 and I want to capture some single shot transients. I also want to "save" the waveform so I can more easily measure things like peak to peak voltage of the transient. I know you can review saved one-shots in modern oscilloscopes but do analog scopes also support this useful feature?

In the manual, I see that single-shot trigger allows for "photographs" of the triggered waveform. However, after my trigger is activated, the waveform disappears. Changing the time/div or horizontal display doesn't show that any waveform is "saved". I am not sure how you would be able to photograph any transients since your window for taking the photograph would only be as long as your one-shot duration.

I would imagine analog memory to be much more expensive than digital memory but I don't understand the usefulness of one-shot captures without the possibility for later analysis.

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    \$\begingroup\$ In that old-school era, folks did photograph the CRT face, often with a polaroid camera/film. These special cameras clamped to the CRT face bezel and had a shroud that provided a dark environment. Yes, some analog high-end oscilloscopes had analog waveform storage - not your Tek 453. \$\endgroup\$ – glen_geek Aug 20 '20 at 15:46
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    \$\begingroup\$ I believe there used to be camera attachment with shutter trigger for photographing the screen, analog scopes with delay line memory did exist example 2465 series scope had DMM overlays (voltage and time cursors) and some rudimentary trace memory. \$\endgroup\$ – crasic Aug 20 '20 at 15:48
  • \$\begingroup\$ The 2465 is 20 years newer than the 453. \$\endgroup\$ – pericynthion Aug 20 '20 at 16:53
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Camera. The word you are looking for is camera.

Tektronix made one for your scope, but good luck finding one these days. You'll need even more luck (and maybe deep pockets) to get the needed instant film for the camera.

This is the camera Tektronix made for your scope:

enter image description here


Shameless plug

As an alternative, I can suggest the software I wrote to do similar tasks with my equally old Telequipment D43.

You'll need a web camera and an adapter for your scope.

Mine looks like this:

enter image description here

The software can capture one shot events, despite not having any electrical connection to the scope.

This image is a one shot capturing contact bounce on a switch:

enter image description here

You'll notice there are cursors on screen, and readouts below - you can make measurements like on a (somewhat) modern digital storage oscilloscope with the software.

You can also digitize the trace. That only works for a single trace. I use it to export data to other programs (like Baudline for spectrum analysis.)

I have a bunch of blog posts on it, and there's a Wiki for it on GitHub.

The software runs on Linux and Windows, and probably on Apple (if some one could try it out.)


As a final alternative, you could try the Fads to Obsessions webcam oscilloscope software.

It looks like this:

enter image description here

I tried to use it, but couldn't get it to run under Linux. (It is admittedly a Windows only program, but the Wine Windows emulator can some times work wonders - except this time.)

It's just as well that it didn't work. My software runs real time - the Fads to Obsessions software seems to only take snapshots on demand.

It has a different set of features than my software. Maybe it will suit you better.

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    \$\begingroup\$ Neat! Thanks for sharing and this does breathe life into this old equipment. \$\endgroup\$ – crasic Aug 20 '20 at 15:54

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