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I have a project that requires a dedicated oscilloscope, to "tune" a project, specifically a sawtooth waveform. Is it possible to have such a thing as a scope that once the project is on, there will no need to tune or fiddle around with the scope function (as the users of this project will most likely be idiots, and will not care to learn how to use the scope function).
SCOPE UP!!!!!!!!
- Thread starter Kim Sleep
- Start date
What frequency are we talking about? There are a wide variety of ways to use phones, laptops, etc. as an oscilloscope but they typically can't handle frequency very far above the audible range. It's trickier if you need a true, dedicated oscilloscope. In that case I'd suggest putting it behind a board or something to disable user "input".
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A tablet is another option. You can get a Fire tablet for under $100 and install an oscilloscope app on it.
Something like this might typically be done using a suitable microcontroller to drive a graphic LCD (or similar) display. There are lots of pretty cheap modules available that have the functionality you (seem to be) describing, but you need to find one that you can either hack and hard code the desired settings, or that you can configure as part of your power up process.
Can they be preprogrammed or can the settings be set by an MCU?
It sounds like a key requirement is that when a person powers up the system, that they do not have to (and, in fact, have no way to) adjust the scope settings.
If you only have to tune frequency, a frequency counter would do the job.
I think there are tons of MCU based projects out there to get an idea from. Sawtooth require a Schmitt Trigger to use as a TIM clock.
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What is it that need to be tuned? The frequency? Amplitude? Offset?
Why is an oscilloscope required for this? Can alternatives be considered?
Yes sir!
sure, I just cannot think of an alternative
can it just work to display what I want, without fiddling??
Yes, that is correct, no fiddling!!
Since this is well within the audio range, I'd look for a phone/tablet/laptop and software solution. If the budget is important, an expired phone can likely be obtained for next to nothing. An iPad or aging laptop is not much more.
To protect things, do not attach the "grounds" of any devices connected to wall power. That can create an unintended current path and damage one or the other devices. It's no issue for a device operating on its battery, only for wall-connected devices.
I'd also recommend capacitive coupling between your signal source and the "oscilloscope". This will prevent DC current flow but will easily pass your 1kHz signal. This coupling applies to a direct connection into an audio-in port. If you use the microphone and pass the signal audibly, you don't need to worry about it.
Before you said it was a sawtooth. Now you are saying a triangle wave. Which is it?
Again, what is it about the waveform that is important? What is the user going to do with the information they see displayed on the scope face? What is it they are trying to achieve?
As usual, we are being asked to offer solutions to a problem that isn't spelled out.
What is the goal? What is the underlying problem that needs to be addressed?
If the user is going to turn a knob in order to set the frequency to a desired value, then seeing a waveform on a display is probably less desirable then seeing a numerical display of the waveforms frequency. The same for other parameters.
No, most of the time you will need to page through menus etc. to get to the setup you need.
The only foolproof way I can see is to get an open source scope module and hack the code to have it just power-up in the exact mode you want.
Or... as others have pointed out, if you can detail exactly what the REAL problem you are trying to solve is, I am sure there is a MUCH simpler/better/cheaper way to address it.
You state: "users of this project will most likely be idiots"
Ask yourself this question: when is the last time you saw a product with an oscilloscope screen to be used by idiots?
I see a major contradiction here
This ESP32-based project could do what you want (assuming it is of sufficient bandwidth), it may need some software tweaks but it is open source.
Most of the cheap bench oscilloscopes (and some portable ones) I worked have a setting that defines how the oscilloscope is configured when powered up: either from default settings or from how it was configured the last time. Also, some of them have options to lock the keyboard.
Naturally, these oscilloscopes are more expensive than a regular cheap kit such as the DSO138, but a portable such as Zoyi ZT702S or 703S are better priced.
We don't know the details that surround this request but, if it is for a simple display for machine operators or the general public, then the portable option could be more easily embedded in a panel.
Naturally, these oscilloscopes are more expensive than a regular cheap kit such as the DSO138, but a portable such as Zoyi ZT702S or 703S are better priced.
We don't know the details that surround this request but, if it is for a simple display for machine operators or the general public, then the portable option could be more easily embedded in a panel.
